6.6.2. The working cross-sectional area of ​​the samples is determined from the measurement results as the arithmetic mean of the areas of two opposite faces.

6.6.3. The compressive strength of the solution is calculated as the arithmetic mean of the test results of three samples.

6.6.4. The test results are entered in the journal in the form in accordance with Appendix 2.

7. DETERMINATION OF THE AVERAGE DENSITY OF THE SOLUTION

7.1. The density of the solution is determined by testing cubes with an edge of 70.7 mm, made from a mortar mixture of the working composition, or plates with a size of 50X50 mm taken from the seams of structures. The thickness of the plates should correspond to the thickness of the seam.

In production control, the density of solutions is determined by testing samples intended to determine the strength of a solution.

7.2. Samples are made and tested in batches. The batch shall consist of three samples.

7.3. Equipment, materials

7.3.1. To carry out the test, apply:

technical scales in accordance with GOST 24104-88;

vernier caliper in accordance with GOST 166-89;

steel rulers in accordance with GOST 427-75;

desiccator in accordance with GOST 25336-82;

anhydrous calcium chloride according to GOST 450-77 or sulfuric acid with a density of 1.84 g / cm 3 according to GOST 2184-77;

paraffin in accordance with GOST 23683-89.

7.4. Test preparation

7.4.1. The density of the solution is determined by testing samples in the state natural moisture or normalized moisture condition: dry, air-dry, normal, water-saturated.

7.4.2. When determining the density of a solution in a state of natural moisture, the samples are tested immediately after they are taken or stored in a vapor-tight package or sealed container, the volume of which exceeds the volume of the samples placed in it by no more than 2 times.

7.4.3. The density of the solution at the normalized moisture state is determined by testing the samples of the solution having the normalized moisture content or arbitrary moisture content with the subsequent recalculation of the results obtained to the normalized moisture content according to the formula (7).

7.4.4. When determining the density of a solution in a dry state, the samples are dried to constant weight in accordance with the requirements of clause 8.5.1.

7.4.5. When determining the density of a solution in an air-dry state, before testing, the samples are kept for at least 28 days in a room at a temperature of (25 ± 10) ° С and a relative humidity of (50 ± 20)%.

7.4.6. When determining the density of a solution under normal humidity conditions, the samples are stored for 28 days in a normal hardening chamber, desiccator or other sealed container at a relative humidity of at least 95% and a temperature of (20 ± 2) ° C.

7.4.7. When determining the density of a solution in a water-saturated state, the samples are saturated with water in accordance with the requirements of clause 9.4.

7.5. Testing

7.5.1. The volume of the samples is calculated by their geometric dimensions. The dimensions of the samples are determined with a caliper with an error of no more than 0.1 mm.

7.5.2. The mass of the samples is determined by weighing with an error of not more than 0.1%.

7.6. Processing of results

7.6.1. The density of the sample solution r w is calculated with an error of up to 1 kg / m 3 according to the formula

where T - sample weight, g;

V — sample volume, cm 3.

7.6.2. The density of the solution of a series of samples is calculated as the arithmetic mean of the test results of all samples of the series.

Note. If the determination of the density and strength of the solution is carried out by testing the same samples, then the samples rejected when determining the strength of the solution are not taken into account when determining its density.

7.6.3. The density of the solution at a normalized moisture state r n, kg / m 3, is calculated by the formula

(7)

where r w is the density of the solution at humidity W m, kgf / m 3;

W n ¾ normalized moisture content of the solution,%;

W m ¾ the moisture content of the solution at the time of testing, determined in accordance with Sec. eight.

7.6.4. The test results must be entered in the log in the form in accordance with Appendix 2.

8. DETERMINATION OF THE MOISTURE OF THE SOLUTION

8.1. The moisture content of the solution is determined by testing samples or samples obtained by crushing samples after testing them for strength or extracted from finished products or designs.

8.2. The largest size of the crushed pieces of mortar should be no more than 5 mm.

8.3. Samples of samples are crushed and weighed immediately after sampling and stored in a vapor-tight package or sealed container, the volume of which does not exceed the volume of the samples placed in it by more than two times.

8.4. Apparatus and materials

8.4.1. The following are used for testing:

laboratory scales in accordance with GOST 24104-88;

drying cabinet in accordance with OST 16.0.801.397-87;

desiccator in accordance with GOST 25336-82;

baking sheets;

calcium chloride in accordance with GOST 450-77.

8.5. Testing

8.5.1. The prepared samples or samples are weighed and dried to constant weight at a temperature of (105 ± 5) ° С.

Plaster solutions are dried at a temperature of 45–55 ° C.

The mass at which the results of two successive weighings differ by no more than 0.1% is considered constant. In this case, the time between weighings should be at least 4 hours.

8.5.2. Before re-weighing, the samples are cooled in a desiccator with anhydrous calcium chloride or together with drying cabinet to room temperature.

8.5.3. Weighing is carried out with an error of up to 0.1 g.

8.6. Processing of results

8.6.1. The moisture content of the solution by weight W m as a percentage is calculated with an error of up to 0.1% according to the formula

(8)

where T v — mass of the solution sample before drying, g;

T With — mass of the solution sample after drying, g.

8.6.2. The moisture content of the solution by volume W o as a percentage, calculated with an error of up to 0.1% according to the formula

where r about - the density of the dry solution, determined according to clause 7.6.1;

8.6.3. The moisture content of a solution of a series of samples is determined as the arithmetic mean of the results of determining the moisture content of individual solution samples.

8.6.4. The test results should be recorded in a logbook, which indicates:

place and time of sampling;

moisture state of the solution;

mortar age and test date;

sample labeling;

the moisture content of the solution of samples (samples) and series by weight;

moisture content of the solution of samples (samples) and series by volume.

9. DETERMINATION OF WATER ABSORPTION OF SOLUTION

9.1. The water absorption of the solution is determined by testing the samples. The sizes and number of samples are taken in accordance with clause 7.1.

9.2. Apparatus and materials

9.2.1. The following are used for testing:

laboratory scales in accordance with GOST 24104-88;

drying cabinet in accordance with OST 16.0.801.397-87;

container for saturation of samples with water;

wire brush or abrasive stone.

9.3. Test preparation

9.3.1. The surface of the samples is cleaned of dust, dirt and traces of grease using a wire brush or an abrasive stone.

9.3.2. Samples are tested in a state of natural moisture or dried to constant weight.

9.4. Testing

9.4.1. The samples are placed in a container filled with water so that the water level in the container is about 50 mm higher than the upper level of the laid samples.

The samples are placed on spacers so that the height of the sample is minimized.

The water temperature in the container should be (20 ± 2) ° С.

9.4.2. The samples are weighed every 24 hours of water absorption on a conventional or hydrostatic balance with an error of not more than 0.1%.

When weighing on a conventional balance, samples taken out of water are preliminarily wiped with a wrung out damp cloth.

9.4.3. The test is carried out until the results of two successive weighings differ by no more than 0.1%.

9.4.4. Samples tested in the state of natural moisture, after the end of the water saturation process, are dried to constant weight according to clause 8.5.1.

9.5. Processing of results

9.5.1. Water absorption of a solution of a separate sample by weight W m as a percentage is determined with an error of up to 0.1% according to the formula

where T With — the mass of the dried sample, g;

m c is the mass of the water-saturated sample, g.

9.5.2. Water absorption of a solution of a separate sample by volume W o as a percentage is determined with an error of up to 0.1% by the formula

( 11)

where r about - the density of the dry solution, kg / m 3;

r in - the density of water, taken equal to 1 g / cm 3.

9.5.3. The water absorption of a solution of a series of samples is determined as the arithmetic mean of the test results of individual samples in a series.

9.5.4. In the journal in which the test results are recorded, the following columns should be provided:

labeling of samples;

mortar age and test date;

water absorption of the sample solution;

water absorption of a solution of a batch of a sample.

10. DETERMINATION OF THE FROST RESISTANCE OF THE SOLUTION

10.1. The frost resistance of the mortar is determined only in the cases specified in the project.

Solutions of grades 4; 10 and solutions prepared with air binders are not tested for frost resistance.

10.2. The solution is tested for frost resistance by repeated alternate freezing of cubes with an edge of 70.7 mm in a state of saturation with water at a temperature of minus 15-20 ° C and thawing them in water at a temperature of 15-20 ° C.

10.3. For testing, 6 sample cubes are prepared, of which 3 samples are subjected to freezing, and the remaining 3 samples are control samples.

10.4. The maximum number of cycles of alternating freezing and thawing, which the samples withstand during the test, are taken as the brand of the solution for frost resistance.

Frost resistance mortar grades should be adopted in accordance with the requirements of the current regulatory documentation.

10.5. Equipment

10.5.1. The following are used for testing:

freezer with forced ventilation and automatic temperature control within minus 15-20 ° С;

a container for saturating the samples with water with a device that maintains the temperature of the water in the vessel within the range of plus 15–20 ° C;

molds for making samples in accordance with GOST 22685-89.

By the decree of the State Committee of the USSR for Construction Affairs dated December 11, 1985 No. 214, the introduction period was established

01.07.86

This standard applies to mortar mixtures and building mortars made on mineral binders (cement, lime, gypsum, dissolving glass) used in all types of construction, except for hydraulic engineering.

The standard establishes methods for determining the following properties of a mortar mixture and mortar:

mobility, average density, delamination, water retention capacity, water separation of the mortar mixture;

The standard does not apply to solutions that are heat-resistant, chemically resistant and stressful.

1. GENERAL REQUIREMENTS

1.8. Before forming the samples, the inner surfaces of the molds are coated with a thin layer of grease.

1.9. All samples must be labeled. The marking must be indelible and must not damage the specimen.

1.10. The manufactured samples are measured with a caliper with an error of up to 0,1 mm.

1.11. In winter conditions, for testing a solution with antifreeze additives and without them, sampling and making samples should be carried out at the place of its application or preparation, and storage of samples in the same temperature and humidity conditions in which the solution is placed in the structure.

Samples should be stored on the shelf of a lockable mesh-walled inventory box with a waterproof roof.

1.12. All measuring instruments and parameters of the vibrating platform should be checked within the time frames stipulated by the metrological services of the State Standard.

1.13. The temperature of the room in which the tests are carried out should be (20 ± 2) ° С, relative air humidity 50-70%.

The temperature and humidity of the room are measured with an MV-4 aspiration psychrometer.

1.14. For testing mortar mixtures and solutions, vessels, spoons, and other devices must be made of steel, glass or plastic.

The use of products made of aluminum or galvanized steel and wood is not allowed.

1.15. The compressive strength of the mortar taken from the seams of the masonry is determined according to the method described in the appendix.

The tensile strength of the solution in bending and compression is determined in accordance with GOST 310.4-81.

The tensile strength of the solution when splitting is determined according to GOST 10180-90.

The bond strength is determined according to GOST 24992-81.

Shrinkage deformation is determined according to GOST 24544-81.

The water-separated mortar mixture is determined according to GOST 10181.0-81.

1.16. The results of tests of samples of mortar mixtures and samples of mortar are entered in the logbook, on the basis of which a document is drawn up characterizing the quality of the mortar.

2. DETERMINATION OF MOBILITY OF MORTAR MIXTURE

2.1. The mobility of the mortar mixture is characterized by the depth of immersion of the reference cone in it, measured in centimeters.

2.2. Equipment

2.2.1. The following are used for testing:

device for determining mobility (fig.);

steel bar diameter 12 mm, length 300 mm;

a trowel.

2.2.2. The reference cone of the instrument is made of sheet steel or plastic with a steel tip. The apex angle should be 30 ° ± 30 ".

The mass of the reference cone with the bar should be (300 ± 2) g.

Device for determining the mobility of a mortar mixture

1- tripod; 2 - scale; 3 - reference cone; 4 - barbell; 5 - holders;

8 - locking screw

laboratory scales in accordance with GOST 24104-88;

steel rod with a diameter of 12 mm, length 300 mm;

steel ruler 400 mm in accordance with GOST 427-75.

3.3.

3.3.1. Before testing, the vessel is pre-weighed with an error of up to 2 d. Then fill with excess mortar mixture.

3.3.2. The mortar mixture is compacted by bayonetting with a steel rod 25 times and 5-6 a multiple light tap on the table.

3.3.3. After compaction, the excess mortar mixture is cut off with a steel ruler. The surface is carefully leveled with the edges of the vessel. The walls of the measuring vessel are cleaned with a damp cloth from the solution that has fallen on them. Then the vessel with the solution mixture is weighed to the nearest 2 G.

3.4. Processing of results

3.4.1. Density of the mortar mixturer, g / cm 3, calculated by the formula

(1)

where m - weight of a measuring vessel with a mortar mixture, g;

m 1 - mass of the measuring vessel without mixture, g.

3.4.2. The density of the solution mixture is determined as the arithmetic mean of the results of two density determinations "of a mixture from one sample, differing from each other by no more than 5% from the smaller value.

If there is a greater discrepancy in the results, the determination is repeated on a new sample of the solution mixture.

3.4.3. The test results should be entered in the log in the form according to the appendix.

4. DETERMINATION OF SOLUTION MIXTURE

4.1. The delamination of the mortar mixture, which characterizes its connectivity under dynamic action, is determined by comparing the content of the aggregate mass in the lower and upper parts of the freshly formed sample to the dimensions 150x150x150 mm.

4.2. Equipment

4.2.1. The following are used for testing: 150x150x150 mm according to GOST 2 2685-89;

laboratory vibratory plate type 435 A;

laboratory scales in accordance with GOST 24104-88;

mesh sieve 0,14 mm;

baking sheet;

steel bar diameter 12 mm, length 300 mm.

4.2.2. The laboratory vibratory platform in a loaded state should provide vertical vibrations with a frequency 2900 ± 100 per minute and amplitude ( 0.5 ± 0.05) mm. The vibrating platform must have a device that, when vibrating, provides a rigid attachment of the mold with the solution to the table surface.

4.3. Testing

4.3.1. The mortar mixture is placed and compacted in a mold for control samples of dimensions 150x150x150 mm. After that, the compacted mortar mixture in the mold is subjected to vibration on a laboratory vibrating platform for 1 min.

4.3.2. After vibrating the upper layer of the solution with a height ( 7.5 ± 0.5) mm are taken from the mold onto a baking sheet, and the lower part of the sample is unloaded from the mold by tipping onto a second baking sheet.

4.3.3. Selected samples of the mortar mixture are weighed with an error of up to 2 g and subjected to wet sieving on a sieve with holes 0,14 mm.

