TTK. Installation of reinforced concrete columns of industrial buildings and structures. Installation of steel columns Fastening of metal columns to reinforced concrete columns
Reinforced concrete columns one-story buildings are assembled entirely. Columns of great length, delivered to the construction site in separate parts, are preliminarily enlarged.
As a rule, reinforced concrete columns of one-story buildings are installed on glass-type foundations. Grouting with concrete or mortar (depending on the thickness of the layer) is performed in advance or immediately before the installation of the columns. The thickness of the layer is determined not only by the deviation from the design mark of the bottom of the glass, but also taking into account the length of the column intended for installation on this foundation, so that deviations in the length of the column from the design one can be extinguished by the thickness of this layer. The gravy made in advance, by the time the columns are installed, must have a strength of at least 50% of the branded one. For gravy, which is performed immediately before the installation of the columns, rigid mixtures are used, which are well compacted so that they are not squeezed out under the pressure of the supporting end of the column.
The preparation for the installation of columns includes the application of axial marks on four faces at the top and at the level of the top of the foundations. On columns intended for crane beams, in addition, on both sides of the consoles or traverses of two-branch columns, the risks of the axes of these beams are applied. On columns with a height of more than 12 m, clamps or clamps with two braces are fixed, with which these columns will be temporarily braced for adjacent foundations or special anchors in the plane of a row of columns.
In cases where the columns are not mounted from vehicles, they are preliminarily laid out at the installation sites. Columns can be laid out in different ways: depending on their weight, type, lifting capacity of erection cranes, as well as the number of columns that the crane mounts from one parking lot. When using self-propelled jib cranes, the columns are laid out as follows: the supporting end is closer to the foundation, and the head is directed into the span along the installation, providing that the place of the slinging of the column and the center of the support of the column and the foundation are on the same circle, described by a radius equal to the reach of the crane hook with installation site.
Installation is carried out by the "on weight" method. Slinging of columns is carried out with frame grips, and if there are through holes in the columns intended for slinging, with one- and two-pin grips with remote slinging.
Single-pin grips are made in the form of a U-shaped clip suspended from the slings, in the lower part of which there are holes with a pin entering them. When unslinging, the pin is pulled out of the hole in the column using a special rope.
If it is necessary to maintain the design scheme for supporting the column in the process of transferring it from a horizontal to a vertical position, it is necessary to rafter at two points. In this case, a two-pin balancing grip is used. It consists of a traverse with two blocks through which steel ropes are thrown with upper and lower frames with pins fixed on them. When unslinging the column, the upper pin is removed from the hole remotely, the pin of the lower frame is removed by the installer.
The crane lowers the column into the foundation glass, aligning the axial risks in the lower part of the column with the axial risks applied on the upper surface of the foundation. Then, with the help of two theodolites installed in the alignments of the longitudinal and transverse staking axes, the verticality of the installation of the column is checked, combining the position of the lower and upper notches on the column with the vertical sighting axis of the theodolite.
Wedges and inventory wedge inserts are used to temporarily fix the columns in the glasses of the foundations before they are monolithic with concrete. Wedges can be reinforced concrete, steel and wood. It is advisable to use reinforced concrete wedges, which, after embedding, remain in the concrete of the joint.
Wedges are made, depending on the depth of the foundation glass, 250-300 mm long with a bevel of one vertical edge by 1/10. When fixing the columns, one wedge is installed at each face with a width of up to 400 mm, and two at the faces of greater width.
When using wooden wedges, the columns are sealed in glasses with a concrete mixture in two stages: the first time to the level of the bottom of the wedges, the second time - after the concrete has hardened and the wedges have been removed.
For economic reasons, metal wedges are used in exceptional cases.
The inventory wedge insert holds the bottom of the column until the joint is sealed with concrete. It is very convenient to use. The principle of operation is the following. When the screw is rotated, the wedge moves in the body on a hinge, creating a spacer force between its outer face and the body of the liner.
Wedge inserts are installed in the gaps between the faces of the column and the walls of the foundation glass. Before sealing the joint with a concrete mixture, a fence is installed on the wedge liner, which is removed from the glass after the mixture has been compacted or after it has begun to set.
When installing columns with a height of more than 12 m, for additional temporary fixing of the column in the plane of the longitudinal axes of the building, it has to be unfastened with two braces. Inventory braces with a carabiner and a screw tie are well suited for this, which can be quickly installed and removed.
Conductors of various types are also used for temporary fixing of columns. The simplest consists of two parts connected by four tie bolts. Two parts of the conductor are installed on the surface of the foundation after the columns are installed in it and tightened with bolts. At the same time, the stable position of the column is ensured by the expansion of its base due to the conductor.
The position of the column relative to the center axes is straightened with the help of special jacks resting against the walls of the foundation glass.
In all cases, the columns must be installed and aligned so that the tolerances regulated by the SNiP or the project for the production of works are not exceeded.
Until the concrete of the column embedment reaches 70% of the design strength, the following structures cannot be installed on the columns, except for the design or assembly braces and spacers that ensure their stable position.
Reinforced concrete columns of rectangular or square section, with or without consoles, are mounted on one, two or more floors each separately, although in some cases columns with crossbars are pre-aggregated into flat frames or blocks, which is advisable with sufficient crane capacity.
These columns are mounted by the “on weight” method, slinging is performed in different ways.
As a rule, the lower columns are installed on glass-type foundations, aligned and fixed in them, like the columns of one-story buildings. And the columns of subsequent floors are already installed on the upper ends of the columns located below, or on crossbars.
The installation, alignment and temporary fixing of columns are practiced in the following three ways:
– installation according to risks with vertical alignment with a plumb line and welding of butt joint parts. To ensure the verticality of the columns during alignment, if necessary, braces are used. This method is used when installing columns with platform-type joints. It can also be used when mounting columns with milled steel plates at the ends, but then temporary fastening is performed with bolts, for which corners are welded to the embedded parts in advance;
- installation of columns on the heads of the columns, on which single conductors are fixed with screws in advance (the heads of the lower columns are usually 0.5-0.8 m above the floor level). The column installed in the conductor is fixed with adjusting screws and aligned along the center axes and vertically. Various designs of single conductors are used;
- installation of columns on the heads of the lower columns with temporary fixing and alignment with the help of group conductors for four columns. The group conductor is installed and fastened with clamps to the heads of the columns installed below. Each of the four columns is installed, fixed and aligned in the same way as installations with single conductors. Flooring with railings at the top of the conductor allows you to mount floor structures. After the installation work is completed and the elements are fixed in one cell of the building, the conductor is moved to the next
cell. The conductors are lifted to the next floor by a crane.
The most common group conductor is a frame-hinged indicator (RSHI). RSHI is a device consisting of spatial lattice scaffolds, on which there is a hinged (floating) frame with corner stops for fastening four columns at once in the upper position, retractable and rotary cradles for assemblers and welders. At the corners of the frame for temporary fastening of the columns in the design position, faceted corner clamps (stops) are installed - two swivel and two folding, which can occupy a transport or working position and do not interfere with the installation of crossbars and plates.
With the help of such a conductor, the columns are mounted without additional alignment. They are lifted one by one, brought by a crane to the corresponding clamps of the conductor and smoothly lowered onto the heads of the underlying columns. The side edges of the bottom of the mounted column are fixed with a tensioning device of the lower latch fixed to the column head, pulling it close to the sides of the latch. In this way, their exact alignment with the corresponding faces of the column head is ensured. The top of the column is fixed with an upper grip - indicator frame lock, bringing the column to a strictly vertical position.
The control of the position of mounted columns with a height of 2 floors of multi-storey buildings is checked on each floor.
Part 1
TYPICAL TECHNOLOGICAL CARD (TTK) FOR THE ORGANIZATION AND TECHNOLOGY OF INSTALLATIONBUILDINGSTRUCTURES
INSTALLATION OF REINFORCED CONCRETE COLUMNS
1 AREA OF USE
A typical flow chart has been developed for the installation of reinforced concrete columns.
General information
Installation of columns
Before installing the columns in the foundation sleeves, it is checked whether the position of the foundation corresponds to the design one, the risks of the installation axes are applied to the upper faces of the foundations and the side faces of the columns, and prefabricated elements, mounting equipment and tools are delivered to the installation area.
The following layouts of columns are used at the places of their installation: linear, ledges, inclined, centered.
With a linear layout (Fig. 1, A) columns are placed in one line parallel to the axis of movement of the crane. This scheme is used when the height of the column is less than the distance between the axes of the foundations. The trajectory of movement of the hook of the assembly crane in the plan with this layout of the columns consists of two arcs mutually opposite in the direction of rotation, which leads to an increase in the duration of the operation of the assembly crane.
