Construction technology of large steel structure workshop

Abstract

The invention discloses a large-scale steel structure factory building construction process, comprising the following steps: step 1, assembling wall steel structure panels according to relevant design requirements, then installing steel columns as the column point support structure of the grid and the support structure of the entire steel structure factory building according to the designed position, and setting a grid support on the top of the steel column; step 2, assembling the grid structure unit and hoisting it to the grid support for installation, the grid is a square tetrahedral pyramid bolt ball flat grid; step 3, building a roof panel layer on the assembled grid, and installing the wall steel structure panel to complete the construction of the steel structure factory building. The invention can achieve safe, efficient and high-quality construction on the basis of meeting relevant construction standards and specifications.

Description

Technical Field

[0001] The present invention relates to the technical field of building construction, and more specifically, to a construction process for a large steel structure factory building. Background Art

[0002] Steel structure factories are widely favored because of their fast construction speed, light weight, strong bearing capacity, good seismic performance, small structural space area, economy and environmental protection. Nowadays, they have gradually replaced the traditional bulky reinforced concrete structures in the design of industrial factories and are widely used, and they occupy an important position in construction projects.

[0003] In order to fully guarantee the construction quality and improve the construction progress safely and effectively, the relevant construction standards and specifications must be strictly followed during the entire installation process. Under the restrictions of relevant construction standards and specifications, how to achieve safe, efficient and high-quality construction is what we need to focus on in this application project. Summary of the invention

[0004] An object of the present invention is to provide a large-scale steel structure factory building construction process, which can achieve safe, efficient and high-quality construction on the basis of meeting relevant construction standards and specifications.

[0005] In order to achieve these purposes and other advantages according to the present invention, a large-scale steel structure factory building construction process is provided, comprising the following steps:

[0006] Step 1: Assemble the wall steel structure panels according to the relevant design requirements, and then install the steel columns as the column point support structure of the grid and the support structure of the entire steel structure workshop according to the designed position, and set the grid support on the top of the steel column;

[0007] Step 2: Assemble the grid structure unit and hoist it onto the grid support for installation. The grid is a square pyramid bolt ball flat grid;

[0008] Step 3: Build the roof panel layer on the assembled grid, and install the wall steel structure panels to complete the construction of the steel structure factory.

[0009] Preferably, the method of hoisting the grid onto the grid support in step 2 is specifically as follows:

[0010] The first step is to assemble the ground grid. Before assembly, the wires must be laid out to ensure that the four steel column supports corresponding to the grid support can pass through the grid.

[0011] The second step is to hoist the grid. Four truck cranes are used for hoisting, and the hoisting points are selected at the four steel columns corresponding to the grid supports.

[0012] The third step is to carry out high-altitude bulk installation. During installation, the installed grid frame must be temporarily supported by temporary support columns until the grid frame is installed to the next support and can only be removed;

[0013] Step 4: Continue to repeat step 3 until the entire grid is installed and fixed.

[0014] Preferably, the specific method for assembling and installing the wall steel structure panel is as follows: first, multiple horizontal supports are installed vertically correspondingly on the steel columns; then, the steel structure panels are welded on the horizontal supports; finally, the wall steel structure panels on multiple sides are assembled; a pair of symmetrical limit blocks are provided on opposite sides of the steel column, and multiple pairs are provided along the vertical intervals of the steel column, and multiple pairs of limit blocks of multiple steel columns on the same side are arranged one-to-one in the same horizontal plane, and multiple pairs of connecting blocks corresponding to each steel column are provided toward the steel column side of the horizontal support, which are respectively placed one-to-one on the multiple pairs of limit blocks, and the limit blocks are welded to the connecting blocks placed thereon, and the connecting blocks are also welded to the corresponding steel columns to realize the connection between the horizontal supports and the steel columns, and the limit blocks and the connecting blocks are equal in size and the projection diagrams completely overlap.

[0015] Preferably, the truss support comprises: a support body, which is fixed on the steel column and coincides with the central axis of the steel column; a matching seat, the top of which has a downwardly concave arc groove, the lower and middle parts of the lower chord ball of the truss just fit into the arc groove, the center of the matching seat has a downwardly concave connecting groove, which is a conical structure with a cylindrical structure on the upper part and a truncated cone structure on the lower part, the bolt hole in the lower chord ball is matched with a screw, the outer end of the screw protruding from the lower chord ball is connected to a matching block, which is also a conical structure with a cylindrical structure on the upper part and a truncated cone structure on the lower part, the upper part of the matching block and the upper part of the connecting groove The diameters are the same, and the inclination angle of the lower part of the matching block is slightly larger than the inclination angle of the lower part of the connecting groove; the limiting body includes a limiting frame and a pair of channel blocks, the limiting frame is a U-shaped structure, and the channel block has a through hole through which a pair of side rods of the limiting frame just pass, and the two opposite sides of the matching seat are symmetrically recessed inward to form a pair of channels that pass through the connecting groove, a pair of channel blocks are fixed on the outer side wall of the matching seat and correspond to the pair of channels, a pair of side rods of the limiting frame successively pass through the through holes of a pair of channel blocks and the channels in the matching seat, and then are tightly pressed against the top of the matching block, and the side rods are inclined toward the bottom of the matching block.