With wet sieving, separate parts of the sample, laid on a sieve, are washed with a stream of clean water until the binder is completely removed. The rinsing of the mixture is considered complete when clean water flows out of the sieve.

4.3.4. The washed portions of filler are transferred to a clean baking sheet, dried to constant weight at temperature 105-110 ° С and weighed with an error up to 2 G.

4.4. Processing of results

4.4.1. Aggregate content in the upper (lower) parts of the compacted mortar mixture V the percentage is determined by the formula

(2)

where t 1 - the mass of the washed dried aggregate from the upper (lower) part of the sample, g;

m 2 is the mass of the solution mixture taken from the upper (lower) part of the sample, g.

4.4.2. The index of delamination of the mortar mixture P the percentage is determined by the formula

where D V- the absolute value of the difference between the content of the filler in the upper and lower parts of the sample,%;

å V- the total content of the filler of the upper and lower parts of the sample,%.

4.4.3. The stratification index for each sample of the solution mixture is determined twice and calculated with rounding to 1% as the arithmetic mean of the results of two determinations, differing from each other by no more than 20% from the lower value. If there is a greater discrepancy in the results, the determination is repeated on a new sample of the solution mixture.

4.4.4. The test results should be recorded in a logbook, which indicates:

date and time of testing;

place of sampling;

brand and type of solution;

results of private determinations;

arithmetic mean result.

5. DETERMINATION OF THE WATER-HOLDING CAPACITY OF THE SOLUTION MIXTURE

5.1. The water retention capacity is determined by testing a 12 mm thick layer of mortar laid on absorbent paper.

5.2. Apparatus and materials

5.2.1. The following are used for testing:

size blotter sheets 150 ´ 150 mm according to TU 13-7308001-758-88;

gauze pads size 250 ´ 350 mm according to GOST 11109-90;

metal ring inner diameter 100 mm, height 12 mm and wall thickness 5 mm;

glass plate size 150x150 mm, 5 mm thick;

laboratory scales in accordance with GOST 24104-88;

a device for determining the water-holding capacity of a mortar mixture (damn).

5.3. Test preparation and testing

5.3.1. Before the test 10 sheets of blotting paper are weighed with an error of up to 0,1 d, placed on a glass plate, a gauze cloth gasket is placed on top, a metal ring is installed and weighed again.

5.3.2. The thoroughly mixed mortar mixture is placed flush with the edges of the metal ring, leveled, weighed and left on 10 min.

5.3.3. The metal ring with the solution is carefully removed along with the gauze.

The blotter paper is weighed with an accuracy of up to 0,1 G.

Diagram of the device for determining the water-holding capacity of the mortar mixture

1 - a metal ring with a solution; 2 - 10 layers of blotting paper;

3 - glass plate; 4 - gauze layer

hydraulic press in accordance with GOST 28840-90;

steel diameter rod 12 mm, length 300 mm;

6.4. Test preparation

6.4.1. Samples from a mortar mixture with a mobility of up to 5 cm should be made in molds with a pallet.

The mold is filled with a solution in two layers. Compaction of the layers of solution in each compartment of the mold is performed 12 by pressing the spatula: 6 presses along one side in 6 - in the perpendicular direction.

The excess solution is cut flush with the edges of the mold with a steel ruler moistened with water and the surface is smoothed.

6.4.2. Samples from a mortar mixture with mobility 5 cm and more are made in molds without a pallet.

The mold is placed on a brick covered with newsprint soaked in water or other non-glued paper. The size of the paper should be such that it covers the side faces of the brick. Before use, bricks must be rubbed by hand one against the other to eliminate sharp irregularities. Use ordinary clay bricks with a moisture content of no more than 2 % and water absorption 10-15 % by weight. Bricks with cement marks on the edges reuse are not subject.

6.4.3. The molds are filled with a mortar mixture at one time with some excess and compacted by bayoning with a steel rod 25 times along a concentric circle from the center to the edges.

6.4.4. Under the conditions of winter masonry, for testing solutions with antifreeze additives and without antifreeze additives, for each test period and each controlled area, 6 samples are made, three of which are tested within the time required for floor control of the strength of the solution after 3 hours of thawing at a temperature not lower than ( 20 ± 2) ° C, and the remaining three samples are tested after thawing and subsequent 28 - daily hardening at a temperature not lower than ( 20 ± 2) ° C. The defrosting time must correspond to that indicated in table. ...

6.4.5. Forms filled with a mortar mixture on hydraulic binders are kept before stripping in a normal storage chamber at a temperature ( 20 ± 2) ° С and relative air humidity 95-100%, and molds filled with a mortar mixture on air binders, - indoors at temperature ( 20 ± 2) ° С and relative humidity ( 65 ± 10) %.

6.4.6. Samples are released from forms via ( 24 ± 2) hours after laying the mortar mixture.

Samples made from mortar mixtures prepared on slag Portland cements, pozzolanic Portland cements with set retarders, as well as winter masonry samples stored in the open air, are released from the molds through 2-3 days

6.4.7. After release from the molds, the samples should be stored at a temperature ( 20 ± 2) ° C. In this case, the following conditions must be observed: samples from solutions prepared on hydraulic binders during the first 3 days. should be stored in a normal storage room at relative humidity 95-100 %, and the time remaining before the test - indoors at relative humidity ( 65 ± 10)% (from solutions hardening in air) or in water (from solutions hardening in a humid environment); samples from solutions prepared with air binders should be stored indoors at relative humidity ( 65 ± 10)%.

6.4.8. In the absence of a normal storage chamber, it is allowed to store samples prepared on hydraulic binders in wet sand or sawdust.

6.4.9. When stored indoors, samples should be protected from drafts, heating with heating devices, etc.

6.4.10 Before the compression test (for subsequent determination of density), the samples are weighed with an error of up to 0,1 % and measured with a caliper with an error of up to 0,1 mm.

6.4.11. Samples stored in water should be removed from it no earlier than 10 minutes before testing and wiped off with a damp cloth.

Samples stored indoors should be cleaned with a hairbrush.

drying cabinet in accordance with OST 16.0.801.397-87;

steel rulers in accordance with GOST 427-75;

desiccator in accordance with GOST 25336-82;

anhydrous calcium chloride according to GOST 450-77 or sulfuric acid with a density 1,84 g / cm 3 in accordance with GOST 2184-77;

7.4. Test preparation

7.4.1. The density of the solution is determined by testing samples in a state of natural moisture or normalized moisture state: dry, air-dry, normal, water-saturated.

7.4.2. When determining the density of a solution in a state of natural moisture, the samples are tested immediately after they are taken or stored in a vapor-tight package or a sealed container, the volume of which exceeds the volume of the samples placed in it by no more than 2 times.

7.4.3. The density of the solution at the normalized humidity state is determined by testing the samples of the solution having the normalized humidity or arbitrary humidity with the subsequent recalculation of the results obtained to the normalized humidity according to the formula ().

7.4.4. When determining the density of a solution in a dry state, the samples are dried to constant weight in accordance with the requirements of cl.

7.4.5. When determining the density of a solution in an air-dry state, before testing, the samples shall withstand at least 28 days in a room at a temperature ( 25 ± 10) ° С and relative humidity ( 50 ± 20)%.

7.4.6. When determining the density of a solution under normal humidity conditions, the samples are stored 28 days in a normal hardening chamber, desiccator or other sealed container at a relative humidity of at least 95% and a temperature ( 20 ± 2) ° C.

7.4.7. When determining the density of a solution in a water-saturated state, the samples are saturated with water in accordance with the requirements of cl.

7.5. Testing

7.5.1. The volume of the samples is calculated by their geometric dimensions. The dimensions of the samples are determined with a caliper with an error of no more than 0,1 mm.

7.5.2. The mass of the samples is determined by weighing with an error of not more than 0.1%.

7.6. Processing of results

drying cabinet in accordance with OST 16.0.801.397-87;

desiccator in accordance with GOST 25336-82;

baking sheets;

calcium chloride according to GOST 450-77.

8.5. Testing

Gypsum solutions are dried at a temperature of 45-55 ° C.

The mass at which the results of two successive weighings differ by no more than 0.1% is considered constant. In this case, the time between weighings should be at least 4 hours.

8.5.2. Before re-weighing, the samples are cooled in a desiccator with anhydrous calcium chloride or together with an oven to room temperature.

8.5.3. Weighing is carried out with an error of up to 0,1 G.

8.6. Processing of results

8.6.1. The moisture content of the solution by weightW m as a percentage, calculated with an error of up to 0.1% according to the formula

(8)

where T v - mass of the solution sample before drying, g;

t with - mass of the solution sample after drying, g.

8.6.2. The moisture content of the solution by volumeW o as a percentage, calculated with an error of up to 0.1% according to the formula

(9)

where r O- the density of the dry solution, determined according to p.;

r v- the density of water, taken equal to 1 g / cm 3.

8.6.3. The moisture content of a solution of a series of samples is determined as the arithmetic mean of the results of determining the moisture content of individual solution samples.

8.6.4. The test results should be recorded in a logbook, which indicates:

place and time of sampling;

moisture state of the solution;

mortar age and test date;

sample labeling;

moisture content of the solution of samples (samples) and series by weight;

moisture content of the solution of samples (samples) and series by volume.

9. DETERMINATION OF WATER ABSORPTION OF SOLUTION

9.1. The water absorption of the solution is determined by testing the samples. The sizes and number of samples are taken in accordance with clause 7.1.

9.2. Apparatus and materials

9.2.1. The following are used for testing:

laboratory scales in accordance with GOST 24104-88;

drying cabinet in accordance with OST 16.0.801.397-87;

container for saturation of samples with water;

wire brush or abrasive stone.

9.3. Test preparation

9.3.1. The surface of the samples is cleaned of dust, dirt and traces of grease using a wire brush or an abrasive stone.

9.3.2. Samples are tested in a state of natural moisture or dried to constant weight.

10.6. Test preparation

10.6.1. Samples to be tested for frost resistance (main) should be numbered, inspected and noticed defects (minor edges or corners, chipping, etc.) should be entered in the test log.

10.6.2. The main samples should be tested for frost resistance at 28 days of age after being kept in a normal hardening chamber.

10.6.3. Control samples intended for compression tests must be stored in a normal hardening chamber at a temperature of (20 ± 2) ° С and a relative humidity of at least 90%.

10.6.4. The main samples of the solution intended for testing for frost resistance and control samples intended for determining the compressive strength at 28 days of age, before testing, must be saturated with water without preliminary drying by keeping them for 48 hours in water at a temperature of 15-20 ° WITH. In this case, the sample should be surrounded on all sides by a layer of water with a thickness of at least 20 mm. The saturation time in water is included in the total age of the solution.

10.7. Testing

10.7.1. Primary samples saturated with water should be placed in a freezer in special containers or placed on mesh shelves. The distance between the samples, as well as between the samples and the walls of containers and the overlying shelves, must be at least 50 mm.

10.7.2. The samples should be frozen in a freezer that allows the chamber with the samples to be cooled and maintain a temperature of minus 15-20 ° C in it. The temperature should be measured at half the height of the chamber.

10.7.3. Samples should be loaded into the chamber after cooling the air in it to a temperature not higher than minus 15 ° С. If, after loading the chamber, the temperature in it turns out to be higher than minus 15 ° С, then the beginning of freezing should be considered the moment when the air temperature reaches minus 15 ° С.

10.7.4. The duration of one freezing should be at least 4 hours.

10.7.5. Samples after unloading from freezer must be thawed in a bath of water at a temperature of 15-20 ° C for 3 hours.

10.7.6. Control examination of samples should be carried out in order to terminate the frost resistance test of a series of samples in which the surface of two out of three samples has visible damage (delamination, through cracks, spalling).

10.7.7. After alternating freezing and thawing of the samples, the main samples shall be compression tested.

10.7.8. Compression specimens should be tested in accordance with the requirements of Sec. of this standard.

10.7.9. Prior to the compression test, the master specimens are examined and the area of ​​edge damage is determined.

If there are signs of damage to the support faces of the samples (peeling, etc.), before testing, they should be leveled with a layer of quick-hardening compound no more than 2 mm thick. In this case, the samples should be tested 48 hours after pouring, and the first day the samples should be stored in a humid environment, and then in water at a temperature of 15-20 ° C.

10.7.10. Control samples should be tested for compression in a water-saturated state before freezing the main samples. The supporting surfaces of the specimens should be wiped off with a damp cloth before placing on the press.

10.7.11. When assessing frost resistance by weight loss after carrying out the required number of freezing and thawing cycles, the samples are weighed in a saturated state with an error of no more than 0.1%.

10.7.12. When assessing frost resistance by the degree of damage, the samples are examined every 5 cycles of alternating freezing and thawing. After thawing, the samples are examined every 5 cycles.

10.8. Processing of results

10.8.1. Frost resistance in terms of the loss of strength in compression of samples during alternating freezing and thawing is assessed by comparing the strength of the main and control samples in a state saturated with water.

Loss of specimen strengthDas a percentage, calculated by the formula

(12)

where Rcounter- the arithmetic mean of the ultimate compressive strength of control samples, MPa (kgf / cm 2);

Rmain - the arithmetic mean of the ultimate compressive strength of the main samples after testing them for frost resistance, MPa (kgf / cm 2).

The permissible value of the loss of strength of the samples in compression after their alternate freezing and thawing - no more 25 %.

10.8.2. Weight loss of specimens tested for frost resistance, M as a percentage, calculated by the formula

(13)

where m 1 - mass of a sample saturated with water before testing it for frost resistance, g;

m 2 is the mass of a sample saturated with water after testing it for frost resistance, g.

The weight loss of the samples after the frost resistance test is calculated as the arithmetic mean of the test results of the three samples.

Allowable weight loss of samples after alternate freezing and thawing - no more 5 %.

10.8.3. The following data should be indicated in the frost resistance test log of samples:

type and composition of the solution, design grade for frost resistance;

marking, date of manufacture and date of testing;

dimensions and weight of each sample before and after testing and weight loss in percent;

hardening conditions;

a description of the defects found in the samples prior to testing;

description external signs destruction and damage after testing;

ultimate compressive strength of each of the main and control samples and the change in strength in percent after testing for frost resistance;

number of freeze and thaw cycles.

APPENDIX 1

Mandatory

DETERMINATION OF THE STRENGTH OF THE MORTAR TAKEN FROM THE SEAMS

ON COMPRESSION

1. The strength of the solution is determined by compressing cubes with ribs 2-4 cm, made of two plates taken from horizontal joints of masonry or joints of large-panel structures.

2. The plates are made in the form of a square, the side of which is in 1,5 times should exceed the thickness of the plate, equal to the thickness of the seam.