Fig.1. Column layouts:
A- linear, b- ledges, V- inclined, G- centered;
1
- Column, 2
- foundation, 3
- the trajectory of the crane, 4
- parking of the assembly crane
When laying out with ledges (Fig. 1, b) columns are placed parallel to the axis of the building being mounted and the axis of the crane passage. This scheme is used when the length of the columns is more than the pitch of the columns. In contrast to the linear scheme, in this case, the assembly crane at each parking lot has a different outreach, which is inconvenient for the crane operator.
With an inclined scheme (Fig. 1, V) columns are laid out at an angle to the axis of the mounted row of structures and the axis of movement of the crane. Prefabricated elements according to this scheme are placed equally in relation to the foundations and crane parking places. It is expedient to use such a scheme when the size of the layout area is limited.
With a centered layout scheme (Fig. 1, G) the bottom of the column is located in the same alignment with the foundation in which it should be installed. From a horizontal to a vertical position, the columns are transferred by turning the crane boom towards the foundation. In this case, the supporting part of the mounted column will be in close proximity to the foundation.
Columns begin to mount after the acceptance of foundations or supports. At this stage, with the help of a theodolite, the position of the transverse and longitudinal axes of the foundations in the plan is checked, and with a level - the marks of the supporting surfaces of the foundations of the bottom of the glasses.
When preparing the column for installation, its dimensions are checked, and it is also determined whether there are any deviations, skew of the supporting surface relative to the plane perpendicular to the axis of the column, curvature of the surface of the side faces and ribs. Before lifting the column, the risks necessary to control its position in plan and in height are applied. Places of scratches: in the middle between two mutually perpendicular side faces at the level of the bottom and top of the column, on two side faces of the console along the axis of the crane beam, in the middle of the upper edge of the crane console. In the case when the columns are installed in glasses, the risks are applied at a height of 1.5-1.7 m above the level of the top of the foundation.
At the bottom of the glass foundations are laid reinforced concrete pads or a layer of hard concrete. The thickness of the linings or concrete layer is determined according to the executive scheme for the installation of foundations.
The columns are lifted in the plane of their greatest rigidity, therefore, if they were in the “flat” position before lifting, they are turned over to the “on edge” position. For this, apply U-shaped tilter. High columns are built with scaffolds and assembly ladders, which are used in the installation of crane beams and trusses. The columns are slinged with universal or traverse slings and semi-automatic grippers.
When installing columns, they are equipped with forked headband, which allows the use of cranes of lower capacity, as well as to reduce the swing of the column during its installation. For better guidance of columns to the installation site, manipulators are used (Fig. 2), fixed at the base of the boom. As rigging devices, a sling with a semi-automatic grip or equipped with a collapsible frame is used. 
Fig.2. Installation of columns with cranes equipped with:
A- fork headband, b- manipulator;
1
- tap, 2
- forked headband, 3
- Column, 4
- traverse, 5
- manipulator, 6
- foundation glass
The columns are aligned before the slings or grips are removed from them. The design marks of the supporting platforms of the columns in height are provided by installing reinforced concrete pads on the bottom of the foundation glass with dimensions in terms of 10x10, 15x20, 20x20 cm and a thickness of 20-30 mm. The use of such pads eliminates the need for a leveling layer of concrete or mortar. To temporarily fix the columns in the plan, use wedges, braces, struts, conductors. Columns up to 12 m high are fixed in the foundation glass with concrete, reinforced concrete, metal or wooden wedges at least 250 mm long, with a bevel of one side 1:10. In this case, after driving, the upper part of the wedge should protrude from the glass by about 100-110 mm. The number of wedges installed on each side of the glass depends on the section of the column and its mass; with a column edge width of up to 400 mm, one wedge is placed, and with a larger width, 2-3 wedges each. Wedges fasten columns of any section. However, they should not be used for straightening columns in the plan, since in this case the downtime of the assembly crane increases and the duration of the work of the assemblers decreases. The gap between the walls of the glass and the faces of the column is sealed with a concrete mixture.
After the concrete has gained the required strength (70% of the design), the wooden and metal wedges are removed, and the nests forming are sealed with mortar.
To fix the columns with inventory wedge inserts, the insert is inserted into the gap between the inner wall of the foundation cup and the edge of the column and is supported on the upper edge of the foundation. With the help of liners, the column can be displaced in plan by 50 mm during its installation in the foundation sleeve.
Installation of light columns is carried out in the following sequence. Mounting fixtures, tools, geodetic instruments and devices for safe work are placed within the installation zone. Prior to the installation, they check the position of the foundation glasses in terms of and in height, lay out the columns in the installation area, apply landmarks (Fig. 3) to the columns and foundations, prepare mechanisms, inventory and fixtures for work. 
Fig.3. Guidelines for the column:
A- on the foundation b- on a column; 1, 3 - risks, 2 - axes of installation of crane beams
Before lifting the column, check the reliability of its slinging (Fig. 4).
Fig.4. Column slinging scheme:
1 - universal rope sling for lifting the column, 2 - Column, 3 - wooden lining
After checking the reliability of the slinging, the column is installed by a link of four workers. Zvenevoy gives a signal to raise the column. At a height of 30-40 cm above the upper edge of the foundation, the installers guide the column into the glass, and the crane operator smoothly lowers it. At the same time, two installers hold the column, and the other two ensure alignment of the axial marks on the column and foundation in terms of.
To temporarily fix the column, wedge inserts are installed in pairs from two opposite sides in the gap between the column and the wall of the foundation glass.
The verticality of the installation of the column is checked using theodolites installed along the two axes of the column (Fig. 5).
Fig.5. Control of the vertical installation of the column:
1 - theodolite; pivot axes: 2 - on the foundation 3 - on a column
An important reserve for reducing the duration and complexity of the installation of columns is to reduce the duration of technological downtime of the crane by reducing the time for fixing the column. This is facilitated by the use of a jig with a clamping device (Fig. 6). Such a conductor on the foundation 1 fix with screws 2 . Then the risks on the frame 3 the conductor is combined with the center lines of the columns on the foundation, and the movable racks 9 with screws 8 brought to a vertical position. When lowering the column 6 into the conductor, with its weight, it unfolds the levers 4 and occupies a vertical position due to the fact that the pressure rollers 5 press it against the guide rollers 7 . Possible deviations in the dimensions of the column from the provided projects are compensated with the help of clamping-compensating devices.
Fig.6. Temporary fastening of the column by a jig of the TsNIIOMTP design with a clamping device:
column position: A- when lowering into the conductor; b- after lowering;
1
- foundation, 2
- screws, 3
- conductor frame, 4
- clamping levers, 5
- pinch rollers 6
- Column, 7
- guide rollers 8
- clamping screws 9
- movable stand 10
- lining
With the use of a conductor, columns with a section of 40x40, 40x50, 50x60 cm are mounted. After the joint concrete has gained 70% of the design strength, the conductor is removed and used to install other columns. Heavy columns of great length, in addition to wedges or wedge inserts, are reinforced with braces (Fig. 7) or rigid struts. They are installed in the plane of least rigidity.
Fig.7. Temporary fastening of columns with a height of more than 12 m with braces with a screw tie:
1 - foundation, 2 - Column, 3 - brace, 4 - a loop, 5 - wedge insert, 6 - slings
Installation using a single conductor
Tools, fixtures, equipment: a universal grip for mounting columns, an inventory handle for tightening the nuts of the clamping device, wedges for fastening columns (metal, concrete or hardwood) (16 pcs.), A box with hand tools, a blacksmith's sledgehammer (2 pcs. .), steel assembly scrap, a folding metal ruler, a single jig, jacks (2 pcs.), a metal brush.
Fig.8. Scheme of organization of the workplace during the installation of columns in the glasses of foundations:
1 - conductor trusses, 2 - jack, 3 - box with hand tools, 4 - single conductor (collapsible), 5 - theodolite, 6 - glass-type foundation, 7 - assembly scrap
Preparing the column for installation (Fig. 9)
Fig.9. Column slinging scheme:
1 - rigger, 2 - column, 3 - universal grip for mounting columns, 4 - pads
Rigger
1. Checks column markings.
2. Cleans the ends of the column from the influx of concrete and dirt with a metal brush.
3. Using a metal meter, divides one plane in width into two equal parts in two places (at the level of the top of the foundation and at the top of the column) and draws axial risks with a pencil.
4. Using similar techniques, he inflicts risks on the second plane perpendicular to the first.
5. Gives a signal to the crane operator to apply the universal gripper 3 to column 2.
6. Puts on the grip from the upper end of the column and, using the inventory handle, tightens the nuts of the clamping device.