[0016] Preferably, a plurality of basic pads are detachably provided at the bottom of the support body of the grid support.

[0017] Preferably, the truss support also includes: a pair of clamps, which are respectively clamped on the upper and lower parts of the matching seat, the pair of clamps are connected as a whole through a connecting strip, the connecting strip is an arc-shaped structure that is close to the outer wall of the matching seat, and the pair of clamps and the connecting strip do not interfere with the limiting body; a pair of fixed supports, which are symmetrically arranged and do not interfere with the limiting body, the upper ends of the fixed supports are hinged to the outer sides of the upper clamps, and the lower ends are welded to the outer sides of the tops of the matching seats.

[0018] Preferably, before installing the roof panel layer, a purlin support plate is first welded on the support, which is L-shaped, and a main purlin support with a C-shaped cross-section is fixedly installed on the purlin support plate by bolts, and then a secondary purlin with a Z-shaped cross-section is vertically installed on the main purlin support, and then the roof panel layer is installed on the secondary purlin support, and the support is a sleeve type with an internal thread, and the upper chord ball of the grid is connected to the support by bolts.

[0019] The present invention has at least the following beneficial effects:

[0020] 1. This application adopts the structural form of square pyramid bolt ball flat grid, combined with steel column structure support, with high structural strength, strong bearing capacity and good seismic performance, so that the quality of the completed steel structure factory is guaranteed.

[0021] 2. The supporting steel column structure, grid, roof panel layer and the connections between them of this application can be prefabricated in advance or simply assembled on site to complete the construction, which greatly improves the construction efficiency, shortens the construction period, reduces labor costs, thereby reducing the construction budget and saving costs.

[0022] 3. The construction of this application is basically completed by simple on-site assembly or by a small car crane or a simple construction platform. No large-scale construction equipment is required, and the construction safety is high.

[0023] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the structure of the ground assembly of the grid of the present invention;

[0025] Figure 2 It is a structural schematic diagram of the hoisting of the grid frame of the present invention;

[0026] Figure 3 This is a schematic diagram of the structure of the high-altitude bulk grid of the present invention;

[0027] Figure 4 It is a structural schematic diagram of the grid structure unit of the present invention;

[0028] Figure 5It is a top view of the connection between the transverse support and the steel column of the present invention;

[0029] Figure 6 It is a schematic diagram of the structure of the mesh frame support and the lower chord ball of the mesh frame of the present invention;

[0030] Figure 7 It is an enlarged view of the installation structure below the roof panel layer of the present invention.

[0031] Description of reference numerals:

[0032] 1. Steel column, 2. Grid, 3. Truck crane, 4. Temporary support column, 5. Lower chord ball, 6. Upper chord ball, 7. Horizontal support, 8. Connecting block, 9. Support body, 10. Matching seat, 11. Screw, 12. Matching block, 13. Limit frame, 14. Channel block, 15. Side rod, 16. Clamp, 17. Fixed support, 18. Foundation pad, 19. Purlin support plate, 20. Support, 21. Main purlin support, 22. Secondary purlin support, 23. Roof panel layer. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0034] It should be noted that the experimental methods described in the following embodiments are conventional methods unless otherwise specified, and the reagents and materials are commercially available unless otherwise specified; in the description of the present invention, the terms "lateral", "longitudinal", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0035] The present invention provides a large-scale steel structure factory building construction process, comprising the following steps:

[0036] Step 1: Assemble the wall steel structure panels according to the relevant design requirements, and then install the steel column 1 as the column point support structure of the grid 2 and the support structure of the entire steel structure workshop according to the designed position, and set the grid support on the top of the steel column 1;

[0037] Step 2: Assemble the grid structure units and hoist them onto the grid support for installation. Grid 2 is a square pyramid bolt ball flat grid;

[0038] Step 3: Build the roof panel layer 23 on the assembled grid 2, and install the wall steel structure panels to complete the construction of the steel structure factory.

[0039] In the above technical solution, the wall steel structure panels are assembled in advance and installed directly in one step. The steel column 1 is directly supported according to the design position requirements. The grid 2 is also assembled in advance to form a grid structure unit and then hoisted and installed, thereby ensuring the construction quality while improving the construction efficiency and ensuring the construction safety. Before installing the grid 2, the grid support axis and elevation must be checked. The axis and elevation position of the grid 2 must meet the design requirements and relevant standards. After the roof panel layer 23 is built, the key parts must be tested for water leakage resistance. Before the installation of the grid 2, it is also necessary to re-measure the support points of the grid 2. This application is a column point support structure. The axis of the support points of each support of the grid 2 is corrected with a theodolite to ensure correctness. At the same time, the position of each steel column 1 support point is measured to ensure that it meets the requirements of the drawings. In addition, the embedded parts must be carefully inspected and accepted before the installation of the grid 2. The vertical and horizontal axes are popped up on the foundation, the foundation surface elevation is checked, and the center line is popped up on the four sides of the column. The height difference between adjacent support surfaces does not exceed 5mm, the axis offset of the support surface is not greater than 15mm, and the height difference between the highest and lowest support surfaces is not greater than 15mm. The reasonable setting of the grid structure unit makes the division of each unit block reasonable, greatly avoids plastic deformation during the hoisting process, and improves the installation quality. The installation of steel column 1 constitutes the support structure of the steel structure factory building, and then the wall steel structure panel is installed on the outside of the steel column 1 to form the outer wall of the steel structure factory building. The grid support is set on the top of the steel column 1 and the grid 2 is installed. Then the roof panel layer 23 is built to form the top shielding support structure of the steel structure factory building. At this point, the overall structural construction of the steel structure factory building is completed.