3. Gluing plates of a solution to obtain cubes with edges of 2-4 cm and leveling their surfaces is carried out using a thin layer of gypsum dough ( 1-2 mm).

4. It is allowed to cut out samples-cubes from plates in the case when the thickness of the plate ensures obtaining the required rib size.

5. Samples should be tested one day after their manufacture.

6. Sample cubes from a solution with edges of length 3-4 cm is tested according to clause of this standard.

7. For testing sample cubes from a solution with ribs 2 cm, as well as thawed solutions, a small-sized desktop press of the PS type is used. Normal load range is 1,0-5,0 kN ( 100-500 kgf).

8. The strength of the solution is calculated according to clause of this standard. The strength of the solution shall be determined as the arithmetic mean of the test results of five samples.

9. To determine the strength of the solution in cubes with ribs 7,07 see the results of tests of cubes of summer and winter solutions, hardened after thawing, should be multiplied by the coefficient given in the table.

APPENDIX2

tests to determine mobility, average density

mortar and compressive strength, medium density

solution samples

Laboratory manager _____________ _______________________________

Responsible for manufacturing

and sample testing ________________________________________________

_____________

* The column "Notes" should indicate the defects of the samples: shells, foreign inclusions and their locations, the special nature of destruction, etc.

STATE STANDARD OF THE UNION OF SSR

CONSTRUCTION MORTARS

TEST METHODS

GOST 5802-86

MINSTROY OF RUSSIA

Moscow

STATE STANDARD OF THE UNION OF SSR

By the decree of the State Committee of the USSR for Construction Affairs dated December 11, 1985 No. 214, the introduction period was established

01.07.86

This standard applies to mortar mixtures and building mortars made on mineral binders (cement, lime, gypsum, dissolving glass) used in all types of construction, except for hydraulic engineering.

The standard establishes methods for determining the following properties of a mortar mixture and mortar:

mobility, average density, delamination, water retention capacity, water separation of the mortar mixture;

The standard does not apply to solutions that are heat-resistant, chemically resistant and stressful.

1. GENERAL REQUIREMENTS

1.8. Before forming the samples, the inner surfaces of the molds are coated with a thin layer of grease.

1.9. All samples must be labeled. The marking must be indelible and must not damage the specimen.

1.10. The manufactured samples are measured with a caliper with an error of up to 0,1 mm.

1.11. In winter conditions, for testing a solution with antifreeze additives and without them, sampling and making samples should be carried out at the place of its application or preparation, and storage of samples in the same temperature and humidity conditions in which the solution is placed in the structure.

Samples should be stored on the shelf of a lockable mesh-walled inventory box with a waterproof roof.

1.12. All measuring instruments and parameters of the vibrating platform should be checked within the time frames stipulated by the metrological services of the State Standard.

1.13. The temperature of the room in which the tests are carried out should be (20 ± 2) ° С, relative air humidity 50-70%.

The temperature and humidity of the room are measured with an MV-4 aspiration psychrometer.

1.14. For testing mortar mixtures and solutions, vessels, spoons, and other devices must be made of steel, glass or plastic.

The use of products made of aluminum or galvanized steel and wood is not allowed.

1.15. The compressive strength of the mortar taken from the seams of the masonry is determined according to the method described in the appendix.

The tensile strength of the solution in bending and compression is determined in accordance with GOST 310.4-81.

The tensile strength of the solution when splitting is determined according to GOST 10180-90.

The bond strength is determined according to GOST 24992-81.

Shrinkage deformation is determined according to GOST 24544-81.

The water-separated mortar mixture is determined according to GOST 10181.0-81.

1.16. The results of tests of samples of mortar mixtures and samples of mortar are entered in the logbook, on the basis of which a document is drawn up characterizing the quality of the mortar.

2. DETERMINATION OF MOBILITY OF MORTAR MIXTURE

2.1. The mobility of the mortar mixture is characterized by the depth of immersion of the reference cone in it, measured in centimeters.

2.2. Equipment

2.2.1. The following are used for testing:

device for determining mobility (fig.);

steel bar diameter 12 mm, length 300 mm;

a trowel.

2.2.2. The reference cone of the instrument is made of sheet steel or plastic with a steel tip. The apex angle should be 30 ° ± 30 ".

The mass of the reference cone with the bar should be (300 ± 2) g.

Device for determining the mobility of a mortar mixture

1- tripod; 2 - scale; 3 - reference cone; 4 - barbell; 5 - holders;

8 - locking screw

laboratory scales in accordance with GOST 24104-88;

steel rod with a diameter of 12 mm, length 300 mm;

steel ruler 400 mm in accordance with GOST 427-75.

3.3.

3.3.1. Before testing, the vessel is pre-weighed with an error of up to 2 d. Then fill with excess mortar mixture.

3.3.2. The mortar mixture is compacted by bayonetting with a steel rod 25 times and 5-6 a multiple light tap on the table.

3.3.3. After compaction, the excess mortar mixture is cut off with a steel ruler. The surface is carefully leveled with the edges of the vessel. The walls of the measuring vessel are cleaned with a damp cloth from the solution that has fallen on them. Then the vessel with the solution mixture is weighed to the nearest 2 G.

3.4. Processing of results

3.4.1. Density of the mortar mixturer, g / cm 3, calculated by the formula

(1)

where m - weight of a measuring vessel with a mortar mixture, g;

m 1 - mass of the measuring vessel without mixture, g.

3.4.2. The density of the solution mixture is determined as the arithmetic mean of the results of two density determinations "of a mixture from one sample, differing from each other by no more than 5% from the smaller value.

If there is a greater discrepancy in the results, the determination is repeated on a new sample of the solution mixture.

3.4.3. The test results should be entered in the log in the form according to the appendix.

4. DETERMINATION OF SOLUTION MIXTURE

4.1. The delamination of the mortar mixture, which characterizes its connectivity under dynamic action, is determined by comparing the content of the aggregate mass in the lower and upper parts of the freshly formed sample to the dimensions 150x150x150 mm.

4.2. Equipment

4.2.1. The following are used for testing: 150x150x150 mm according to GOST 2 2685-89;

laboratory vibratory plate type 435 A;

laboratory scales in accordance with GOST 24104-88;

mesh sieve 0,14 mm;

baking sheet;

steel bar diameter 12 mm, length 300 mm.

4.2.2. The laboratory vibratory platform in a loaded state should provide vertical vibrations with a frequency 2900 ± 100 per minute and amplitude ( 0.5 ± 0.05) mm. The vibrating platform must have a device that, when vibrating, provides a rigid attachment of the mold with the solution to the table surface.

4.3. Testing

4.3.1. The mortar mixture is placed and compacted in a mold for control samples of dimensions 150x150x150 mm. After that, the compacted mortar mixture in the mold is subjected to vibration on a laboratory vibrating platform for 1 min.

4.3.2. After vibrating the upper layer of the solution with a height ( 7.5 ± 0.5) mm are taken from the mold onto a baking sheet, and the lower part of the sample is unloaded from the mold by tipping onto a second baking sheet.

4.3.3. Selected samples of the mortar mixture are weighed with an error of up to 2 g and subjected to wet sieving on a sieve with holes 0,14 mm.

With wet sieving, separate parts of the sample, laid on a sieve, are washed with a stream of clean water until the binder is completely removed. The rinsing of the mixture is considered complete when clean water flows out of the sieve.

4.3.4. The washed portions of filler are transferred to a clean baking sheet, dried to constant weight at temperature 105-110 ° С and weighed with an error up to 2 G.

4.4. Processing of results

4.4.1. Aggregate content in the upper (lower) parts of the compacted mortar mixture V the percentage is determined by the formula

(2)

where t 1 - the mass of the washed dried aggregate from the upper (lower) part of the sample, g;

m 2 is the mass of the solution mixture taken from the upper (lower) part of the sample, g.

4.4.2. The index of delamination of the mortar mixture P the percentage is determined by the formula

where D V- the absolute value of the difference between the content of the filler in the upper and lower parts of the sample,%;

å V- the total content of the filler of the upper and lower parts of the sample,%.

4.4.3. The stratification index for each sample of the solution mixture is determined twice and calculated with rounding to 1% as the arithmetic mean of the results of two determinations, differing from each other by no more than 20% from the lower value. If there is a greater discrepancy in the results, the determination is repeated on a new sample of the solution mixture.

4.4.4. The test results should be recorded in a logbook, which indicates:

date and time of testing;

place of sampling;

brand and type of solution;

results of private determinations;

arithmetic mean result.

5. DETERMINATION OF THE WATER-HOLDING CAPACITY OF THE SOLUTION MIXTURE

5.1. The water retention capacity is determined by testing a 12 mm thick layer of mortar laid on absorbent paper.

5.2. Apparatus and materials

5.2.1. The following are used for testing:

size blotter sheets 150 ´ 150 mm according to TU 13-7308001-758-88;

gauze pads size 250 ´ 350 mm according to GOST 11109-90;

metal ring inner diameter 100 mm, height 12 mm and wall thickness 5 mm;

glass plate size 150x150 mm, 5 mm thick;

laboratory scales in accordance with GOST 24104-88;

a device for determining the water-holding capacity of a mortar mixture (damn).

5.3. Test preparation and testing

5.3.1. Before the test 10 sheets of blotting paper are weighed with an error of up to 0,1 d, placed on a glass plate, a gauze cloth gasket is placed on top, a metal ring is installed and weighed again.

5.3.2. The thoroughly mixed mortar mixture is placed flush with the edges of the metal ring, leveled, weighed and left on 10 min.

5.3.3. The metal ring with the solution is carefully removed along with the gauze.

The blotter paper is weighed with an accuracy of up to 0,1 G.

Diagram of the device for determining the water-holding capacity of the mortar mixture

1 - a metal ring with a solution; 2 - 10 layers of blotting paper;

3 - glass plate; 4 - gauze layer

hydraulic press in accordance with GOST 28840-90;

steel diameter rod 12 mm, length 300 mm;

6.4. Test preparation

6.4.1. Samples from a mortar mixture with a mobility of up to 5 cm should be made in molds with a pallet.

The mold is filled with a solution in two layers. Compaction of the layers of solution in each compartment of the mold is performed 12 by pressing the spatula: 6 presses along one side in 6 - in the perpendicular direction.

The excess solution is cut flush with the edges of the mold with a steel ruler moistened with water and the surface is smoothed.

6.4.2. Samples from a mortar mixture with mobility 5 cm and more are made in molds without a pallet.

The mold is placed on a brick covered with newsprint soaked in water or other non-glued paper. The size of the paper should be such that it covers the side faces of the brick. Before use, bricks must be rubbed by hand one against the other to eliminate sharp irregularities. Use ordinary clay bricks with a moisture content of no more than 2 % and water absorption 10-15 % by weight. Bricks with traces of cement on the edges cannot be reused.

6.4.3. The molds are filled with a mortar mixture at one time with some excess and compacted by bayoning with a steel rod 25 times along a concentric circle from the center to the edges.

6.4.4. Under the conditions of winter masonry, for testing solutions with antifreeze additives and without antifreeze additives, for each test period and each controlled area, 6 samples are made, three of which are tested within the time required for floor control of the strength of the solution after 3 hours of thawing at a temperature not lower than ( 20 ± 2) ° C, and the remaining three samples are tested after thawing and subsequent 28 - daily hardening at a temperature not lower than ( 20 ± 2) ° C. The defrosting time must correspond to that indicated in table. ...

6.4.5. Forms filled with a mortar mixture on hydraulic binders are kept before stripping in a normal storage chamber at a temperature ( 20 ± 2) ° С and relative air humidity 95-100%, and molds filled with a mortar mixture on air binders, - indoors at temperature ( 20 ± 2) ° С and relative humidity ( 65 ± 10) %.

6.4.6. Samples are released from forms via ( 24 ± 2) hours after laying the mortar mixture.

Samples made from mortar mixtures prepared on slag Portland cements, pozzolanic Portland cements with set retarders, as well as winter masonry samples stored in the open air, are released from the molds through 2-3 days

6.4.7. After release from the molds, the samples should be stored at a temperature ( 20 ± 2) ° C. In this case, the following conditions must be observed: samples from solutions prepared on hydraulic binders during the first 3 days. should be stored in a normal storage room at relative humidity 95-100 %, and the time remaining before the test - indoors at relative humidity ( 65 ± 10)% (from solutions hardening in air) or in water (from solutions hardening in a humid environment); samples from solutions prepared with air binders should be stored indoors at relative humidity ( 65 ± 10)%.

6.4.8. In the absence of a normal storage chamber, it is allowed to store samples prepared on hydraulic binders in wet sand or sawdust.

6.4.9. When stored indoors, samples should be protected from drafts, heating with heating devices, etc.

6.4.10 Before the compression test (for subsequent determination of density), the samples are weighed with an error of up to 0,1 % and measured with a caliper with an error of up to 0,1 mm.

6.4.11. Samples stored in water should be removed from it no earlier than 10 minutes before testing and wiped off with a damp cloth.

Samples stored indoors should be cleaned with a hairbrush.

drying cabinet in accordance with OST 16.0.801.397-87;

steel rulers in accordance with GOST 427-75;

desiccator in accordance with GOST 25336-82;

anhydrous calcium chloride according to GOST 450-77 or sulfuric acid with a density 1,84 g / cm 3 in accordance with GOST 2184-77;

7.4. Test preparation

7.4.1. The density of the solution is determined by testing samples in a state of natural moisture or normalized moisture state: dry, air-dry, normal, water-saturated.

7.4.2. When determining the density of a solution in a state of natural moisture, the samples are tested immediately after they are taken or stored in a vapor-tight package or a sealed container, the volume of which exceeds the volume of the samples placed in it by no more than 2 times.

7.4.3. The density of the solution at the normalized humidity state is determined by testing the samples of the solution having the normalized humidity or arbitrary humidity with the subsequent recalculation of the results obtained to the normalized humidity according to the formula ().

7.4.4. When determining the density of a solution in a dry state, the samples are dried to constant weight in accordance with the requirements of cl.

7.4.5. When determining the density of a solution in an air-dry state, before testing, the samples shall withstand at least 28 days in a room at a temperature ( 25 ± 10) ° С and relative humidity ( 50 ± 20)%.

7.4.6. When determining the density of a solution under normal humidity conditions, the samples are stored 28 days in a normal hardening chamber, desiccator or other sealed container at a relative humidity of at least 95% and a temperature ( 20 ± 2) ° C.

7.4.7. When determining the density of a solution in a water-saturated state, the samples are saturated with water in accordance with the requirements of cl.