7. Departs at a distance of 7 ... 8 m from the column.
8. Gives a signal to the crane driver to raise the column to a height of 200...300 mm.
9. Inspects fasteners.
10. Gives a signal to the crane operator to move the structure to the installation area.
Preparing the installation site
Installers 1st, 2nd
1. The 2nd installer lays out the tool, fixtures, inventory.
2. Then he checks the cleanliness of the foundation glass.
3. After checking the risks on the upper plane of the foundation glass.
4. The 1st and 2nd installers lay out the tools and fixtures according to the scheme for organizing the workplace.
5. The 1st installer installs and aligns two theodolites.
Reception, installation and fixing of the column (Fig. 10)
Fig.10. Scheme of fixing the column with wedges:
1 - foundation, 2 - wedges, 3 - 1st installer, 4 - mounted column, 5 - 2nd installer
Installers 1st, 2nd
1. The 1st and 2nd installers take the column at a height of 200...300 mm from foundation 1 and orient it in the right direction.
2. The 1st installer instructs the crane operator to lower column 4 into the foundation sleeve.
3. Installers hold the column while lowering.
4. Installers install wedges 2 between column 4 and sub-column 1 (four wedges on each side of the column).
5. With light blows of a sledgehammer, wedges are fixed.
Column alignment with wedges (Fig. 11)
Fig.11. Column alignment scheme with wedges:
1 - foundation, 2 - 1st installer, 3 - sledgehammer, 4 - 2nd installer, 5 - column, 6 - wedges
Installers 1st, 2nd
1. The 1st installer checks the relative position of the marks on the column and the foundation sleeve and gives a signal to the 2nd installer to move the bottom of the column in the required direction if necessary (if the marks do not match).
2. The 2nd installer, driving wedges 6, shifts the lower part of the column 5 to the design position.
3. Installers perform a similar operation with respect to the second axis.
4. The 1st installer guides the pipe axis of the first theodolite at risk at the bottom of the column and fixes the horizontal circle.
5. Then he transfers the theodolite tube to the risks in the upper part of the column.
6. If there are deviations, the 1st installer gives a signal to the 2nd installer to hammer in the wedges adjacent to the plane of the column and located on the side opposite to the deviation.
7. The 2nd installer drives the wedges to the required depth.
8. The 1st installer monitors the movement of the upper part of the column and gives a signal to finish driving.
9. By similar actions, the installers align the column with respect to the second axis.
Alignment of the column using a single conductor (Fig. 12)
Fig.12. Column alignment scheme:
1 - 1st installer, 2 - column, 3 - 2nd installer, 4 - jack, 5 - foundation
Installers 1st, 2nd
1. Installers install two jacks 4 on opposite sides of the column and rest their screws against the plane of the structure
2. The 1st installer checks the coincidence of the axial marks on the column and foundation sleeve 5 and gives a signal to move the bottom of the column in the desired direction.
3. The 2nd installer tightens the jack screw, which displaces the column, and loosens the screw at the second jack.
4. Having obtained a combination of marks, the installers rearrange the jacks to another axis of the column and, with similar movements, align the element relative to the second axis.
5. Installers take one conductor truss and install it on the foundation glass on both sides of the column.
6. Installers tighten the coupling bolts, connecting trusses.
7. The 1st installer gives a signal to the crane operator to loosen the slings.
8. Installers untie the column (see below).
9. The 1st installer guides the pipe axis of the first theodolite at risk at the bottom of the column and fixes the horizontal circle.
10. Then he moves the theodolite tube to the risk at the top of the column.
11. If there are deviations, the 1st installer gives a signal to the 2nd installer to move the top of the column.
12. The 2nd installer, by turning the screw of the corresponding support of the conductor, moves the top of the column in the desired direction.
13. Similarly, reconciliation is carried out in the other direction.
Column bridging (Fig. 13)
Fig.13. Scheme of slinging the column with jacks:
1 - column, 2 - clamping device screed, 3 - 2nd installer
Installers 1st, 2nd
1. The 1st installer gives a signal to the crane operator to loosen the slings.
2. The 2nd installer, using the inventory handle, unscrews the nuts of the two threaded ties of the clamping device 2.
3. The 1st installer removes the ties from the slats and gives the signal to the crane operator to raise the grapple.
Extraction of wedges
Installers 1st, 2nd
1. Installers with blows of a sledgehammer alternately shift the upper part of the wedges to one side and the other.
2. Remove the wedges.
Removing the conductor
Installers 1st, 2nd
1. Installers loosen tie bolts.
2. Installers remove the trusses and install them on the base.
Installation of a group conductor (Fig. 15)
Tools, fixtures, inventory: four-branch sling, semi-automatic grip, group conductor, scarpel, hammer, metal meter, steel brush, assembly crowbar, theodolite (2 pcs.).
Fig.14. Scheme of organization of the workplace during the installation of columns using a group conductor:
1 - installed column, 2 - clamps of the conductor, 3 - remote platforms of the conductor, 4 - theodolite, 5 - group conductor
Fig.15. Group conductor installation scheme:
1 - 2nd installer, 2 - group conductor, 3 - 1st installer, 4 - column heads
Installers 1st, 2nd, rigger
1. The rigger hooks a four-leg sling onto the crane hook. Gives a signal to give it to the standing group conductor.
2. Installers climb to the platform of the group conductor.
3. The 1st installer gives a signal to the crane driver to apply a sling to the conductor, together with the 2nd installer hooks the hooks of the slings into the lifting loops of the conductor.
4. At the signal of the 1st installer, the crane operator tightens the slings, and the installers check the correctness of the slinging.
5. The installers descend from the conductor's platform, move to a safe place.
6. The 1st installer allows the crane operator to lift and move the conductor to the installation site.
7. Installers take conductor 2 at a height of 300 mm above the level of column heads 4 and orient the conductor along the lower clamps located on the same vertical with the upper clamps.
8. The 1st installer gives the crane operator permission to smoothly lower the conductor and, together with the 2nd installer, holds it in such a way that the closed clamps are put on the column head.
9. The 2nd installer tightens the screws of the lower clamps - fastens the conductor to the column heads.
10. The 1st installer rises to the platform of the conductor, gives a signal to the crane operator to loosen the slings, removes them and holds them from swinging when lifting.
Preparing the column for installation (Fig. 16)
Rigger
1. Approaches the column 4 lying on the linings 5, inspects it, determines whether its position corresponds to the design one, detects contamination of its surface, concrete sagging.
2. With a scarpel and a hammer, it knocks down the influx of concrete, and with a metal brush it cleans off dirt, snow, ice.
3. Using a metal meter, divides two mutually perpendicular planes of the column at its base in half and inflicts axial risks. Similar risks are drawn on two planes in the upper part of the column. Gives a signal to the crane driver to apply it to the upper end of the lying column.
4. Removes a four-branch sling from the crane hook, hooks a semi-automatic gripper on the hook and gives a signal to the crane operator to apply it to the upper end of the lying column.
5. Brings the semi-automatic gripper 3 to the column and threads the steel pin 6 through the hole in the head of the column and jaws of the gripper.
6. Gives a signal to the crane operator to increase the grip tension.
7. After making sure that the slinging is reliable, he gives permission to move the column into the installation area.
Preparation of the column installation site
Installers 1st, 2nd
1. The 1st installer, using a metal meter, puts risks on the end of the column head, and then proceeds to prepare two theodolites.
2. The 2nd installer goes up to the platform of the conductor and prepares the clamps for the installation of the column.
Installation and alignment of the column (Fig.16-18)
Installers 1st, 2nd
1. The 2nd installer instructs the crane driver to bring the column to the conductor, takes it to a height of 200 ... 300 mm from the top of the conductor and leads it into the clamp (Fig. 17).
2. The 1st installer gives a signal to the crane operator to lower the column, accepts it, standing on the floor, and orients it to the end of the head of the downstream column 2.
3. The 2nd installer closes the bracket of the clamp 3 of the conductor with a lock (Fig. 18).
4. The 1st installer gives a signal to the crane driver to loosen the rope and, pulling out the pin 3 with the help of a cord, releases the grip 2 (Fig. 19).
5. Then allows the crane operator to remove the grip from the installed column.
6. Alignment of the column in the plan is performed by the 1st installer using an assembly crowbar, achieving alignment of the marks on the two planes of the joined columns.
7. After that, he directs the theodolite pipe at risk in the lower part of the column, fixes the horizontal circle of the instrument and transfers the pipe to the upper risk. If there is a deviation, he instructs the 2nd installer to move the upper part of the column in the desired direction with the clamp screws 4.
8. Having achieved the verticality of the column in one direction, the 1st installer proceeds to the second theodolite and, using similar methods, together with the 2nd installer, align the column in the other direction.