7.5. Testing

7.5.1. The volume of the samples is calculated by their geometric dimensions. The dimensions of the samples are determined with a caliper with an error of no more than 0,1 mm.

7.5.2. The mass of the samples is determined by weighing with an error of not more than 0.1%.

7.6. Processing of results

drying cabinet in accordance with OST 16.0.801.397-87;

desiccator in accordance with GOST 25336-82;

baking sheets;

calcium chloride according to GOST 450-77.

8.5. Testing

Gypsum solutions are dried at a temperature of 45-55 ° C.

The mass at which the results of two successive weighings differ by no more than 0.1% is considered constant. In this case, the time between weighings should be at least 4 hours.

8.5.2. Before re-weighing, the samples are cooled in a desiccator with anhydrous calcium chloride or together with an oven to room temperature.

8.5.3. Weighing is carried out with an error of up to 0,1 G.

8.6. Processing of results

8.6.1. The moisture content of the solution by weightW m

(8)

where T v - mass of the solution sample before drying, g;

t with - mass of the solution sample after drying, g.

8.6.2. The moisture content of the solution by volumeW o as a percentage, calculated with an error of up to 0.1% according to the formula

(9)

where r O- the density of the dry solution, determined according to p.;

r v- the density of water, taken equal to 1 g / cm 3.

8.6.3. The moisture content of a solution of a series of samples is determined as the arithmetic mean of the results of determining the moisture content of individual solution samples.

8.6.4. The test results should be recorded in a logbook, which indicates:

place and time of sampling;

moisture state of the solution;

mortar age and test date;

sample labeling;

moisture content of the solution of samples (samples) and series by weight;

moisture content of the solution of samples (samples) and series by volume.

9. DETERMINATION OF WATER ABSORPTION OF SOLUTION

9.1. The water absorption of the solution is determined by testing the samples. The sizes and number of samples are taken in accordance with clause 7.1.

9.2. Apparatus and materials

9.2.1. The following are used for testing:

laboratory scales in accordance with GOST 24104-88;

drying cabinet in accordance with OST 16.0.801.397-87;

container for saturation of samples with water;

wire brush or abrasive stone.

9.3. Test preparation

9.3.1. The surface of the samples is cleaned of dust, dirt and traces of grease using a wire brush or an abrasive stone.

9.3.2. Samples are tested in a state of natural moisture or dried to constant weight.

10.6. Test preparation

10.6.1. Samples to be tested for frost resistance (main) should be numbered, inspected and noticed defects (minor edges or corners, chipping, etc.) should be entered in the test log.

10.6.2. The main samples should be tested for frost resistance at 28 days of age after being kept in a normal hardening chamber.

10.6.3. Control samples intended for compression tests must be stored in a normal hardening chamber at a temperature of (20 ± 2) ° С and a relative humidity of at least 90%.

10.6.4. The main samples of the solution intended for testing for frost resistance and control samples intended for determining the compressive strength at 28 days of age, before testing, must be saturated with water without preliminary drying by keeping them for 48 hours in water at a temperature of 15-20 ° WITH. In this case, the sample should be surrounded on all sides by a layer of water with a thickness of at least 20 mm. The saturation time in water is included in the total age of the solution.

10.7. Testing

10.7.1. Primary samples saturated with water should be placed in a freezer in special containers or placed on mesh shelves. The distance between the samples, as well as between the samples and the walls of containers and the overlying shelves, must be at least 50 mm.

10.7.2. The samples should be frozen in a freezer that allows the chamber with the samples to be cooled and maintain a temperature of minus 15-20 ° C in it. The temperature should be measured at half the height of the chamber.

10.7.3. Samples should be loaded into the chamber after cooling the air in it to a temperature not higher than minus 15 ° С. If, after loading the chamber, the temperature in it turns out to be higher than minus 15 ° С, then the beginning of freezing should be considered the moment when the air temperature reaches minus 15 ° С.

10.7.4. The duration of one freezing should be at least 4 hours.

10.7.5. After unloading from the freezer, the samples should be thawed in a bath with water at a temperature of 15-20 ° C for 3 hours.

10.7.6. Control examination of samples should be carried out in order to terminate the frost resistance test of a series of samples in which the surface of two out of three samples has visible damage (delamination, through cracks, spalling).

10.7.7. After alternating freezing and thawing of the samples, the main samples shall be compression tested.

10.7.8. Compression specimens should be tested in accordance with the requirements of Sec. of this standard.

10.7.9. Prior to the compression test, the master specimens are examined and the area of ​​edge damage is determined.

If there are signs of damage to the support faces of the samples (peeling, etc.), before testing, they should be leveled with a layer of quick-hardening compound no more than 2 mm thick. In this case, the samples should be tested 48 hours after pouring, and the first day the samples should be stored in a humid environment, and then in water at a temperature of 15-20 ° C.

10.7.10. Control samples should be tested for compression in a water-saturated state before freezing the main samples. The supporting surfaces of the specimens should be wiped off with a damp cloth before placing on the press.

10.7.11. When assessing frost resistance by weight loss after carrying out the required number of freezing and thawing cycles, the samples are weighed in a saturated state with an error of no more than 0.1%.

10.7.12. When assessing frost resistance by the degree of damage, the samples are examined every 5 cycles of alternating freezing and thawing. After thawing, the samples are examined every 5 cycles.

10.8. Processing of results

10.8.1. Frost resistance in terms of the loss of strength in compression of samples during alternating freezing and thawing is assessed by comparing the strength of the main and control samples in a state saturated with water.

Loss of specimen strengthD

(12)

where Rcounter- the arithmetic mean of the ultimate compressive strength of control samples, MPa (kgf / cm 2);

Rmain - the arithmetic mean of the ultimate compressive strength of the main samples after testing them for frost resistance, MPa (kgf / cm 2).

The permissible value of the loss of strength of the samples in compression after their alternate freezing and thawing - no more 25 %.

10.8.2. Weight loss of specimens tested for frost resistance, M as a percentage, calculated by the formula

(13)

where m 1 - mass of a sample saturated with water before testing it for frost resistance, g;

m 2 is the mass of a sample saturated with water after testing it for frost resistance, g.

The weight loss of the samples after the frost resistance test is calculated as the arithmetic mean of the test results of the three samples.

Allowable weight loss of samples after alternate freezing and thawing - no more 5 %.

10.8.3. The following data should be indicated in the frost resistance test log of samples:

type and composition of the solution, design grade for frost resistance;

marking, date of manufacture and date of testing;

dimensions and weight of each sample before and after testing and weight loss in percent;

hardening conditions;

a description of the defects found in the samples prior to testing;

description of external signs of destruction and damage after testing;

ultimate compressive strength of each of the main and control samples and the change in strength in percent after testing for frost resistance;

number of freeze and thaw cycles.

APPENDIX 1

Mandatory

DETERMINATION OF THE STRENGTH OF THE MORTAR TAKEN FROM THE SEAMS

ON COMPRESSION

1. The strength of the solution is determined by compressing cubes with ribs 2-4 cm, made of two plates taken from horizontal joints of masonry or joints of large-panel structures.

2. The plates are made in the form of a square, the side of which is in 1,5 times should exceed the thickness of the plate, equal to the thickness of the seam.

3. Gluing plates of a solution to obtain cubes with edges of 2-4 cm and leveling their surfaces is carried out using a thin layer of gypsum dough ( 1-2 mm).

4. It is allowed to cut out samples-cubes from plates in the case when the thickness of the plate ensures obtaining the required rib size.

5. Samples should be tested one day after their manufacture.

6. Sample cubes from a solution with edges of length 3-4 cm is tested according to clause of this standard.

7. For testing sample cubes from a solution with ribs 2 cm, as well as thawed solutions, a small-sized desktop press of the PS type is used. Normal load range is 1,0-5,0 kN ( 100-500 kgf).

8. The strength of the solution is calculated according to clause of this standard. The strength of the solution shall be determined as the arithmetic mean of the test results of five samples.

9. To determine the strength of the solution in cubes with ribs 7,07 see the results of tests of cubes of summer and winter solutions, hardened after thawing, should be multiplied by the coefficient given in the table.

APPENDIX2

tests to determine mobility, average density

mortar and compressive strength, medium density

solution samples

Laboratory manager _____________ _______________________________

Responsible for manufacturing

and sample testing ________________________________________________

_____________

* The column "Notes" should indicate the defects of the samples: shells, foreign inclusions and their locations, the special nature of destruction, etc.

GOST 5802-86

UDC 666.971.001.4:006.354

Group W19

INTERSTATE STANDARD

CONSTRUCTION MORTARS

TEST METHODS

Mortars. Test methods.

Date of introduction 07/01/86

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the Central Research Institute building structures(TsNIISK named after Kucherenko) Gosstroy of the USSR

2. APPROVED AND PUT INTO EFFECT by the Decree of the State Committee of the USSR for Construction Affairs dated 11.12.85 No. 214

3. REPLACE GOST 5802-78

4. REFERENCE REGULATORY AND TECHNICAL DOCUMENTS

5. REPUBLICATION. October 2002

This standard applies to mortar mixtures and building mortars made on mineral binders (cement, lime, gypsum, dissolving glass) used in all types of construction, except for hydraulic engineering.

The standard establishes methods for determining the following properties of a mortar mixture and mortar:

Mobility, average density, delamination, water retention capacity, water separation of the mortar mixture;

The standard does not apply to solutions that are heat-resistant, chemically resistant and straining solutions.

1. GENERAL REQUIREMENTS

1.1. Determination of the mobility, density of the mortar mixture and the compressive strength of the mortar is mandatory for all types of mortars. Other properties of mortar mixtures and mortar are determined in the cases provided for by the project or the rules for the production of work.

1.2. Samples for testing the mortar mixture and making samples are taken before the setting of the mortar mixture begins.

1.3. Samples should be taken from the mixer at the end of the mixing process, at the place of application of the solution from Vehicle or work box.

Samples are taken from at least three locations at different depths.

The sample volume must be at least 3 liters.

1.4. The taken sample must be additionally moved within 30 s before testing.

1.5. The test of the mortar mixture should be started no later than 10 minutes after sampling.

1.6. The test of the hardened solutions is carried out on samples. The shape and dimensions of the samples, depending on the type of test, must correspond to those indicated in table. one.

Table 1

Note. During production control of solutions, which are simultaneously required for tensile bending and compressive strength, it is allowed to determine the compressive strength of the solution by testing the halves of prism specimens obtained after bending test of prism specimens in accordance with GOST 310.4.

1.7. The deviation of the dimensions of the molded samples along the length of the edges of the cubes, the sides of the cross-section of the prisms indicated in table. 1 should not exceed 0.7 mm.

1.8. Before forming the samples, the inner surfaces of the molds are coated with a thin layer of grease.

1.9. All samples must be labeled. The marking must be indelible and must not damage the specimen.

1.10. The manufactured samples are measured with a caliper with an error of up to 0.1 mm.

1.11. In winter conditions, for testing a solution with antifreeze additives and without them, sampling and making samples should be carried out at the place of its application or preparation, and storage of samples in the same temperature and humidity conditions in which the solution is placed in the structure.

Samples should be stored on the shelf of a lockable mesh-walled inventory box with a waterproof roof.

1.12. All measuring instruments and parameters of the vibrating platform should be checked within the time frames stipulated by the metrological services of the State Standard.

1.13. The temperature of the room in which the tests are carried out should be (20 ± 2) ° С, relative air humidity 50-70%.

The temperature and humidity of the room are measured with an MV-4 aspiration psychrometer.

1.14. For testing mortar mixtures and solutions, vessels, spoons, and other devices must be made of steel, glass or plastic.

The use of products made of aluminum or galvanized steel and wood is not allowed.

1.15. The compressive strength of the mortar taken from the seams of the masonry is determined according to the method described in Appendix 1.

The tensile strength of the solution in bending and compression is determined in accordance with GOST 310.4.

The tensile strength of the solution when splitting is determined according to GOST 10180.

The adhesion strength is determined according to GOST 24992.

Shrinkage deformation is determined according to GOST 24544.

The water-separated mortar mixture is determined according to GOST 10181.

1.16. The results of tests of samples of mortar mixtures and samples of mortar are entered in the logbook, on the basis of which a document is drawn up characterizing the quality of the mortar.

2. DETERMINATION OF MOBILITY OF MORTAR MIXTURE

2.1. The mobility of the mortar mixture is characterized by the depth of immersion of the reference cone in it, measured in centimeters.

2.2. Equipment

2.2.1. The following are used for testing:

device for determining mobility (Fig. 1);

Device for determining the mobility of a mortar mixture

1 - tripod; 2 - scale; 3 - reference cone; 4 - barbell; 5 - holders;

6 - guides; 7 - a vessel for a mortar mixture; 8 - locking screw

2.2.2. The reference cone of the instrument is made of sheet steel or plastic with a steel tip. The apex angle should be 30 ° ± 30 " .

The mass of the reference cone with the bar should be (300 ± 2) g.

2.3. Test preparation

2.3.1. All surfaces of the cone and vessel in contact with the mortar mixture should be cleaned of dirt and wiped with a damp cloth.

2.4. Testing

2.4.1. The amount of immersion of the cone is determined in the sequence shown below.

The device is installed on a horizontal surface and the freedom of sliding of the rod is checked. 4 in guides 6.

2.4.2. Vessel 7 fill with a mortar mixture 1 cm below its edges and compact it by bayoning with a steel rod 25 times and 5-6 times lightly tapping on the table, after which the vessel is placed on the device platform.

2.4.3. Tip of the cone 3 bring into contact with the surface of the solution in the vessel, fix the cone bar with a locking screw 8 and make the first reading on the scale. Then release the locking screw.

2.4.4. The cone should be immersed in the mortar mixture freely. The second reading is taken on the scale 1 min after the beginning of the immersion of the cone.

2.4.5. The immersion depth of the cone, measured with an error of up to 1 mm, is determined as the difference between the first and second readings.

2.5. Processing of results

2.5.1. The immersion depth of the cone is estimated from the results of two tests on different samples of the mortar mixture of the same batch as the arithmetic mean of them and rounded off.

2.5.2. The difference in the indices of individual tests should not exceed 20 mm. If the difference is more than 20 mm, then the tests should be repeated on a new sample of the mortar mixture.

2.5.3. The test results are entered in the journal in the form in accordance with Appendix 2.

3. DETERMINATION OF THE DENSITY OF THE MORTAR MIXTURE

3.1. The density of the mortar mixture is characterized by the ratio of the mass of the compacted mortar mixture to its volume and is expressed in g / cm 3.

3.2. Equipment

3.2.1. The following are used for testing:

a steel cylindrical vessel with a capacity of 1000 + 2 ml (Fig. 2);

steel rod with a diameter of 12 mm, 300 mm long;

steel ruler 400 mm in accordance with GOST 427.

Steel cylindrical vessel

3.3. Test preparation and testing

3.3.1. Before the test, the vessel is preliminarily weighed with an error of up to 2 g. Then it is filled with an excess of the solution mixture.

3.3.2. The mortar mixture is compacted by bayonetting with a steel rod 25 times and 5-6 times lightly tapping on the table.

3.3.3. After compaction, the excess mortar mixture is cut off with a steel ruler. The surface is carefully leveled with the edges of the vessel. The walls of the measuring vessel are cleaned with a damp cloth from the solution that has fallen on them. Then weigh the vessel with the solution mixture to the nearest 2 g.

3.4. Processing of results

3.4.1. The density of the mortar mixture r, g / cm 3, is calculated by the formula

where m - weight of a measuring vessel with a mortar mixture, g;

m 1 - weight of the measuring vessel without mixture, g.

3.4.2. The density of the solution mixture is determined as the arithmetic mean of the results of two determinations of the density of the mixture from one sample, differing from each other by no more than 5% from the lower value.

If there is a greater discrepancy in the results, the determination is repeated on a new sample of the solution mixture.

3.4.3. The test results must be entered in the log in the form in accordance with Appendix 2.

4. DETERMINATION OF SOLUTION MIXTURE

4.1. The delamination of the mortar mixture, which characterizes its cohesion under dynamic action, is determined by comparing the content of the aggregate mass in the lower and upper parts of a freshly formed sample with dimensions of 150x150x150 mm.

4.2. Equipment

4.2.1. The following are used for testing:

steel forms with dimensions of 150x150x150 mm in accordance with GOST 22685;

laboratory vibratory platform, type 435A;

laboratory scales in accordance with GOST 24104;

a sieve with a mesh of 0.14 mm;

baking sheet;

steel rod with a diameter of 12 mm, 300 mm long.

4.2.2. The laboratory vibrating platform in a loaded state should provide vertical vibrations with a frequency of 2900 ± 100 per minute and an amplitude of (0.5 ± 0.05) mm. The vibrating platform should have a device that, when vibrating, provides a rigid attachment of the mold with the solution to the table surface.

4.3. Testing

4.3.1. The mortar mixture is placed and compacted in a mold for control samples with dimensions of 150x150x150 mm. After that, the compacted mortar mixture in the mold is subjected to vibration on a laboratory vibrating platform for 1 min.

4.3.2. After vibration, the upper layer of the solution with a height of (7.5 ± 0.5) mm is taken from the mold onto a baking sheet, and the lower part of the sample is unloaded from the mold by tipping onto a second baking sheet.

4.3.3. The selected samples of the solution mixture are weighed with an error of up to 2 g and subjected to wet sieving on a sieve with holes of 0.14 mm.

With wet sieving, separate parts of the sample, laid on a sieve, are washed with a stream of clean water until the binder is completely removed. The rinsing of the mixture is considered complete when clean water flows out of the sieve.

4.3.4. The washed portions of the filler are transferred to a clean baking sheet, dried to constant weight at a temperature of 105-110 ° C and weighed with an error of up to 2 g.

4.4. Processing of results

where T 1 - the mass of the washed dried aggregate from the upper (lower) part of the sample, g;

m 2 - mass of the solution mixture taken from the upper (lower) part of the sample, g.

4.4.2. The index of delamination of the mortar mixture P the percentage is determined by the formula

where D V- the absolute value of the difference between the content of the filler in the upper and lower parts of the sample,%;

å V - the total content of the filler of the upper and lower parts of the sample,%.

4.4.3. The stratification index for each sample of the solution mixture is determined twice and calculated with rounding to 1% as the arithmetic mean of the results of two determinations, differing from each other by no more than 20% from the lower value. If there is a greater discrepancy in the results, the determination is repeated on a new sample of the solution mixture.

4.4.4. The test results should be recorded in a logbook, which indicates:

date and time of testing;

place of sampling;

brand and type of solution;

results of private determinations;

arithmetic mean result.

5. DETERMINATION OF THE WATER-HOLDING CAPACITY OF THE SOLUTION MIXTURE

5.1. The water retention capacity is determined by testing a 12 mm thick layer of mortar laid on absorbent paper.

5.2. Apparatus and materials

5.2.1. The following are used for testing:

sheets of blotting paper 150X150 mm in size according to TU 13-7308001-758;

pads made of gauze fabric with a size of 250X350 mm in accordance with GOST 11109;

metal ring with an inner diameter of 100 mm, a height of 12 mm and a wall thickness of 5 mm;

a glass plate measuring 150x150 mm, 5 mm thick;

laboratory scales in accordance with GOST 24104;

a device for determining the water-holding capacity of a mortar mixture (Fig. 3).

Diagram of the device for determining the water-holding capacity of the mortar mixture

1 - a metal ring with a solution; 2 - 10 layers of blotting paper;

3 - glass plate; 4 - gauze layer

5.3. Test preparation and testing

5.3.1. Before testing, 10 sheets of blotting paper are weighed with an error of up to 0.1 g, placed on a glass plate, a gauze cloth pad is placed on top, a metal ring is installed and weighed again.

5.3.2. The thoroughly mixed mortar mixture is placed flush with the edges of the metal ring, leveled, weighed and left for 10 minutes.

5.3.3. The metal ring with the solution is carefully removed along with the gauze.

The blotter paper is weighed with an error of up to 0.1 g.

5.4. Processing of results

5.4.1. Water-holding capacity of the mortar mixture V is determined by the percentage of water in the sample before and after the experiment according to the formula

(4)

where T 1 - mass of blotting paper before testing, g;

T 2 - mass of blotting paper after testing, g;

m 3 - weight of the installation without mortar mixture, g;

T 4 - weight of the installation with the mortar mixture, g.

5.4.2. The water-holding capacity of the solution mixture is determined twice for each sample of the solution mixture and is calculated as the arithmetic mean of the results of two determinations that differ from each other by no more than 20% from the lower value.

5.4.3. The test results should be recorded in a logbook, which indicates:

date and time of testing;

place of sampling;

brand and type of mortar mixture;

the results of particular definitions and the arithmetic mean.

6. DETERMINATION OF THE COMPRESSION STRENGTH OF A MORTAR

6.1. The compressive strength of the solution should be determined on cube samples with dimensions of 70.7x70.7x70.7 mm at the age established in the standard or technical conditions for this type of solution. Three samples are made for each test period.

6.2. Sampling and general technical requirements for the method for determining the compressive strength - according to paragraphs. 1.1-1.14.

6.3. Equipment

6.3.1. The following are used for testing:

Detachable steel molds with and without pallets in accordance with GOST 22685;

Hydraulic press in accordance with GOST 28840;

Calipers in accordance with GOST 166;

Steel rod with a diameter of 12 mm, a length of 300 mm;

Spatula (Fig. 4).

Spatula for compaction of mortar mixture

6.4. Test preparation

6.4.1. Samples from a mortar mixture with a mobility of up to 5 cm should be made in molds with a tray.

The mold is filled with a solution in two layers. Compaction of the layers of mortar in each compartment of the mold is carried out with 12 spatula pushes: six pushes along one side and six pushes - in the perpendicular direction.

The excess solution is cut flush with the edges of the mold with a steel ruler moistened with water and the surface is smoothed.

6.4.2. Samples from a mortar mixture with a mobility of 5 cm or more are made in molds without a pallet.

The mold is placed on a brick covered with newsprint soaked in water or other non-glued paper. The size of the paper should be such that it covers the side faces of the brick. Before use, bricks must be rubbed by hand one against the other to eliminate sharp irregularities. Clay brick is used with a moisture content of no more than 2% and water absorption of 10-15% by weight. Bricks with traces of cement on the edges cannot be reused.

6.4.3. The molds are filled with a mortar mixture at a time with some excess and compacted by bayoning with a steel rod 25 times along a concentric circle from the center to the edges.

6.4.4. In winter masonry conditions, for testing solutions with antifreeze additives and without antifreeze additives, for each test period and each controlled area, six samples are made, three of which are tested within the time required for floor control of the strength of the solution after 3 hours of thawing at a temperature not lower than ( 20 ± 2) ° С, and the remaining samples are tested after thawing and subsequent 28-day hardening at a temperature not lower than (20 ± 2) ° С. The defrosting time must correspond to that indicated in table. 2.

table 2

6.4.5. Forms filled with a mortar mixture on hydraulic binders are kept before stripping in a normal storage chamber at a temperature of (20 ± 2) ° C and a relative air humidity of 95-100%, and forms filled with a mortar mixture on air binders are kept indoors at a temperature ( 20 ± 2) ° С and relative humidity (65 ± 10)%.

6.4.6. The samples are released from the molds in (24 ± 2) hours after placing the mortar mixture.

Samples made from mortar mixtures prepared on slag Portland cements, pozzolanic Portland cements with set retarders, as well as winter masonry samples stored in the open air, are released from the molds after 2-3 days.

6.4.7. After release from the molds, the samples should be stored at a temperature of (20 ± 2) ° C. In this case, the following conditions must be observed: samples from solutions prepared on hydraulic binders, during the first 3 days, must be stored in a normal storage chamber at a relative air humidity of 95-100%, and the remaining time before testing - in a room at a relative air humidity (65 ± 10)% (from solutions hardening in air) or in water (from solutions hardening in a humid environment); samples from solutions prepared with air binders should be stored indoors at a relative humidity of 65 ± 10%.

6.4.8. In the absence of a normal storage chamber, it is allowed to store samples prepared on hydraulic binders in wet sand or sawdust.

6.4.9. When stored indoors, samples should be protected from drafts, heating with heating devices, etc.

6.4.10 Before the compression test (for subsequent determination of density), the samples are weighed with an error of up to 0.1% and measured with a caliper with an error of up to 0.1 mm.

6.4.11. Samples stored in water should be removed from it no earlier than 10 minutes before testing and wiped off with a damp cloth.

Samples stored indoors should be cleaned with a hairbrush.

6.5. Testing

6.5.1. Before placing the sample on the press, the particles of the solution remaining from the previous test are carefully removed from the support plates of the press in contact with the edges of the sample.

6.5.2. The sample is installed on the bottom plate of the press centrally relative to its axis so that the base is the faces that are in contact with the walls of the mold during its manufacture.

6.5.3. The scale of the force meter of the testing machine or press is selected on the condition that the expected value of the breaking load should be in the range of 20-80% of the maximum load allowed by the selected scale.

The type (brand) of the testing machine (press) and the selected scale of the force meter are recorded in the test log.

6.5.4. The load on the specimen must increase continuously at a constant rate of (0.6 ± 0.4) MPa [(6 ± 4) kgf / cm 2] per second until its destruction.

The maximum force achieved during the test of the sample is taken as the value of the breaking load.

6.6. Processing of results

6.6.1. Compressive strength of the solution R calculated for each sample with an error of up to 0.01 MPa (0.1 kgf / cm 2) by the formula

A - working cross-sectional area of ​​the sample, cm 2.

6.6.2. The working cross-sectional area of ​​the samples is determined from the measurement results as the arithmetic mean of the areas of two opposite faces.

6.6.3. The compressive strength of the solution is calculated as the arithmetic mean of the test results of three samples.

6.6.4. The test results are entered in the journal in the form in accordance with Appendix 2.

7. DETERMINATION OF THE AVERAGE DENSITY OF THE SOLUTION

7.1. The density of the solution is determined by testing cubes with an edge of 70.7 mm, made from a mortar mixture of the working composition, or plates with a size of 50X50 mm taken from the seams of structures. The thickness of the plates should correspond to the thickness of the seam.

In production control, the density of solutions is determined by testing samples intended to determine the strength of a solution.

7.2. Samples are made and tested in batches. The batch shall consist of three samples.

7.3. Equipment, materials

7.3.1. To carry out the test, apply:

technical scales in accordance with GOST 24104;

drying cabinet in accordance with OST 16.0.801.397;

vernier caliper in accordance with GOST 166;

steel rulers in accordance with GOST 427;

desiccator according to GOST 25336;

anhydrous calcium chloride in accordance with GOST 450 or sulfuric acid with a density of 1.84 g / cm 3 in accordance with GOST 2184;

paraffin in accordance with GOST 23683.

7.4. Test preparation

7.4.1. The density of the solution is determined by testing samples in a state of natural moisture or normalized moisture state: dry, air-dry, normal, water-saturated.

7.4.2. When determining the density of a solution in a state of natural moisture, the samples are tested immediately after they are taken or stored in a vapor-tight package or sealed container, the volume of which exceeds the volume of the samples placed in it by no more than two times.

7.4.3. The density of the solution at the normalized moisture state is determined by testing the samples of the solution having the normalized moisture content or arbitrary moisture content with the subsequent recalculation of the results obtained to the normalized moisture content according to the formula (7).

7.4.4. When determining the density of a solution in a dry state, the samples are dried to constant weight in accordance with the requirements of clause 8.5.1.

7.4.5. When determining the density of a solution in an air-dry state, before testing, the samples are kept for at least 28 days in a room at a temperature of (25 ± 10) ° С and a relative humidity of (50 ± 20)%.

7.4.6. When determining the density of a solution under normal humidity conditions, the samples are stored for 28 days in a normal hardening chamber, desiccator or other sealed container at a relative humidity of at least 95% and a temperature of (20 ± 2) ° C.

7.4.7. When determining the density of a solution in a water-saturated state, the samples are saturated with water in accordance with the requirements of clause 9.4.

7.5. Testing

7.5.1. The volume of the samples is calculated by their geometric dimensions. The dimensions of the samples are determined with a caliper with an error of no more than 0.1 mm.

7.5.2. The mass of the samples is determined by weighing with an error of not more than 0.1%.

7.6. Processing of results

7.6.1. The density of the sample solution r w is calculated with an error of up to 1 kg / m 3 according to the formula

where T - sample weight, g;

V - sample volume, cm 3.

7.6.2. The density of the solution of a series of samples is calculated as the arithmetic mean of the test results of all samples of the series.

Note. If the determination of the density and strength of the solution is carried out by testing the same samples, then the samples rejected when determining the strength of the solution are not taken into account when determining its density.

7.6.3. The density of the solution at a normalized moisture state r n, kg / m 3, is calculated by the formula

, (7)

where r w is the density of the solution at humidity W m, kgf / m 3;

W n ¾ normalized moisture content of the solution,%;

W m ¾ the moisture content of the solution at the time of testing, determined in accordance with Sec. eight.