Installation of columns on the heads of lower columns using a single conductor
Tools, fixtures, inventory: universal load gripping device, universal rope sling for lifting columns, single conductor for mounting columns on the heads of underlying structures, steel assembly crowbar (2 pcs.), A box with hand tools, theodolite (2 pcs.), Metal brush , metal meter, pencil.
Fig.20. Scheme of the organization of the workplace when installing columns on the heads of the downstream using a single conductor:
1 - a single conductor at the previous parking lot, 2 - an installed column, 3 - the head of the underlying column, 4 - theodolite, 5 - mounting steel scrap, 6 - a box with hand tools
Preparation of the column and its supply to the installation area (Fig. 21)
Fig.21. Column slinging scheme:
1 - universal rope sling for lifting columns, 2 - slings of a universal load handling device, 3 - rigger, 4 - column, 5 - wooden lining
Rigger:
1. Examines the surface of the element to detect dirt and buildup of concrete.
2. Cleans the surface of the column with a metal brush.
3. Using a metal meter, divides the width of the plane of the column in half in the upper and lower parts of the column on two mutually perpendicular planes.
4. Apply axial risks with a pencil.
5. Puts on and fixes the universal mounting strap 1 on the column.
6. Gives a command to the crane operator to move the universal load handling device to the column.
7. Puts the rope sling 2 on the hook of the load handling device.
8. Gives a signal to the crane operator to tighten the slings.
9. Checks the reliability of the hold.
10. Departs from the column at a distance of 4 ... 5 m.
11. Gives a signal to the crane driver to raise the structure to a height of 200-300 mm from the storage level.
12. Repeatedly checks the reliability and correctness of the slinging.
13. Gives a signal to the crane operator to move the column to the installation area.
Preparation of the column installation site (Fig.22-24)
Installers 1st, 2nd
1. Installers lay out tools, fixtures and equipment according to the layout of the workplace.
2. The 1st installer divides the length of the side of the column head in half with a metal meter, and the 2nd installer applies axial risks with a pencil.
3. Installers do the same on the second, perpendicular to the first plane of the head.
4. The 1st installer gives a signal to the crane operator to bring the slings 3 to the conductor 1, installed on the second head (Fig. 22).
5. Installers put the hooks of the slings into the mounting loops of the conductor.
6. The 1st installer instructs the crane operator to tighten the slings.
7. After tensioning the lines, the installers loosen the screws securing the conductor and separate it into two parts (Fig. 23).
Fig.24. Assembly diagram of the conductor at the new parking lot:
1 - head of the downstream column, 2 - single conductor, 3 - 2nd installer, 4 - 1st installer
8. The 1st installer instructs the crane driver to lift the parts of the conductor and move them to the place of installation of the column.
9. Installers take the conductor at a height of 500 mm above the level of the head of column 1, put the conductor on it (Fig. 24).
10. Then, with the lower screws, the conductor is fixed to the underlying column.
11. The 1st installer gives the command to loosen the slings.
12. After loosening the slings, the installers remove the hooks of the sling from the conductor's mounting loops.
13. The 2nd installer installs and the 1st installer aligns two theodolites.
Installation and fixing of the column in the conductor (Fig. 25, 26)
Installers 1st, 2nd
1. The 1st installer gives a signal to the crane operator to move the column into the installation area.
2. Installers take column 3 at a height of 200 ... 300 mm above the level of the conductor 1 and orient to the head (Fig. 25).
3. The 1st installer instructs the crane operator to slowly lower the column.
4. Installers during lowering direct the column to the conductor.
5. After the contact of the supporting ends of the mounted column and the head, the installers fix the element in the jig using the upper screws.
6. Having fixed the column, the installers release the hooks of the universal load gripping device from the tension sling and remove it (Fig. 26).
Column alignment (Fig. 27)
Fig.27. Column alignment scheme in plan:
1 - assembly crowbar, 2 - 2nd installer, 3 - conductor, 4 - 1st installer
Installers 1st, 2nd
1. The 1st installer checks the coincidence of the marks on the head of the lower and the end of the upper columns.
2. At his command, the 2nd installer with a crowbar 1 moves the lower part of the mounted column until the marks on the same plane coincide completely.
3. The installers do the same on the second plane of the column, perpendicular to the first.
4. The 1st installer guides the pipe of the first theodolite to the lower line of the column and fixes the horizontal circle of the instrument.
5. Then he lifts the theodolite tube and directs it to the upper risk on the column.
6. Having detected the deviation of the marks, the 1st installer instructs the 2nd installer to move the column in the desired direction.
7. The 2nd installer first loosens the upper screws of the conductor on the side where the column is to be moved, and then tightens the screws on the opposite side.
8. Installers perform similar work by aligning the column with respect to the second axis.
2. ORGANIZATION AND TECHNOLOGY OF WORK PERFORMANCE
Reinforced concrete columns of one-story industrial buildings are installed in glass-type foundations, and multi-story buildings - on the ends of the columns of the lower floors.
Before starting the installation of the column, the marks of the axes of the column are applied to the upper surfaces of the foundations and the mark of the bottom of the glass is verified. For precise installation of the column, several methods are used: cement mortar is poured on the bottom of the glass in advance to the required mark, taking into account the length of the column; at the bottom of the glass in the poured solution along the jig, an imprint of the sole of the column is created with a stamp; a pin is installed and poured in the center of the column at the bottom of the glass, on which a hole is then placed in the sole of the column; asbestos-concrete gaskets of the required thickness are laid at the bottom of the glass.
The layout, lifting and installation of reinforced concrete columns is carried out in the same way as stable ones.
Columns with crane consoles are usually transported to the “flat” position, and due to the strength conditions when lifting columns of great height and for the convenience of slinging, in some cases they have to be turned to the “on edge” position, which requires the column to be tilted before lifting. To distribute the forces in the branches of the column, when lifting, a spacer jack is placed at the bottom of the support before lifting. Reinforced concrete columns are raftered in the same way as steel ones, above the center of gravity. If there are crane consoles, the slings are fixed under them. Slings must ensure the verticality of the column when it is installed in the design position, minimal labor intensity and safety of slinging. For slinging, a universal sling with a traverse and a collapsible frame is used, which is placed under the consoles. The pin that secures the joint of the frame can be pulled out with a thin cable or hemp rope tied to the end of the pin. At the same time, bridging does not require lifting onto the column. In some cases, a hole is provided at the bottom of the column, into which a shaft is inserted to secure the ends of the slings. Slinging is also possible with two universal (loop) slings, which are tightened on the column on a "boa constrictor", and they are held by friction. For safety, the slings are tied below the slinging loop of the column.
After fixing the column on the foundation, the hook is lowered and the loosened slings slide. When installing a column in a glass-type foundation, the axes of the raised column are combined with the axes of the marks on the surface of the glass, the verticality is verified and temporarily fixed in the glass, after which the strapping is performed.
For temporary fastening of the column, wedges, wooden, concrete and metal, wedge inventory liners, single and group conductors are used. The most commonly used wedges are wood and steel, it is advisable to use concrete wedges that do not need to be removed, but they are not widely used. Wedges with a column width of up to 500 mm are placed one per side, and with wider columns - two per side.
The cups are concreted in two steps: first to the bottom of the wedges so that they can be removed after the concrete reaches 25% strength, and then to the top. The alignment of the column should be carried out before bridging, until the column can be easily placed in the correct position. Columns above 12 m, in addition to fixing in a glass, should be moored along the row. Columns of multi-storey buildings are temporarily fixed in single or group conductors attached to the underlying structures. The columns are attached to the conductor with horizontal adjusting screws - stops, which can be used to align and fix the installed column (Fig. 28). Conductors are used for one, two and less often for four columns. The conductor for four columns allows for a non-alignment installation of the structure.
Fig.28. Spatial jig for four columns:
1 - Column; 2 - conductor; 3 - working floor; 4 - clamp with screws for alignment of columns; 5 - ways for the conductor; 6 - capture
The position of the columns is fixed by clamps located in two levels. Clamp screws ensure the vertical position of the columns. The presence of a flooring on the top of the conductor ensures the safety of the installation of crossbars (see Fig. 28).
Columns of multi-storey buildings can also be fixed with braces or struts with screw ties. In some cases, temporary fixing of the assembly joints of reinforced concrete columns is carried out by welding in the amount determined by the projects for the production of works. Such fastening increases the duration of the work of the erection crane, since slinging can be performed only after the end of temporary fastening by welding. The final fixing of the column joint is recommended after the installation and fixing of the crossbars and plates that unfasten it. The installation of structures on columns is allowed only after the design fixing of the column and the achievement of 70% of the strength of the monolithic concrete. Column installation work should be carried out in accordance with operational control charts.