7.6.4. The test results must be entered in the log in the form in accordance with Appendix 2.

8. DETERMINATION OF THE MOISTURE OF THE SOLUTION

8.1. The moisture content of the solution is determined by testing samples or samples obtained by crushing samples after testing them for strength or extracted from finished products or structures.

8.2. The largest size of the crushed pieces of mortar should be no more than 5 mm.

8.3. Samples of samples are crushed and weighed immediately after sampling and stored in a vapor-tight package or sealed container, the volume of which does not exceed the volume of the samples placed in it by more than two times.

8.4. Apparatus and materials

8.4.1. The following are used for testing:

laboratory scales in accordance with GOST 24104;

drying cabinet in accordance with OST 16.0.801.397;

desiccator according to GOST 25336;

baking sheets;

calcium chloride according to GOST 450.

8.5. Testing

8.5.1. The prepared samples or samples are weighed and dried to constant weight at a temperature of (105 ± 5) ° С.

Gypsum solutions are dried at a temperature of 45-55 ° C.

The mass at which the results of two successive weighings differ by no more than 0.1% is considered constant. In this case, the time between weighings should be at least 4 hours.

8.5.2. Before re-weighing, the samples are cooled in a desiccator with anhydrous calcium chloride or together with an oven to room temperature.

8.5.3. Weighing is carried out with an error of up to 0.1 g.

8.6. Processing of results

8.6.1. The moisture content of the solution by weight W m as a percentage is calculated with an error of up to 0.1% according to the formula

(8)

where T v - mass of the solution sample before drying, g;

T With - mass of the solution sample after drying, g.

8.6.2. The moisture content of the solution by volume W o as a percentage is calculated with an error of up to 0.1% by the formula

where r about - the density of the dry solution, determined according to clause 7.6.1;

8.6.3. The moisture content of a solution of a series of samples is determined as the arithmetic mean of the results of determining the moisture content of individual solution samples.

8.6.4. The test results should be recorded in a logbook, which indicates:

place and time of sampling;

moisture state of the solution;

mortar age and test date;

sample labeling;

moisture content of the solution of samples (samples) and series by weight;

moisture content of the solution of samples (samples) and series by volume.

9. DETERMINATION OF WATER ABSORPTION OF SOLUTION

9.1. The water absorption of the solution is determined by testing the samples. The sizes and number of samples are taken in accordance with clause 7.1.

9.2. Apparatus and materials

9.2.1. The following are used for testing:

laboratory scales in accordance with GOST 24104;

drying cabinet in accordance with OST 16.0.801.397;

container for saturation of samples with water;

wire brush or abrasive stone.

9.3. Test preparation

9.3.1. The surface of the samples is cleaned of dust, dirt and traces of grease using a wire brush or an abrasive stone.

9.3.2. Samples are tested in a state of natural moisture or dried to constant weight.

9.4. Testing

9.4.1. The samples are placed in a container filled with water so that the water level in the container is about 50 mm higher than the upper level of the laid samples.

The samples are placed on spacers so that the height of the sample is minimized.

The water temperature in the container should be (20 ± 2) ° С.

9.4.2. The samples are weighed every 24 hours of water absorption on a conventional or hydrostatic balance with an error of not more than 0.1%.

When weighing on a conventional balance, samples taken out of water are preliminarily wiped with a wrung out damp cloth.

9.4.3. The test is carried out until the results of two successive weighings differ by no more than 0.1%.

9.4.4. Samples tested in the state of natural moisture, after the end of the water saturation process, are dried to constant weight according to clause 8.5.1.

9.5. Processing of results

9.5.1. Water absorption of a solution of a separate sample by weight W m as a percentage is determined with an error of up to 0.1% according to the formula

(10)

where T With - the mass of the dried sample, g;

m c is the mass of the water-saturated sample, g.

9.5.2. Water absorption of a solution of a separate sample by volume W o as a percentage is determined with an error of up to 0.1% by the formula

where r about - the density of the dry solution, kg / m 3;

r in - the density of water, taken equal to 1 g / cm 3.

9.5.3. The water absorption of a solution of a series of samples is determined as the arithmetic mean of the test results of individual samples in a series.

9.5.4. In the journal in which the test results are recorded, the following columns should be provided:

labeling of samples;

mortar age and test date;

water absorption of the sample solution;

water absorption of a solution of a batch of a sample.

10. DETERMINATION OF THE FROST RESISTANCE OF THE SOLUTION

10.1. The frost resistance of the mortar is determined only in the cases specified in the project.

Solutions of grades 4; 10 and solutions prepared with air binders are not tested for frost resistance.

10.2. The solution is tested for frost resistance by repeated alternate freezing of cubes with an edge of 70.7 mm in a state of saturation with water at a temperature of minus 15-20 ° C and thawing them in water at a temperature of 15-20 ° C.

10.3. To carry out the test, six sample cubes are prepared, of which three samples are frozen, and the remaining 3 samples are control samples.

10.4. The maximum number of cycles of alternating freezing and thawing, which the samples withstand during the test, are taken as the brand of the solution for frost resistance.

Frost resistance mortar grades should be adopted in accordance with the requirements of the current regulatory documentation.

10.5. Equipment

10.5.1. The following are used for testing:

freezing chamber with forced ventilation and automatic temperature control within minus 15-20 ° С;

a container for saturating the samples with water with a device that maintains the temperature of the water in the vessel within the range of plus 15-20 ° С;

molds for making samples in accordance with GOST 22685.

10.6. Test preparation

10.6.1. Samples to be tested for frost resistance (main) should be numbered, inspected and noticed defects (minor edges or corners, chipping, etc.) should be entered in the test log.

10.6.2. The main samples should be tested for frost resistance at 28 days of age after being kept in a normal hardening chamber.

10.6.3. Control samples intended for compression tests must be stored in a normal hardening chamber at a temperature of (20 ± 2) ° С and a relative humidity of at least 90%.

10.6.4. The main samples of the solution intended for testing for frost resistance and control samples intended for determining the compressive strength at 28 days of age, before testing, must be saturated with water without preliminary drying by keeping them for 48 hours in water at a temperature of 15-20 ° WITH. In this case, the sample should be surrounded on all sides by a layer of water with a thickness of at least 20 mm. The saturation time in water is included in the total age of the solution.

10.7. Testing

10.7.1. Primary samples saturated with water should be placed in a freezer in special containers or placed on mesh shelves. The distance between the samples, as well as between the samples and the walls of containers and the overlying shelves, must be at least 50 mm.

10.7.2. The samples should be frozen in a freezer that allows the chamber with the samples to be cooled and maintain a temperature of minus 15-20 ° C in it. The temperature should be measured at half the height of the chamber.

10.7.3. Samples should be loaded into the chamber after cooling the air in it to a temperature not higher than minus 15 ° С. If, after loading the chamber, the temperature in it turns out to be higher than minus 15 ° С, then the beginning of freezing should be considered the moment when the air temperature reaches minus 15 ° С.

10.7.4. The duration of one freezing should be at least 4 hours.

10.7.5. After unloading from the freezer, the samples should be thawed in a bath with water at a temperature of 15-20 ° C for 3 hours.

10.7.6. Control examination of samples should be carried out in order to terminate the frost resistance test of a series of samples in which the surface of two out of three samples has visible damage (delamination, through cracks, spalling).

10.7.7. After alternating freezing and thawing of the samples, the main samples shall be compression tested.

10.7.8. Compression specimens should be tested in accordance with the requirements of Sec. 6.

10.7.9. Prior to the compression test, the master specimens are examined and the area of ​​edge damage is determined.

If there are signs of damage to the support faces of the samples (peeling, etc.), before testing, they should be leveled with a layer of quick-hardening compound no more than 2 mm thick. In this case, the samples should be tested 48 hours after pouring, and for the first day the samples should be stored in a humid environment, and then in water at a temperature of 15-20 ° C.

10.7.10. Control samples should be tested for compression in a water-saturated state before freezing the main samples. The supporting surfaces of the specimens should be wiped off with a damp cloth before placing on the press.

10.7.11. When assessing frost resistance by weight loss after carrying out the required number of freezing and thawing cycles, the samples are weighed in a state saturated with water with an error of no more than 0.1%.

10.7.12. When assessing frost resistance by the degree of damage, the samples are examined every five cycles of alternating freezing and thawing. After thawing, the samples are examined every five cycles.

10.8. Processing of results

10.8.1. Frost resistance in terms of the loss of strength in compression of samples during alternating freezing and thawing is assessed by comparing the strength of the main and control samples in a state saturated with water.

The loss of strength of samples D in percent is calculated by the formula

(12)

where Rcounter- the arithmetic mean of the ultimate compressive strength of control samples, MPa (kgf / cm 2);

Rmain - the arithmetic mean of the ultimate compressive strength of the main samples after testing them for frost resistance, MPa (kgf / cm 2).

The permissible loss of strength of samples in compression after alternating freezing and thawing is no more than 25%.

10.8.2. Weight loss of specimens tested for frost resistance, M as a percentage, calculated by the formula

(13)

where m 1 - mass of a sample saturated with water before testing it for frost resistance, g;

m 2 - mass of a sample saturated with water after testing it for frost resistance, g.

The weight loss of the samples after the frost resistance test is calculated as the arithmetic mean of the test results of the three samples.

Allowed weight loss of samples after alternate freezing and thawing - no more than 5%.

10.8.3. The following data should be indicated in the frost resistance test log of samples:

type and composition of the solution, design grade for frost resistance;

marking, date of manufacture and date of testing;

dimensions and weight of each sample before and after testing and weight loss in percent;

hardening conditions;

a description of the defects found in the samples prior to testing;

description of external signs of destruction and damage after testing;

ultimate compressive strength of each of the main and control samples and the change in strength in percent after testing for frost resistance;

number of freeze and thaw cycles.

ANNEX 1

Mandatory

DETERMINATION OF THE COMPRESSION STRENGTH OF THE MORTAR TAKEN FROM THE SEAMS

1. The strength of the mortar is determined by testing the compression of cubes with ribs of 2-4 cm, made of two plates taken from horizontal joints of masonry or joints of large-panel structures.

2. Plates are made in the form of a square, the side of which must be 1.5 times the thickness of the plate, equal to the thickness of the seam.

3. Gluing plates of solution to obtain cubes with edges of 2-4 cm and leveling their surfaces is carried out using a thin layer of gypsum dough (1-2 mm).

4. It is allowed to cut out samples-cubes from plates in the case when the thickness of the plate ensures obtaining the required rib size.

5. Samples should be tested one day after their manufacture.

6. Sample cubes from a solution with edges 3-4 cm long are tested in accordance with clause 6.5 of this standard.

7. To test sample cubes from a solution with edges of 2 cm, as well as thawed solutions, a small-sized desktop press of the PS type is used. Normal load range is 1.0-5.0 kN (100-500 kgf).

8. The strength of the solution is calculated according to clause 6.6.1 of this standard. The strength of the solution shall be determined as the arithmetic mean of the test results of five samples.

9. To determine the strength of the solution in cubes with ribs of 7.07 cm, the test results of cubes of summer and winter solutions, hardened after thawing, should be multiplied by the coefficient given in the table.

GOST 5802-86 is intended to establish methods for determining the properties of mortars and mixtures prepared on mineral binders - cement, lime, gypsum, soluble glass, used in all types of construction, excluding hydraulic engineering. The standard does not apply to heat-resistant, chemically resistant and stressing solutions. GOST 5802-86 is valid from 01.07.86.

GOST 5802-86

Group W19

STATE STANDARD OF THE UNION OF SSR

CONSTRUCTION MORTARS

Test methods

Mortars. Test methods

Date of introduction 1986-07-01

* DEVELOPED by the Central Research Institute of Building Structures (TsNIISK named after Kucherenko) of the USSR State Construction Committee

* CONTRACTORS:

V.A. Kameiko, Cand. tech. Sciences (topic leader); I. T. Kotov, Cand. tech. sciences; N.I. Levin, Cand. tech. sciences; B.A. Novikov, Cand. tech. sciences; G.M. Kirpichenko, Cand. tech. sciences; V.S. Martynov; V.E.Budreyk; V.M.Kosarev, M.P. Zaitsev; N.S. Statkevich; E.B. Madorsky, Cand. tech. sciences; Yu.B. Volkov, Cand. tech. sciences; D.I.Prokofiev

* SUBMITTED by the Central Research Institute of Building Structures (TsNIISK named after Kucherenko) of the USSR State Construction Committee

_________________

* Information about developers and performers is given from the publication: USSR State Standard - Standards Publishing House, 1986. Note "CODE".

APPROVED AND PUT INTO EFFECT by the Decree of the State Committee of the USSR for Construction Affairs of December 11, 1985 N 214

REPUBLICATION. June 1992

This standard applies to mortar mixtures and building mortars made on mineral binders (cement, lime, gypsum, dissolving glass) used in all types of construction, except for hydraulic engineering.

The standard establishes methods for determining the following properties of a mortar mixture and mortar:

mobility, average density, delamination, water retention capacity, water separation of the mortar mixture;

The standard does not apply to solutions that are heat-resistant, chemically resistant and stressful.

1. GENERAL REQUIREMENTS

1.1. Determination of the mobility, density of the mortar and the compressive strength of the mortar is mandatory for all types of mortar. Other properties of mortar mixtures and mortar are determined in the cases provided for by the project or the rules for the production of work.

1.2. Samples for testing the mortar mixture and making samples are taken before the setting of the mortar mixture begins.

1.3. Samples should be taken from the mixer at the end of the mixing process, at the place of application of the solution from vehicles or a work box.

Samples are taken from at least three locations at different depths.

The sample volume must be at least 3 liters.

1.4. The taken sample must be additionally mixed for 30 s before testing.

1.5. The test of the mortar mixture should be started no later than 10 minutes after sampling.

1.6. The test of the hardened solutions is carried out on samples. The shape and dimensions of the samples, depending on the type of test, must correspond to those indicated in table. one.

1.7. The deviation of the dimensions of the molded samples along the length of the edges of the cubes, the sides of the cross-section of the prisms indicated in table. 1 should not exceed 0.7 mm.

Table 1

Note. During production control of solutions, which are simultaneously required for tensile bending and compressive strength, it is allowed to determine the compressive strength of the solution by testing the halves of prism specimens obtained after bending test of prism specimens in accordance with GOST 310.4-81.

1.8. Before forming the samples, the inner surfaces of the molds are coated with a thin layer of grease.

1.9. All samples must be labeled. The marking must be indelible and must not damage the specimen.

1.10. The manufactured samples are measured with a caliper with an error of up to 0.1 mm.

1.11. In winter conditions, for testing a solution with antifreeze additives and without them, sampling and making samples should be carried out at the place of its application or preparation, and storage of samples in the same temperature and humidity conditions in which the solution is placed in the structure.