3. REQUIREMENTS FOR THE QUALITY OF WORK PERFORMANCE
Deviations from the design position of the columns should not exceed the tolerances specified in Table 3.1.
Table 3.1
Limit deviations
|
Parameter |
Limit deviations, mm |
Control (method, volume, type of registration) |
|
Deviation of the axes of glass foundations from the center axes |
12 |
|
|
Deviation of the surface marks of the bottom of the foundation glass before laying the leveling layer |
-20 ±5 |
Measuring, each element, geodetic scheme |
|
Deviation of the marks of the element from the alignment marks of the column support |
8 |
Measuring, each element, geodetic scheme |
|
Deviation of the axes of the columns of one-story buildings in the upper section from the vertical with the length of the columns, m: |
|
|
|
up to 4 |
20 | |
|
4-8 |
25 | |
|
8-16 |
30 | |
|
16-25 |
40 | |
|
The same for multi-storey buildings, m: | ||
|
up to 4 |
12 |
Same |
|
4-8 |
15 | |
|
8-16 |
20 | |
|
16-25 |
25 | |
|
Difference in the marks of the tops of columns or support platforms with the length of the columns, m: | ||
|
up to 4 |
14 | |
|
4-8 |
16 | |
|
8-16 |
20 | |
|
16-25 |
24 | |
|
The difference in the marks of the tops of the columns of each tier of a multi-storey building, as well as the top of the wall panels at: |
Measuring, each element, geodetic executive scheme |
|
|
contact installation |
12+2p | |
|
installation by beacons |
10 |
ACT of acceptance of foundations (or supports) for the installation of columns (filling example).
ACT of inspection of hidden works installation of reinforced concrete columns and monolithic shoes (filling example).
4. MATERIAL AND TECHNICAL RESOURCES
Tools, fixtures, inventory:
universal load handling device,
universal rope sling for lifting columns,
a single conductor for mounting columns on the heads of underlying structures,
four-branch sling,
semi-automatic grip,
group conductor,
steel mounting scrap (2 pcs.),
hand tool box
theodolite (2 pcs.),
metal brush,
metal meter,
boaster,
hammer,
pencil.
5. ENVIRONMENT AND SAFETY REGULATIONS
INSTRUCTIONS
on labor protection and safety for the installer (installation of reinforced concrete structures)
I. General rules
1. Workers under the age of 18 who have been trained according to a standard program, verified by the administration in the knowledge of these instructions, and who have a written permission to perform work (permit) are allowed to install reinforced concrete structures.
2. It is allowed to work only where directed by the foreman or foreman.
3. Do not start work without receiving an introductory safety briefing and briefing on safe working practices at this workplace.
4. On the territory of the construction site, the following rules must be observed:
a) be attentive to the signals given by crane operators and drivers of moving vehicles, and follow them;
b) not be under the lifted load;
c) pass only in places intended for passage and indicated by signs;
d) do not cross the path in front of a moving vehicle;
e) do not go beyond the fences of hazardous areas;
f) places where work at height takes place, bypass at a safe distance, tk. possible accidental falling of objects from a height;
g) do not look at the flame of electric welding, because it can cause eye disease;
h) do not touch electrical equipment and el. wires (especially bare or broken), do not remove guards and protective covers from live parts of the equipment;
i) do not fix the malfunctions of the email. equipment, call an electrician;
j) not to work on mechanisms without undergoing special training and obtaining a permit;
k) in case of an accident, immediately seek medical help and at the same time inform the foreman (foreman) about the accident;
l) noticing a violation of the instructions by other workers or a danger to others, do not remain indifferent, but warn the worker and foreman about the need to comply with the requirements that ensure the safety of work.
II. Responsibilities before starting work
5. Check the serviceability and suitability of all rigging devices, make sure that the mounting crane is securely installed.
6. Prepare the mounting tool for work.
7. Inspect fences, scaffolding, scaffolding and make sure they are in good condition and stable.
8. Having found faults or defects in rigging devices (breakage of cable strands, bending, breakage of traverses, containers), mounting tools or fences, report this to the foreman and start work only with the permission of the foreman.
9. Check the sufficiency of workplace lighting.
10. In order to avoid electric shock, carefully inspect the nearby electrical wiring and, if bare, bare wires are found, report this to the master.
11. When working simultaneously at different levels along the same vertical, a continuous flooring or a continuous mesh should be made at each level to protect those working below from falling from above any objects or tools.
III. Requirements during work during the installation of reinforced concrete structures
12. Do not exceed the maximum lifting capacity of the crane at a given reach and do not exceed the maximum lifting capacity of rigging devices (slings, etc.).
13. The lifting of parts having a weight close to the limit should be done in two steps. First, raise the part to a height of 20-30 cm and in this position check the suspension and stability of the crane, and then lift the part to its full height.
14. Do not allow cargo to be pulled by a crane by oblique tension of the ropes or by turning the boom.
15. Moving people by crane is prohibited.
16. The lifting of small piece (brick, etc.), as well as bulk cargoes, should be carried out in special containers, which exclude the possibility of cargo falling out of the container.
17. In case of strong wind (more than 6 points), ice, heavy snowfall, rain and fog, installation work at height should be stopped.
18. Slinging of long elements should be carried out with at least two slings, and during installation, it is necessary to control the elements from a distance with rope extensions attached to both ends of the element being mounted.
19. Welding and embedding of units of installed reinforced concrete structures must be carried out from floors fenced at the workplace, mobile scaffolds with fenced platforms at the top or hanging cradles. The welder must have a bag for collecting cinders.
20. Reinforced concrete columns and frame racks must be equipped with mounting ladders or hanging cradles for subsequent installation work and release of slings, as well as for fixing or welding knots and installing crossbars.
21. For the transition of installers from one structure to another, assembly ladders, walkways and ladders should be used. Movement along the lower belt of a truss or beam is allowed only if there is a safety belt stretched along their rope to engage the carabiner. The rope must be pulled tight, sagging or loosening is not allowed.
22. Assembly and lifting of structures with a length of more than 6 m and a weight of more than 3 tons, requiring special care when moving and installing them, should be carried out under the direct supervision of a foreman or foreman.
23. For winding structures and installing them in place, it is necessary to use special crowbars or braces, and people are not allowed under the elements to be installed.
24. Blocks and hoists that are used for the installation of structures must be arranged so that the spontaneous fall of the cable or chain from the pulley, as well as their jamming between the block and the holder, is excluded.
25. Manual lifting winches should be equipped with an automatically operating brake or safety handles. During lifting, it is necessary to monitor the consistent and correct winding of the cable on the drum, avoiding winding above the side cheeks.
26. When working at height on riveting and welding without scaffolding, it is necessary to be tied to structures.
27. Separation of the raised structure from the lifting hook or braces should be carried out only after the structure has been placed on a sufficient number of bolts in accordance with the project for the production of works.
28. The installation of bolts should be done with assembly keys of the appropriate sizes. It is forbidden to place a gasket between the cheeks of the key and the nut, as well as to use keys with knocked down lips.
29. The slinging of the installed elements is allowed only after a strong and reliable fastening:
a) columns - anchor bolts or conductors and braces;
b) roof trusses - with braces, followed by connection with girders and connections with previously installed and fixed trusses;
c) crane beams and truss trusses - with bolts in an amount of at least 50% of the design amount;
d) elements with welded attachment according to the project - with temporary mounting bolts with full filling of all bolt holes.
IV. Requirements after work
30. Clean up the workplace.
31. Hand over all the tools in the pantry.
32. Report all noticed shortcomings to the foreman or foreman.
BASIC FIRE SAFETY INSTRUCTIONS
1. When performing construction and installation works, fire safety at the work site and at workplaces should be ensured in accordance with the requirements of the "Fire Safety Rules for the Production of Construction and Installation Works PPB-01-93 *", approved by the GUGPS of the Ministry of Internal Affairs of Russia.
________________
RD 34.03.307-87 is in force. - Database manufacturer's note.
2. Persons guilty of violating fire safety rules bear criminal, administrative, disciplinary or other liability in accordance with applicable law.
3. A person from among the engineering and technical personnel of the organization performing the work is appointed by order to be responsible for fire safety at a construction site.
4. All workers employed in production should be allowed to work only after passing fire-fighting briefing and additional training in preventing and extinguishing possible fires.
5. Signs should be posted at workplaces indicating the telephone number for calling the fire brigade and the scheme for evacuating people in case of fire.
6. Fire-fighting posts equipped with fire extinguishers, boxes with sand and shields with tools should be installed at the work site, warning posters should be posted. All inventory must be in good condition.
7. Campfires, open flames and smoking are prohibited on the territory.
8. Smoking is allowed only in places specially designated and equipped for this purpose. There must be a barrel of water.