Samples should be stored on the shelf of a lockable mesh-walled inventory box with a waterproof roof.

1.12. All measuring instruments and parameters of the vibrating platform should be checked within the time frames stipulated by the metrological services of the State Standard.

1.13. The temperature of the room in which the tests are carried out should be (20 ± 2) ° С, relative air humidity 50-70%.

The temperature and humidity of the room are measured with an MV-4 aspiration psychrometer.

1.14. For testing mortar mixtures and solutions, vessels, spoons, and other devices must be made of steel, glass or plastic.

The use of products made of aluminum or galvanized steel and wood is not allowed.

1.15. The compressive strength of the mortar taken from the seams of the masonry is determined according to the method described in Appendix 1.

The tensile strength of the solution in bending and compression is determined in accordance with GOST 310.4-81.

The tensile strength of the solution when splitting is determined according to GOST 10180-90.

The bond strength is determined according to GOST 24992-81.

Shrinkage deformation is determined according to GOST 24544-81.

Water separation of the mortar mixture is determined according to GOST 10181.0-81.

1.16. The results of tests of samples of mortar mixtures and samples of mortar are entered in the logbook, on the basis of which a document is drawn up characterizing the quality of the mortar.

2. DETERMINATION OF MOBILITY OF MORTAR MIXTURE

2.1. The mobility of the mortar mixture is characterized by the depth of immersion of the reference cone in it, measured in centimeters.

2.2. Equipment

2.2.1. The following are used for testing:

device for determining mobility (Fig. 1);

2.2.2. The reference cone of the instrument is made of sheet steel or plastic with a steel tip. The apex angle should be 30 ° ±.

The mass of the reference cone with the bar should be (300 ± 2) g.

Device for determining the mobility of a mortar mixture

7 - vessel for mortar mixture; 8 locking screw

2.3. Test preparation

2.3.1. All surfaces of the cone and vessel in contact with the mortar mixture should be cleaned of dirt and wiped with a damp cloth.

2.4. Testing

2.4.1. The amount of immersion of the cone is determined in the sequence shown below.

The device is installed on a horizontal surface and the freedom of sliding of the rod 4 in the guides 6 is checked.

2.4.2. The vessel 7 is filled with a mortar mixture 1 cm below its edges and compacted by bayoning with a steel rod 25 times and 5-6 times lightly tapping on the table, after which the vessel is placed on the device platform.

2.4.3. The tip of the cone 3 is brought into contact with the surface of the solution in the vessel, the rod of the cone is fixed with a locking screw 8 and the first reading on the scale is made. Then release the locking screw.

2.4.4. The cone should be immersed in the mortar mixture freely. The second reading is taken on the scale 1 min after the beginning of the immersion of the cone.

2.4.5. The immersion depth of the cone, measured with an error of up to 1 mm, is determined as the difference between the first and second readings.

2.5. Processing of results

2.5.1. The immersion depth of the cone is estimated from the results of two tests on different samples of the mortar mixture of the same batch as the arithmetic mean of them and rounded off.

2.5.2. The difference in the indices of individual tests should not exceed 20 mm. If the difference is more than 20 mm, then the tests should be repeated on a new sample of the mortar mixture.

2.5.3. The test results are entered in the journal in the form in accordance with Appendix 2.

3.DETERMINATION OF THE DENSITY OF THE MORTAR MIXTURE

3.1. The density of the mortar mixture is characterized by the ratio of the mass of the compacted mortar mixture to its volume and is expressed in g / cm3.

3.2. Equipment

3.2.1. The following are used for testing:

a steel cylindrical vessel with a capacity of 1000 ml (Fig. 2);

Steel cylindrical vessel

steel rod with a diameter of 12 mm, 300 mm long;

steel ruler 400 mm in accordance with GOST 427-75.

3.3. Test preparation and testing

3.3.1. Before the test, the vessel is preliminarily weighed with an error of up to 2 g. Then it is filled with an excess of the solution mixture.

3.3.2. The mortar mixture is compacted by bayonetting with a steel rod 25 times and 5-6 times lightly tapping on the table.

3.3.3. After compaction, the excess mortar mixture is cut off with a steel ruler. The surface is carefully leveled with the edges of the vessel. The walls of the measuring vessel are cleaned with a damp cloth from the solution that has fallen on them. Then weigh the vessel with the solution mixture to the nearest 2 g.

3.4. Processing of results

3.4.1. The density of the mortar mixture, g / cm, is calculated by the formula

where is the mass of a measuring vessel with a mortar mixture, g;

Measuring vessel weight without mixture, g.

3.4.2. The density of the solution mixture is determined as the arithmetic mean of the results of two determinations of the density of the mixture from one sample, differing from each other by no more than 5% from the lower value.

If there is a greater discrepancy in the results, the determination is repeated on a new sample of the solution mixture.

3.4.3. The test results must be entered in the log in the form in accordance with Appendix 2.

4. DETERMINATION OF SOLUTION MIXTURE

4.1. The delamination of the mortar mixture, which characterizes its cohesion under dynamic action, is determined by comparing the content of the aggregate mass in the lower and upper parts of a freshly formed sample with dimensions of 150x150x150 mm.

4.2. Equipment

4.2.1. The following are used for testing:

steel forms with dimensions of 150x150x150 mm in accordance with GOST 22685-89;

laboratory vibratory platform, type 435A;

laboratory scales in accordance with GOST 24104-88;

a sieve with a mesh of 0.14 mm;

baking sheet;

steel rod with a diameter of 12 mm, 300 mm long.

4.2.2. The laboratory vibrating platform in a loaded state should provide vertical vibrations with a frequency of 2900 ± 100 per minute and an amplitude of (0.5 ± 0.05) mm. The vibrating platform should have a device that, when vibrating, provides a rigid attachment of the mold with the solution to the table surface.

4.3. Testing

4.3.1. The mortar mixture is placed and compacted in a mold for control samples with dimensions of 150x150x150 mm. After that, the compacted mortar mixture in the mold is subjected to vibration on a laboratory vibrating platform for 1 min.

4.3.2. After vibration, the upper layer of the solution with a height of (7.5 ± 0.5) mm is taken from the mold onto a baking sheet, and the lower part of the sample is unloaded from the mold by tipping onto a second baking sheet.

4.3.3. The selected samples of the solution mixture are weighed with an error of up to 2 g and subjected to wet sieving on a sieve with holes of 0.14 mm.

With wet sieving, separate parts of the sample, laid on a sieve, are washed with a stream of clean water until the binder is completely removed. The rinsing of the mixture is considered complete when clean water flows out of the sieve.

4.3.4. The washed portions of the filler are transferred to a clean baking sheet, dried to constant weight at a temperature of 105-110 ° C and weighed with an error of up to 2 g.

4.4. Processing of results

where is the mass of the washed dried aggregate from the upper (lower) part of the sample, g;

The mass of the solution mixture taken from the upper (lower) part of the sample, g.

4.4.2. The delamination index of the mortar mixture in percent is determined by the formula

, (3)

where is the absolute value of the difference between the content of the filler in the upper and lower parts of the sample,%;

The total content of the filler of the upper and lower parts of the sample,%.

4.4.3. The stratification index for each sample of the solution mixture is determined twice and calculated with rounding to 1% as the arithmetic mean of the results of two determinations, differing from each other by no more than 20% from the lower value. If there is a greater discrepancy in the results, the determination is repeated on a new sample of the solution mixture.

4.4.4. The test results should be recorded in a logbook, which indicates:

date and time of testing;

place of sampling;

brand and type of solution;

results of private determinations;

arithmetic mean result.

5. DETERMINATION OF THE WATER-HOLDING CAPACITY OF THE SOLUTION MIXTURE

5.1. The water retention capacity is determined by testing a 12 mm thick layer of mortar laid on absorbent paper.

5.2. Apparatus and materials

5.2.1. The following are used for testing:

sheets of blotting paper 150x150 mm in size according to TU 13-7308001-758 - 88;

gauze pads measuring 250x350 mm in accordance with GOST 11109-90;

metal ring with an inner diameter of 100 mm, a height of 12 mm and a wall thickness of 5 mm;

a glass plate measuring 150x150 mm, 5 mm thick;

laboratory scales in accordance with GOST 24104-88;

a device for determining the water-holding capacity of a mortar mixture (Fig. 3).

5.3. Test preparation and testing

5.3.1. Before testing, 10 sheets of blotting paper are weighed with an error of up to 0.1 g, placed on a glass plate, a gauze cloth pad is placed on top, a metal ring is installed and weighed again.

5.3.2. The thoroughly mixed mortar mixture is placed flush with the edges of the metal ring, leveled, weighed and left for 10 minutes.

5.3.3. The metal ring with the solution is carefully removed along with the gauze.

The blotter paper is weighed with an error of up to 0.1 g.

Diagram of the device for determining the water-holding capacity of the mortar mixture

1 - a metal ring with a solution; 2 - 10 layers of blotting paper; 3 - glass plate; 4 - a layer of gauze fabric

5.4. Processing of results

5.4.1. The water-holding capacity of the mortar mixture is determined as a percentage of the water content in the sample before and after the experiment according to the formula

, (4)

where is the mass of blotting paper before testing, g;

Weight of blotting paper after testing, g;

Unit weight without mortar, g;

Unit weight with mortar, g.

5.4.2. The water-holding capacity of the solution mixture is determined twice for each sample of the solution mixture and is calculated as the arithmetic mean of the results of two determinations that differ from each other by no more than 20% from the lower value.

5.4.3. The test results should be recorded in a logbook, which indicates:

date and time of testing;

place of sampling;

brand and type of mortar mixture;

the results of particular definitions and the arithmetic mean.

6. DETERMINATION OF THE COMPRESSION STRENGTH OF A MORTAR

6.1. The compressive strength of the solution should be determined on cube samples with dimensions of 70.7x70.7x70.7 mm at the age established in the standard or technical conditions for this type of solution. Three samples are made for each test period.

6.2. Sampling and general technical requirements for the method for determining the compressive strength - according to paragraphs. 1.1-1.14 of this standard.

6.3. Equipment

6.3.1. The following are used for testing:

split steel molds with and without pallets in accordance with GOST 22685-89;

hydraulic press in accordance with GOST 28840-90;

calipers in accordance with GOST 166-89;

steel rod with a diameter of 12 mm, 300 mm long;

spatula (Fig. 4).

Spatula for compaction of mortar mixture

6.4. Test preparation

6.4.1. Samples from a mortar mixture with a mobility of up to 5 cm should be made in molds with a tray.

The mold is filled with a solution in two layers. Compaction of the layers of solution in each compartment of the mold is carried out by 12 presses of the spatula: 6 presses along one side, 6 - in the perpendicular direction.

The excess solution is cut flush with the edges of the mold with a steel ruler moistened with water and the surface is smoothed.

6.4.2. Samples from a mortar mixture with a mobility of 5 cm or more are made in molds without a pallet.

The mold is placed on a brick covered with newsprint soaked in water or other non-glued paper. The size of the paper should be such that it covers the side faces of the brick. Before use, bricks must be rubbed by hand one against the other to eliminate sharp irregularities. Clay brick is used with a moisture content of no more than 2% and water absorption of 10-15% by weight. Bricks with traces of cement on the edges cannot be reused.

6.4.3. The molds are filled with a mortar mixture at a time with some excess and compacted by bayoning with a steel rod 25 times along a concentric circle from the center to the edges.

6.4.4. Under the conditions of winter masonry, for testing solutions with antifreeze additives and without antifreeze additives, for each test period and each controlled area, 6 samples are made, three of which are tested within the time required for floor control of the strength of the solution after 3 hours of thawing at a temperature not lower than (20 ± 2) ° С, and the remaining three samples are tested after thawing and subsequent 28-day hardening at a temperature not lower than (20 ± 2) ° С.The thawing time should correspond to that indicated in table. 2.

table 2

6.4.5. Forms filled with a mortar mixture on hydraulic binders are kept before stripping in a normal storage chamber at a temperature of (20 ± 2) ° C and a relative air humidity of 95-100%, and forms filled with a mortar mixture on air binders are kept indoors at a temperature ( 20 ± 2) ° С and relative humidity (65 ± 10)%.

6.4.6. The samples are released from the molds in (24 ± 2) hours after placing the mortar mixture.

Samples made from mortar mixtures prepared on slag Portland cements, pozzolanic Portland cements with set retarders, as well as winter masonry samples stored in the open air, are released from the molds after 2-3 days.

6.4.7. After release from the molds, the samples should be stored at a temperature of (20 ± 2) ° C. In this case, the following conditions must be observed: samples from solutions prepared on hydraulic binders, during the first 3 days, must be stored in a normal storage chamber at a relative air humidity of 95-100%, and the remaining time before testing - in a room at a relative air humidity (65 ± 10)% (from solutions hardening in air) or in water (from solutions hardening in a humid environment); samples from solutions prepared with air binders should be stored indoors at a relative humidity of 65 ± 10%.

6.4.8. In the absence of a normal storage chamber, it is allowed to store samples prepared on hydraulic binders in wet sand or sawdust.

6.4.9. When stored indoors, samples should be protected from drafts, heating with heating devices, etc.

6.4.10. Before the compression test (for subsequent determination of density), the samples are weighed with an error of up to 0.1% and measured with a caliper with an error of up to 0.1 mm.

6.4.11. Samples stored in water should be removed from it no earlier than 10 minutes before testing and wiped off with a damp cloth.

Samples stored indoors should be cleaned with a hairbrush.

6.5. Testing

6.5.1. Before placing the sample on the press, the particles of the solution remaining from the previous test are carefully removed from the support plates of the press in contact with the edges of the sample.

6.5.2. The sample is installed on the bottom plate of the press centrally relative to its axis so that the base is the faces that are in contact with the walls of the mold during its manufacture.

6.5.3. The scale of the force meter of the testing machine or press is selected on the condition that the expected value of the breaking load should be in the range of 20-80% of the maximum load allowed by the selected scale.

The type (brand) of the testing machine (press) and the selected scale of the force meter are recorded in the test log.

6.5.4. The load on the specimen must increase continuously at a constant rate of (0.6 ± 0.4) MPa [(6 ± 4) kgf / cm] per second until its destruction.

The maximum force achieved during the test of the sample is taken as the value of the breaking load.

6.6. Processing of results

6.6.1. The compressive strength of the solution is calculated for each sample with an error of up to 0.01 MPa (0.1 kgf / cm) according to the formula

Working cross-sectional area of ​​the sample, see.