9. The electrical network should always be kept in good condition. After work, it is necessary to turn off the electric switches of all installations and working lighting, leaving only the emergency lighting.
10. Work sites, workplaces and passages to them at night must be illuminated in accordance with GOST 12.1.046-85. Illumination should be uniform, without blinding effect of devices on workers. Work in unlit places is not allowed.
11. Workplaces and approaches to them must be kept clean, clearing them of debris in a timely manner.
12. Outdoor fire escapes and roof railings must be kept in good repair.
13. It is forbidden to clutter up driveways, passages, entrances to the locations of fire equipment, fire alarm gates.
14. Fire water supply networks must be in good condition and provide the required water flow for fire fighting needs according to the norms. Checking their performance should be carried out at least twice a year (in spring and autumn).
15. For heating mobile (inventory) buildings, factory-made steam and water heaters and electric heaters should be used.
16. Drying of clothes and shoes should be carried out in rooms specially adapted for this purpose with central water heating or using water heaters.
17. It is forbidden to dry cleaning materials and other materials on heaters. Oiled overalls and rags, containers from flammable substances must be stored in closed boxes and removed at the end of work.
18. It is forbidden to put on the base of the machine that has a leak of fuel or oil, and with an open neck of the fuel tank.
19. It is forbidden to store on the construction site stocks of fuel and oils, as well as containers from under them outside the fuel and oil storage facilities.
20. It is allowed to wash parts of machines and mechanisms with fuel only in rooms specially designed for this purpose.
21. Spilled fuel and oil must be covered with sand, which should then be cleaned up.
22. Electric welding installation must be grounded during operation.
23. Over portable and mobile electric welding installations used in the open air, sheds of non-combustible materials should be built to protect against precipitation.
24. Workers and engineers employed in production are obliged to:
Comply with fire safety requirements at work, as well as comply with and maintain a fire-fighting regime;
Take precautionary measures when using fire-hazardous substances, materials, equipment;
In the event of a fire, report it to the fire brigade and take measures to save people and extinguish the fire.
BIBLIOGRAPHY
SNiP 3.03.01-87. Bearing and enclosing structures.
SNiP 12-03-2001 Occupational safety in construction. Part 1. General requirements.
SNiP 12-04-2002. Labor safety in construction. Part 2. Construction production.
GOST 12.2.003-91. SSBT. Production equipment. General safety requirements.
GOST 12.3.009-76. SSBT. Loading and unloading works. General safety requirements.
GOST 12.3.033-84. SSBT. Construction vehicles. General safety requirements for operation.
GOST 24258-88. Scaffolding tools. General specifications.
PPB 01-03. Fire safety rules in the Russian Federation.
The electronic text of the document was prepared by CJSC "Kodeks"
and verified according to the author's material.
Author: Demyanov A.A. - Ph.D., teacher
Military Engineering and Technical University,
St. Petersburg, 2008
part 1
Installation of columns includes acceptance of foundations with geodetic verification of the position of their axes and elevations. At the same time, their dimensions, the position of embedded parts are checked. Axial risks are applied along four faces above and at the level of the top of the foundations, and on the columns intended for laying crane beams along them, risks are made on the consoles. On columns with a height of more than 12 m, clamps or clamps are fixed for their temporary fastening.
The columns are preliminarily laid out at the installation sites. When using self-propelled jib cranes, the columns are located with the supporting part closer to the foundation, the head is directed into the span during installation. Places for slinging columns must be available for work (Fig. 8.24, a, b).
The installation of columns is carried out by the "on weight" method. Slinging of columns is carried out with various friction grips or using self-balancing traverses (Fig. 8.24, c, d, e).
The columns lifted by the crane are lowered into the foundation glass, combining the axial risks in the lower part of the columns with the axial risks on the foundation. Then check the verticality of the columns using two theodolites.
When installing light and medium massive columns, single or group conductors can be used.
Columns 12 ... 18 m high are fixed in addition to the wedge liners with conductors or braces. Temporary fastening means are dismantled after final fixing and achievement by concrete of a joint of 70% R28 of durability.
The installation of the structures of each overlying floor of a multi-storey building should be carried out after the design fixing of all installation elements and the concrete of the monolithic joints of the strength specified in the PPR.
During the installation of columns, constant geodetic assurance of the accuracy of their installation should be carried out with the determination of the actual position of the columns to be mounted. The results of geodetic control should be documented as an executive scheme.
Rice. 4. Prefabricated foundations for individual supports: a and b - for brick pillars; wig - under a reinforced concrete column, 1 - pillow block, 2 - distribution block, 3 - brick pillar, 4 - reinforced concrete column, 5 - shoe, 6 - block glass, 7 - base plate
For columns of three- and four-story cutting (more than 10 m high), it is necessary to use devices that ensure the fastening of the columns not only in the glasses, but also in height, using struts, extensions, group conductors. When using single conductors, struts and guy wires, a differentiated or complex installation scheme can be adopted. 
Group conductors are used when mounting columns up to 18 m high. With a longitudinal arrangement of the crossbars, a set of three RSHIs is used, and with a transverse one, of two.
The mounted column is fed into the conductor and, with the help of clamping screws of the clamps, it is temporarily fixed and unslinged. The alignment of the column is carried out with the help of screws, and its verticality is checked with theodolites.
Ticket No. 22 Technique for the installation of prefabricated iron beams, trusses and roof slabs for one-story buildings.
Crane beams mounted after the concrete at the junction between the column and the walls of the foundation glass gains at least 70% of the design strength.
Crane beams are mounted in a separate stream or simultaneously with roof structures.
Prior to the start of installation, a geodetic check of the marks of the supporting platforms of the crane consoles of the columns is performed. Before lifting, fixtures and scaffolds are hung on the beam for its temporary fixing in the design position, as well as braces for its precise guidance. Beams are installed according to axial risks on them and crane consoles of columns with temporary fastening on anchor bolts and calibrated using special devices.
The axes of the crane beams are verified with a theodolite installed along the axis of the first crane beam on a special bracket attached to the first column so that the theodolite is located at a height of 500 mm above the upper plane of the beam. With a span of no more than 18 m, the axis of the crane beams is verified by measuring the span against each column with a tape measure. Crane beams and crane rails are leveled with a device installed in the middle of the span of the building at a height of 200 ... 300 mm from the surface of the beam.
After the final alignment of the crane beams, an executive diagram is drawn up, on which the marks of the top of the beams, deviations, and the design mark of the top of the beams are indicated. This scheme is used when installing rail tracks.
After alignment and geodetic verification of the correct installation of the beams, the embedded parts are welded.
Coating trusses usually mounted from vehicles. In some cases, as well as if it is necessary to enlarge the trusses at the installation site, they are placed in special cassettes in the span being mounted. At the same time, the trusses are laid out (Fig. 7) in such a way that the crane from each position can install the truss without a brace and, if possible, lay the coating slabs without moving.
Rafter trusses are usually mounted in the same stream as crane beams after installation of the beams. With one parking of the assembly crane.
Roof trusses and roof beams are mounted after installation and fixing of all underlying structures of the building frame. Before lifting, they are equipped with cradles and ladders, spacers for temporary fastening, a safety rope, braces and braces are fixed.
During installation, the truss is lifted, deployed by 90 ° using braces. Then they raise it to a height 0.5 ... 0.7 m higher than the level of the supports, and lower it onto the supports. The correct installation of beams and trusses is controlled by combining the corresponding risks. For slinging trusses, traverses with semi-automatic grippers are used, which provide remote slinging.
After lifting, installation and alignment, the first truss or beam is unfastened with braces, and the subsequent ones are fixed with special braces at the rate of at least two for trusses with a span of 24 ... 30 m. Braces and braces are removed only after installation and welding of the coating panels. To align and adjust the position on the support of beams or trusses, special conductors are used (Fig. 8).
Mounting plates carried out immediately after installation and permanent fixing on the supports of the next farm. This ensures the necessary rigidity of the next cell of the coating. With a lanternless roof, it is recommended to lay the coating slabs from one end of the truss to the other, starting from the side of the previously installed span, if there are lanterns, from the ends of the trusses to the middle of the span. The embedded parts of each slab at three support angles must be welded to the embedded parts of the upper chord of the truss.
Warehouse of plates is made in a zone of action of the assembly crane. The number of stacks of plates and their placement is determined from the condition of covering the cell between trusses from one crane stand.
In frame-panel buildings, the quality of installation of structures depends on the assembly of the frame. Therefore, it is important to prevent inaccuracies in the installation of columns, crossbars and other frame elements.
Installation of columns. Columns are mounted using group or individual conductors and gripping devices.