6.6.2. The working cross-sectional area of ​​the samples is determined from the measurement results as the arithmetic mean of the areas of two opposite faces.

6.6.3. The compressive strength of the solution is calculated as the arithmetic mean of the test results of three samples.

6.6.4. The test results are entered in the journal in the form in accordance with Appendix 2.

7. DETERMINATION OF THE AVERAGE DENSITY OF THE SOLUTION

7.1. The density of the solution is determined by testing cube samples with an edge of 70.7 mm, made from a mortar mixture of the working composition, or plates 50x50 mm in size, taken from the seams of structures. The thickness of the plates should correspond to the thickness of the seam.

In production control, the density of solutions is determined by testing samples intended to determine the strength of a solution.

7.2. Samples are made and tested in batches. The batch shall consist of three samples.

7.3. Equipment, materials

7.3.1. To carry out the test, apply:

technical scales in accordance with GOST 24104-88;

drying cabinet in accordance with OST 16.0.801.397-87;

vernier caliper in accordance with GOST 166-89;

steel rulers in accordance with GOST 427-75;

desiccator in accordance with GOST 25336-82;

anhydrous calcium chloride in accordance with GOST 450-77 or sulfuric acid with a density of 1.84 g / cm3 in accordance with GOST 2184-77;

paraffin in accordance with GOST 23683-89.

7.4. Test preparation

7.4.1. The density of the solution is determined by testing samples in a state of natural moisture or normalized moisture content: dry, air-dry, normal, water-saturated.

7.4.2. When determining the density of a solution in a state of natural moisture, the samples are tested immediately after they are taken or stored in a vapor-tight package or sealed container, the volume of which exceeds the volume of the samples placed in it by no more than 2 times.

7.4.3. The density of the solution at the normalized moisture state is determined by testing the samples of the solution having the normalized moisture content or arbitrary moisture content with the subsequent recalculation of the results obtained to the normalized moisture content according to the formula (7).

7.4.4. When determining the density of a solution in a dry state, the samples are dried to constant weight in accordance with the requirements of clause 8.5.1.

7.4.5. When determining the density of a solution in an air-dry state, before testing, the samples are kept for at least 28 days in a room at a temperature of (25 ± 10) ° С and a relative humidity of (50 ± 20)%.

7.4.6. When determining the density of a solution under normal humidity conditions, the samples are stored for 28 days in a normal hardening chamber, desiccator or other sealed container at a relative humidity of at least 95% and a temperature of (20 ± 2) ° С.

7.4.7. When determining the density of a solution in a water-saturated state, the samples are saturated with water in accordance with the requirements of clause 9.4.

7.5. Testing

7.5.1. The volume of the samples is calculated by their geometric dimensions. The dimensions of the samples are determined with a caliper with an error of no more than 0.1 mm.

7.5.2. The mass of the samples is determined by weighing with an error of not more than 0.1%.

7.6. Processing of results

7.6.1. The density of the solution sample is calculated with an error of up to 1 kg / m using the formula

, (6)

where is the mass of the sample, g;

Sample volume, cm.

7.6.2. The density of the solution of a series of samples is calculated as the arithmetic mean of the test results of all samples of the series.

Note. If the determination of the density and strength of the solution is carried out by testing the same samples, then the samples rejected when determining the strength of the solution are not taken into account when determining its density.

7.6.3. The density of the solution at a normalized moisture state, kg / m, is calculated by the formula

, (7)

where is the density of the solution at humidity, kgf / m;

Normalized moisture content of the solution,%;

The moisture content of the solution at the time of testing, determined in accordance with Sec. eight.

7.6.4. The test results must be entered in the log in the form in accordance with Appendix 2.

8. DETERMINATION OF THE MOISTURE OF THE SOLUTION

8.1. The moisture content of the solution is determined by testing samples or samples obtained by crushing samples after testing them for strength or extracted from finished products or structures.

8.2. The largest size of the crushed pieces of mortar should be no more than 5 mm.

8.3. Samples of samples are crushed and weighed immediately after sampling and stored in a vapor-tight package or sealed container, the volume of which does not exceed the volume of the samples placed in it by more than two times.

8.4. Apparatus and materials

8.4.1. The following are used for testing:

laboratory scales in accordance with GOST 24104-88;

drying cabinet in accordance with OST 16.0.801.397-87;

desiccator in accordance with GOST 25336-82;

baking sheets;

calcium chloride according to GOST 450-77.

8.5. Testing

8.5.1. The prepared samples or samples are weighed and dried to constant weight at a temperature of (105 ± 5) ° C.

Gypsum solutions are dried at a temperature of 45-55 ° C.

The mass at which the results of two successive weighings differ by no more than 0.1% is considered constant. In this case, the time between weighings should be at least 4 hours.

8.5.2. Before re-weighing, the samples are cooled in a desiccator with anhydrous calcium chloride or together with an oven to room temperature.

8.5.3. Weighing is carried out with an error of up to 0.1 g.

8.6. Processing of results

8.6.1. The moisture content of the solution by weight in percent is calculated with an error of up to 0.1% according to the formula

, (8)

where is the mass of the solution sample before drying, g;

Mass of the solution sample after drying, g.

8.6.2. The moisture content of the solution by volume in percent is calculated with an error of up to 0.1% according to the formula

where is the density of the dry solution, determined according to clause 7.6.1;

8.6.3. The moisture content of a solution of a series of samples is determined as the arithmetic mean of the results of determining the moisture content of individual solution samples.

8.6.4. The test results should be recorded in a logbook, which indicates:

place and time of sampling;

moisture state of the solution;

mortar age and test date;

sample labeling;

moisture content of the solution of samples (samples) and series by weight;

moisture content of the solution of samples (samples) and series by volume.

9. DETERMINATION OF WATER ABSORPTION OF SOLUTION

9.1. The water absorption of the solution is determined by testing the samples. The sizes and number of samples are taken in accordance with clause 7.1.

9.2. Apparatus and materials

9.2.1. The following are used for testing:

laboratory scales in accordance with GOST 24104-88;

drying cabinet in accordance with OST 16.0.801.397-87;

container for saturation of samples with water;

wire brush or abrasive stone.

9.3. Test preparation

9.3.1. The surface of the samples is cleaned of dust, dirt and traces of grease using a wire brush or an abrasive stone.

9.3.2. Samples are tested in a state of natural moisture or dried to constant weight.

9.4. Testing

9.4.1. The samples are placed in a container filled with water so that the water level in the container is about 50 mm higher than the upper level of the laid samples.

The samples are placed on spacers so that the height of the sample is minimized.

The water temperature in the container should be (20 ± 2) ° С.

9.4.2. The samples are weighed every 24 hours of water absorption on a conventional or hydrostatic balance with an error of not more than 0.1%.

When weighing on a conventional balance, samples taken out of water are preliminarily wiped with a wrung out damp cloth.

9.4.3. The test is carried out until the results of two successive weighings differ by no more than 0.1%.

9.4.4. Samples tested in the state of natural moisture, after the end of the water saturation process, are dried to constant weight according to clause 8.5.1.

9.5. Processing of results

9.5.1. The water absorption of a solution of a separate sample by weight in percent is determined with an error of up to 0.1% according to the formula

, (10)

where is the mass of the dried sample, g.

Weight of the water-saturated sample, g.

9.5.2. The water absorption of a solution of a separate sample by volume in percent is determined with an error of up to 0.1% according to the formula

where is the density of the dry solution, kg / m;

The density of water, taken equal to 1 g / cm.

9.5.3. The water absorption of a solution of a series of samples is determined as the arithmetic mean of the test results of individual samples in a series.

9.5.4. In the journal in which the test results are recorded, the following columns should be provided:

labeling of samples;

mortar age and test date;

water absorption of the sample solution;

water absorption of a solution of a batch of a sample.

10. DETERMINATION OF THE FROST RESISTANCE OF THE SOLUTION

10.1. The frost resistance of the mortar is determined only in the cases specified in the project.

Solutions of grades 4; 10 and solutions prepared with air binders are not tested for frost resistance.

10.2. The solution is tested for frost resistance by repeated alternate freezing of cube samples with an edge of 70.7 mm in a state of saturation with water at a temperature of minus 15-20 ° C and thawing them in water at a temperature of 15-20 ° C.

10.3. For testing, 6 sample cubes are prepared, of which 3 samples are subjected to freezing, and the remaining 3 samples are control samples.

10.4. The maximum number of cycles of alternating freezing and thawing, which the samples withstand during the test, are taken as the brand of the solution for frost resistance.

Frost resistance mortar grades should be adopted in accordance with the requirements of the current regulatory documentation.

10.5. Equipment

10.5.1. The following are used for testing:

freezing chamber with forced ventilation and automatic temperature control within minus 15-20 ° С;

a container for saturating the samples with water with a device that maintains the temperature of the water in the vessel within the range of plus 15-20 ° С;

molds for making samples in accordance with GOST 22685-89.

10.6. Test preparation

10.6.1. Samples to be tested for frost resistance (main) should be numbered, inspected and noticed defects (minor edges or corners, chipping, etc.) should be entered in the test log.

10.6.2. The main samples should be tested for frost resistance at 28 days of age after being kept in a normal hardening chamber.

10.6.3. Control samples intended for compression tests must be stored in a normal hardening chamber at a temperature of (20 ± 2) ° С and a relative humidity of at least 90%.

10.6.4. The main samples of the solution intended for testing for frost resistance and control samples intended for determining the compressive strength at 28 days of age, before testing, must be saturated with water without preliminary drying by keeping them for 48 hours in water at a temperature of 15-20 ° C. In this case, the sample must be surrounded on all sides by a layer of water with a thickness of at least 20 mm. The saturation time in water is included in the total age of the solution.

10.7. Testing

10.7.1. Primary samples saturated with water should be placed in a freezer in special containers or placed on mesh shelves. The distance between the samples, as well as between the samples and the walls of containers and the overlying shelves, must be at least 50 mm.

10.7.2. The samples should be frozen in a freezer, which provides the possibility of cooling the chamber with the samples and maintaining the temperature in it - 15-20 ° C. The temperature should be measured at the level of half the height of the chamber.

10.7.3. Samples should be loaded into the chamber after cooling the air in it to a temperature not higher than minus 15 ° C. If, after loading the chamber, the temperature in it turns out to be higher than minus 15 ° C, then the beginning of freezing should be considered the moment the air temperature reaches minus 15 ° C.

10.7.4. The duration of one freezing should be at least 4 hours.

10.7.5. After unloading from the freezer, the samples should be thawed in a bath with water at a temperature of 15-20 ° C for 3 hours.

10.7.6. Control examination of samples should be carried out in order to terminate the frost resistance test of a series of samples in which the surface of two out of three samples has visible damage (delamination, through cracks, spalling).

10.7.7. After alternating freezing and thawing of the samples, the main samples shall be compression tested.

10.7.8. Compression specimens should be tested in accordance with the requirements of Sec. 6 of this standard.

10.7.9. Prior to the compression test, the master specimens are examined and the area of ​​edge damage is determined.

If there are signs of damage to the support faces of the samples (peeling, etc.), before testing, they should be leveled with a layer of quick-hardening compound no more than 2 mm thick. In this case, the samples should be tested 48 hours after pouring, and the first day the samples should be stored in a humid environment, and then in water at a temperature of 15-20 ° C.

10.7.10. Control samples should be tested for compression in a water-saturated state before starting freezing of the main samples. The supporting surfaces of the specimens should be wiped off with a damp cloth before placing on the press.

10.7.11. When assessing frost resistance by weight loss after carrying out the required number of freezing and thawing cycles, the samples are weighed in a state saturated with water with an error of no more than 0.1%.

10.7.12. When assessing frost resistance by the degree of damage, the samples are examined every 5 cycles of alternating freezing and thawing. After thawing, the samples are examined every 5 cycles.

10.8. Processing of results

10.8.1. Frost resistance in terms of the loss of strength in compression of samples during alternating freezing and thawing is assessed by comparing the strength of the main and control samples in a state saturated with water.

The loss of strength of samples in percent is calculated by the formula

, (12)

where is the arithmetic mean of the ultimate compressive strength of control samples, MPa (kgf / cm);

The weight loss of the samples after the frost resistance test is calculated as the arithmetic mean of the test results of the three samples.

The permissible value of the weight loss of the samples after alternate freezing and thawing is no more than 5%.

10.8.3. The following data should be indicated in the frost resistance test log of samples:

type and composition of the solution, design grade for frost resistance;

marking, date of manufacture and date of testing;

dimensions and weight of each sample before and after testing and weight loss in percent;

hardening conditions;

a description of the defects found in the samples prior to testing;

description of external signs of destruction and damage after testing;

ultimate compressive strength of each of the main and control samples and the change in strength in percent after testing for frost resistance;

number of freeze and thaw cycles.

ANNEX 1

Mandatory

DETERMINATION OF THE COMPRESSION STRENGTH OF THE MORTAR TAKEN FROM THE SEAMS

1. The strength of the mortar is determined by testing the compression of cubes with ribs of 2-4 cm, made of two plates taken from horizontal joints of masonry or joints of large-panel structures.

2. Plates are made in the form of a square, the side of which must be 1.5 times the thickness of the plate, equal to the thickness of the seam.

3. Gluing plates of solution to obtain cubes with edges of 2-4 cm and leveling their surfaces is carried out using a thin layer of gypsum dough (1-2 mm).

4. It is allowed to cut out samples-cubes from plates in the case when the thickness of the plate ensures obtaining the required rib size.

5. Samples should be tested one day after their manufacture.

6. Sample cubes from a solution with edges 3-4 cm long are tested in accordance with clause 6.5 of this standard.

7. To test sample cubes from a solution with edges of 2 cm, as well as thawed solutions, a small-sized desktop press of the PS type is used. Normal load range is 1.0-5.0 kN (100-500 kgf).

8. The strength of the solution is calculated according to clause 6.6.1 of this standard. The strength of the solution shall be determined as the arithmetic mean of the test results of five samples.

9. To determine the strength of the solution in cubes with ribs of 7.07 cm, the test results of cubes of summer and winter solutions, hardened after thawing, should be multiplied by the coefficient given in the table.

APPENDIX 2

tests for determining the mobility, the average density of the mortar mixture and the compressive strength, the average density of the mortar samples

Laboratory manager _________________________________________________________

Responsible for manufacturing

and sample testing _____________________________________________________________

____________________

* The column "Notes" should indicate the defects of the samples: shells, foreign inclusions and their locations, the special nature of destruction, etc.

The text of the document is verified by:

official publication

Ministry of Construction of Russia -

Moscow: Standards Publishing House, 1992