The columns of the first floor are installed in the glasses of the foundations in this sequence. According to the geodetic verification of the work performed, the risks of the axes of the columns are applied to the upper faces of the foundations. Axial risks are also marked on columns prepared for installation. Poured (if necessary) with concrete the bottom of the foundation glass to the design mark. They sling, lift and install the column, combining by weight the risks applied to it with axial risks. on the foundations. The column is aligned and temporarily fixed with the help of a conductor and portable jacks. The column is unslinged and after installing a number of columns in the same sequence, their position is finally checked, the columns are monolithic in the glasses with a concrete mixture.
To lift columns, friction grips, universal slings, semi-automatic and other grips are used.
When installing the column on the foundation (in a glass), before slinging, check the position of the column according to the installation risks and vertically, then temporarily fix it and only after that remove the slings from the column. Before the column is embedded in the foundation glass, it is finally verified: they make sure that the column is installed strictly vertically, and the risks applied to the installed column coincide with the risks on the foundation surface.
Methods of temporary fixing of the column depend on its type, mass and length.
Temporary fastening of columns up to 8-10 mm high, installed in foundation glasses, is carried out mainly with wooden, less often steel or reinforced concrete wedges. On each side, one wedge is placed in the gap between the column and the wall of the foundation glass. Hammer wooden or steel wedges with a metal sledgehammer. After driving, the wedge should be 12 cm higher than the edge of the foundation glass, so that it is easier to remove it after the final sealing of the column in the glass with concrete.
For temporary fixing and alignment along the axes of columns installed in a glass-type foundation, it is also recommended to use inventory rigid conductors.
Columns with a height of more than 10 m and a mass of more than 6 tons, for example, two-three-story columns of frame buildings, in addition to temporary fixing in the foundation glass with the help of wedges or a jig, are additionally fastened with rigid struts or flexible braces to the foundations of adjacent columns or to portable anchors.
The use of mobile or adjustable conductors, with the help of which columns are temporarily fixed on supports, significantly reduces the operating time of the erection crane with each column. After fixing the column in the conductor, it is unslinged and the crane can be used to mount other structures. At the same time, using simpler devices, it is possible to align and finally fix the installed columns. As a result of the use of such devices, the productivity of mounting mechanisms is increased, the duration and cost of mounting work are reduced.
Conductor for fixing the column
weighing up to 5 tons (218, a) consists of two fermo-
check 1 and tie bolts 2. The base of the opi truss
dig on the surface of the foundation (through screw
jacks 5) and after installation are pressed against the column
tie bolts.
The installation of the column using the conductor for its fastening and alignment is carried out in the following sequence. The column lifted by the crane is stopped at a height of 30-40 cm from the top of the foundation, turned to the design position and smoothly lowered into the glass. The base for the column (bottom of the glass) must first be calibrated with - taking into account the actual height of the column, so that after installation the mark of the top of it or the consoles is at the design level. When installing the column, the installers guide it in such a way that, if possible, immediately combine its installation axial risks with the risks on the foundation. If this cannot be done, then jacks 3 are lowered into the foundation glass and their screws are brought "to the stop in the faces of the columns. With the help of jacks (218, b), the column is pre-aligned, combining the position of the mounting marks on the column with the risks on the foundation in both directions. To do this, slightly loosen the screws of the jacks on one side of the column and move it with the screw of another jack.Then, on the top of the foundation glass from two opposite sides of the column, put the trusses 1 of the conductor, and fix it on the column with the help of tie bolts 2. The screws of the jacks 5 abut against the surface of the glass and after that, the slings are removed from it.
With the careful work of the installers and the crane operator, they quite accurately install the column with a crane into the foundation glass. However, this does not exclude the need for subsequent finishing of the column to the design position using a conductor and jacks. The final alignment of the position of the column in the plan is made by horizontal jacks 3.
The conductor for the vertical line (218, c) before about 8 tons is checked with a plumb line from the hand and straightened with jacks 5 of the conductor. When the screw of one or two support jacks is rotated on one side of the column, the corresponding truss of the conductor rises or falls and the column tilts somewhat; By manipulating the conductor's jacks in this way, the verticality of the column is achieved. After that, a geodetic check of the position of the mounted column in plan, height and vertical is carried out. If the accuracy of its installation is within the permissible range, the column is monolithic in the foundation glass. And after the concrete of the joint gains 70% of the design strength, the conductor and other temporary fasteners are removed and used when installing other structures. Columns are monolithic in groups of 6-10 columns on a grip equal to the replaceable installation volume.
The jig for fixing the column with a mass up to § t (219) provides a relatively greater stability of the column and can be used for installation. two-three-story columns - up to 10 m high. It is also used in the construction of one-story industrial buildings. The conductor consists of two trusses 1, welded from beams and corners, interconnected by four coupling bolts 2. The high location of the lower connecting corners of the conductor and the gap in the supporting channels allow you to install horizontal screw jacks on either side of the column and align it after - how it is temporarily fixed in the conductor.
Other types of conductors are also used, which can be installed after the column is loaded into the glass.
Columns of the second and next tiers in multi-storey buildings are mounted after instrumental verification of previously installed columns, crossbars and other structures. On the heads of the mounted columns, axial risks are applied, the heads are cleaned from concrete influxes, devices for temporary fastening of the installed columns are prepared and they are installed.
The jig for temporary fixing and alignment of single columns mounted on the heads of the columns protruding above the ceiling consists of four corner posts 1, a clamping clip and two adjusting devices - clips with adjusting screws. The clamping clip is located in the lower part and secures the conductor on the protruding head of the downstream column 2. The adjusting clips are located in the middle and upper parts of the racks. They consist of four beams 4 with adjusting screws 5, which ensure the movement of the installed column. Three beams have one screw each, and the fourth one has two, which makes it possible to rotate column 3 around the vertical axis (220).
Columns are mounted using a jig in the following order. The conductor is installed with racks in the girth of the head of the lower column and fixed on it with the coupling screws of the lower cage. The mounted column is brought in by a crane from above inside the conductor and installed on the head. Temporarily the column is fixed by screwing in the adjusting screws of the upper clips until they stop in the face of the column, after which it is released by the 6T hook of the mounting crane. For installation in the design position, the column is rotated and moved with the help of the upper and lower adjusting screws of the conductor. The alignment of the axial marks of the installed column and the previously installed one is achieved by the lower adjusting screws of the jig, and the vertical position of the column is achieved by the upper screws. After alignment and fixing of the column by welding the embedded parts or outlets of the reinforcement, the clamping screws are loosened and the conductor is removed.
The columns of the second and next tiers in multi-storey buildings are also fixed, depending on the design of the frame, with struts, ties or group conductors.
When supporting columns at the floor level, rigid struts and flexible braces are used. Flexible connections (221, a) consist of an inventory "cage 2, hinged rods 5 made of reinforcing steel and turnbuckles 4, with which the tension of the bonds and the position of the column 1 are changed during alignment. Rigid struts (221.6) consist of a cage 2 , struts 7 from pipes with turnbuckles 4.
When mounting columns of multi-storey buildings, group conductors for four columns are increasingly used, designed to temporarily fix and correct their position during alignment, for example, a frame-hinged indicator (RSHI), developed at the suggestion of eng. Y. S. Deycha.
The frame-hinged indicator (RSHI) provides temporary fixing and the specified accuracy of the installation of columns by forced receptions. It consists of a floating articulated-indicator frame 11 (222, a) with swivel 2 and folding 7 clamps mounted on it for temporary fixing of the installed columns /. Longitudinal 4 and transverse 5 rods with locks provide fixation of the mutual position of the frame-hinge indicators in the plan. Spatial scaffolding 12, the conductor rests on the ceiling or on the upper edges of the foundations (when installing the columns of the first tier). The floating frame is the main working body of the RSHI. It allows you to install RSHI with a deviation in plan by 100-200 mm from the design position, followed by alignment and precise fixation of only the indicator frame itself.
When mounting the frame (222.6), first install the first set of RSHI-I, fix it and align it along alignments A and B, then install RSHI-P and align it along alignment B. In the other alignment, the position of RSHI-P in the plan is not verified, and it is fixed by rods 5 connected to the already calibrated RSHI-I. Next, RSHI-Sh is installed, aligned along alignment A and the position in alignment B is fixed with rods 4 connected to RSHI-I. The position of RSHI-IV is fixed by automatic connection of rods 4 and 5 to the previously adjusted RSHI-P and RSHI-Sh.
After installing, fixing and aligning the RSHI sets, columns are mounted, the position of which in the plan and vertically is fixed with a given accuracy by rotary and folding collars of the floating frame.
RSHI are rearranged only after the final processing of the butt joints of the columns, installation and fixing of Other prefabricated structures that ensure the stability of the frame. For the convenience of the installers, rotary cradles are mounted on the RSHI spatial scaffolds, from which the frame joints are processed.
Installation of crossbars. The frame crossbars are mounted after the columns are fixed in the design position. The crossbar is slinged for mounting loops and fed to the installation site. The designs of the junction of crossbars with columns in frame multi-storey buildings are different depending on the design solution. However, in all cases, the crossbars are attached to the columns by welding the embedded parts or by embedding the reinforcement outlets from the head of the lower column and the reinforcing outlets of the crossbar.
Having lowered the crossbar 3 (223) on the support platforms [(console) of the column /, they check the compliance with the design of the width of the supports, the coincidence of its marks 7 with the axial risks of the column 4 and attach the crossbar with an electric tack to the embedded parts 6 of the columns. The joints of the crossbars with other elements are sealed after the final alignment of the frame of the mounted cell. When aligning structures with a template or steel tape measure, the position of the crossbar in the plan is controlled, and with the help of a level or water level, the mark of the top of the crossbar and its horizontalness are checked. Installation of crossbars is carried out from inventory tables or scaffolds.
Installation of panels and decking. Panels
or floor decking during installation is temporarily not
fasten. They are installed in the usual way,
slinging for mounting loops or technological
holes. For permanent fixing of floor slabs
their embedded parts are welded to the embedded parts
crossbars or load-bearing walls. This fastening is performed
before the installation of overlying structures and only
after being verified and finalized
crossbars. The seams between the floor slabs are frame-pa-
residential buildings close up in accordance with the instructions
mi of the project with a solution or with the installation of fittings and
pouring concrete.
The installation of glass-type foundations and, in general, the construction of structures of the underground part of the building are classified as zero-cycle works and are carried out by an independent assembly stream. The above-ground part of the building is usually mounted by a mixed method, when columns are mounted by independent flows and wall panels are hung, and installation of crane, under-rafter and truss trusses is carried out in a complex, and covering panels are laid.
For one-story industrial buildings, a range of prefabricated reinforced concrete columns up to 19.35 m high and weighing up to 26.4 tons, mounted in glass-type foundations, has been developed.
Before installing columns, you must:
- - fill the sinuses of the foundations;
- - put on four faces at the level of the upper plane of the foundations the risks of the installation axes;
- - close the glasses of the foundations with shields to protect them from pollution;
- - arrange roads for the passage of the assembly crane and cars;
- - prepare sites for storing columns at the place of their installation;
- - deliver to the installation area the necessary installation tools, fixtures and tools;
- - check the position of all embedded parts of the columns;
- - apply the risks of the installation axes on the side faces of the columns.
The columns are preliminarily laid out at the installation sites on wooden linings with a thickness of at least 25 mm. The layout of the columns is carried out in such a way that the crane from the assembly site can install them in the design position without changing the boom reach. Before installation, each column must be inspected so that it does not have deformations, damage, cracks, shells, chips, exposed reinforcement, concrete sagging. It is necessary to check the geometric dimensions of the column, the presence of a mounting hole, the correct installation of steel embedded parts.
Before or simultaneously with slinging, a column with a height of more than 12 m is built up with stairs, hinged cradles, braces.
Slinging columns carried out for the mounting loops, for the mounting rod, passed into a special hole in the column. Friction grips or various self-balancing traverses are widely used, allowing the column to be lowered vertically onto the foundation. All of them must provide remote slinging, eliminating the need for a worker to rise to the slinging site after installing the column in the foundation sleeve. The columns are lowered into the foundation glass with the help of a mounting crane on reinforced concrete pads or on a leveling layer of concrete mix.
Alignment and temporary fixing columns installed in the foundations are carried out using a set of mounting equipment. The design position of the bottom of the column at the bottom of the foundation glass, temporary fastening and vertical alignment of the columns are carried out using wedge liners. The stability of the columns after installation is provided with temporary fasteners, most often with conductors or wedge liners. Vertical alignment and correction of columns is carried out using jacks; in this case, the deviation from the vertical and the displacement of the axes of the columns in the lower section should not exceed the standard values.
Columns up to 12 m high are usually fixed in foundation glasses only with the help of wedge liners; for higher columns, conductors and braces are additionally used. The slinging of the installed columns should be carried out after they are securely fixed in the foundation glasses with wedge liners, and, if necessary, with braces.
The inventory wedge insert consists of a body with a nut and a handle, a screw with a boss and a wedge suspended on a hinge. Wedge inserts are installed in the gaps between the faces of the column and the walls of the foundation glass. For gaps greater than 90 mm, additional inserts are used. When the screw is rotated with a key, under the action of the boss, the wedge moves in the body on a hinge, as a result, a spreading force is created between the wedge and the body of the glass. Before sealing the joint between the column and the foundation with a concrete mixture, a fence is installed on the wedge liner, which is removed from the glass immediately after compaction of the rigid concrete mixture or after the start of setting with ordinary mixtures.
Conductors of various types are used for temporary fixing of columns. The conditions for the use of various types of conductors, the procedure for performing work on the installation and alignment of columns with their use is specified in the project for the production of works.
After the alignment of the columns, their fixing in the design position is carried out by concreting the joints with a concrete mix on quick-hardening non-shrinking cement using a pneumatic blower. The wedge inserts are removed only after the concrete has acquired the joint strength specified in the project for the production of works or when the concrete reaches 50% of the design strength.
When installing columns, it is necessary to check the level of the bottom of the foundation glass, the alignment of the risks on the edge in the lower part of the column with the alignment risk on the upper edge of the foundation, the verticality of the columns, the marks of the crane console and the head of the column. The alignment of the axes of the column and the staking axes must be controlled along two axes, the verticality of the column must be ensured using one or two theodolites along the two staking axes or a zenith device using the vertical design method. Elevations of support platforms for crane beams and trusses are controlled by the method of geometric leveling.
Installation of columns
Metal columns installed on solid concrete foundations can be supported:
- - on anchor bolts pre-embedded in foundations with grout at the joints of the cement mortar after alignment of the installed column along two mutually perpendicular axes;
- - directly on the surface of foundations erected to the design mark of the milled column foot without subsequent grouting with cement mortar;
- - on pre-installed, calibrated (with a layer of cement mortar, if necessary) steel base plates with a planed top surface (non-alignment installation).
When preparing columns for installation, the following risks are applied to them: the longitudinal axis of the column at the level of the bottom of the column and the top of the foundation.
Columns installed on foundations are provided only with anchor bolts if the column has wide shoes and at a height of up to 10 m. Higher columns with narrow shoes, in addition to bolting, are moored in the plane of least rigidity on both sides. The braces are fixed on the upper part of the column before it is lifted and, during installation, they are fastened to anchors or adjacent foundations. After tensioning the braces, the slings can be removed from the column.
It is possible to remove the braces only after fixing the columns with permanent elements. The stability of the columns in the direction of the axis of the building is provided by crane beams and connections installed after the installation of the first pair of columns and the crane beam connecting them.
Metal columns installed on foundations are fixed during installation with anchor bolts. If metal spacers are placed under the base of the column, they must be welded. The columns of the upper tiers (for example, in a built-in whatnot) are fastened with high-strength bolts or welded.
Alignment of frame structures, especially columns, requires a lot of labor. Application alignment-free mounting method allows to improve the quality of work while reducing the construction time of the structure.
For alignment-free installation, appropriate preparation of structures at the manufacturing plant and at the construction site is necessary. Increased accuracy of manufacturing structures is provided by the following:
- - structures of the shoe of the columns and the base plate of the shoe are manufactured and delivered to the facility separately;
- - the ends of the two branches of the columns must be milled;
- - base plates are made planed.
4 strips with threaded holes must be welded to each base plate for the installation of bolts; on the branches of the columns, axial risks should be applied.
With a non-aligned mounting method, the steel columns rest on a steel plate. In this case, the surface of the foundations is concreted below the design mark by 50 ... 60 mm, and after the precise installation of the slab, it is poured with cement mortar. The base plate is installed with adjusting bolts on the support strips, which must be concreted into the foundation flush with its surface as embedded parts. The reference plane of the plate is set by adjusting the nuts of the set screws along the level. The value of the actual mark of the base plate should not differ from the design by more than 1.5 mm.
When installing the column, the axial risks on its branches are combined with the risks applied on the base plates, which ensures the design position of the column, and it can be fixed with anchor bolts. Additional displacement of the column for alignment along the axes and height is not required in this case. After installing the braces to the mounted structures of the columns and their tension, they begin to mount the crane beams. Crane beams installed according to axial risks do not require additional alignment. After fixing them on the bolts, the braces are removed.
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