[0040] In another technical solution, Figures 1 to 4 As shown, the method of hoisting the grid 2 onto the grid support in step 2 is specifically as follows:

[0041] The first step is to assemble the ground grid 2. Before assembling, the wires must be laid out to ensure that the four steel columns 1 corresponding to the grid support can pass through the grid 2.

[0042] The second step is to hoist the grid 2, using four truck cranes 3 for hoisting, with the hoisting points being located at four steel columns 1 corresponding to the grid supports;

[0043] The third step is to carry out high-altitude bulk installation. During installation, the installed grid 2 must be temporarily supported by temporary support columns 4 until the grid 2 is installed to the next support and can be removed; the structural rods of the hoisted grid structure unit are supplemented, which is called bulk installation, so that the grid 2 structure meets the design size of the steel structure factory building;

[0044] Step 4: Continue to repeat step 3 until the entire grid frame 2 is installed and fixed.

[0045] In another technical solution, Figure 5As shown, the specific method of assembling and installing the wall steel structure panel is as follows: first, a plurality of transverse supports 7 are installed vertically correspondingly on the steel column 1; then, the steel structure panels are welded on the transverse supports 7; finally, the wall steel structure panels on multiple sides are assembled; a pair of symmetrical limit blocks are arranged on the opposite sides of the steel column 1, and multiple pairs are arranged along the vertical intervals of the steel column 1, and the multiple pairs of limit blocks of the multiple steel columns 1 on the same side are arranged one-to-one in the same horizontal plane, and the transverse supports 7 are arranged toward the steel column 1 side, and multiple pairs of connecting blocks 8 corresponding to each steel column 1 are placed one-to-one on the multiple pairs of limit blocks, respectively, and the limit blocks are welded to the connecting blocks 8 placed thereon, and the connecting blocks 8 are also welded to the corresponding steel columns 1, so as to realize the connection between the transverse supports 7 and the steel columns 1, and the limit blocks and the connecting blocks 8 are equal in size and the projection diagrams completely overlap.

[0046] In the above technical solution, if the transverse support 7 is installed by welding in the traditional way or connected to the steel column 1 by bolts, it is necessary to use supporting equipment such as position calibration, which is cumbersome to construct, and the horizontal position of the transverse support 7 also needs to be adjusted continuously until it meets the actual requirements. In the technical solution of the present application, a limit block is correspondingly set on the steel column 1. The position and elevation of the steel column 1 have been adjusted to meet the design requirements in the above steps. The corresponding limit blocks have reached the design requirements in both vertical and horizontal elevations. Therefore, multiple pairs of connecting blocks 8 on the transverse support 7 are placed on the limit blocks one by one, and then welded to achieve temporary placement and welding. Not only does it not need to adjust the elevation of the transverse support 7, but it also does not need a temporary fixing bracket when welding the transverse support 7. A pair of connecting blocks 8 and the transverse support 7 just form a U-shaped structure to wrap the steel column 1, achieving multi-directional welding fixation, and the fixing firmness is also strong.

[0047] In another technical solution, Figure 6 As shown, the grid support comprises:

[0048] A support body 9, which is fixed on the steel column 1 and coincides with the central axis of the steel column 1;

[0049] The matching seat 10 has a downwardly concave arc groove on its top, and the middle and lower part of the lower chord ball 5 of the grid 2 just fits in the arc groove. The matching seat 10 has a downwardly concave connecting groove in the center, which is a conical structure with a cylindrical structure on the upper part and a truncated cone structure on the lower part. The bolt hole in the lower chord ball 5 is matched with a screw rod 11, and the outer end of the screw rod 11 protruding from the lower chord ball 5 is connected to a matching block 12, which is also a conical structure with a cylindrical structure on the upper part and a truncated cone structure on the lower part. The upper part of the matching block 12 has the same diameter as the upper part of the connecting groove, and the inclination angle of the lower part of the matching block 12 is slightly larger than the inclination angle of the lower part of the connecting groove.

[0050] The limiting body includes a limiting frame 13 and a pair of channel blocks 14. The limiting frame 13 is a U-shaped structure. The channel block 14 has through holes through which a pair of side rods 15 of the limiting frame 13 just pass. The two opposite sides of the matching seat 10 are symmetrically recessed inward to form a pair of channels that pass through the connecting groove. A pair of channel blocks 14 are fixed on the outer side walls of the matching seat 10 and correspond to the pair of channels. The pair of side rods 15 of the limiting frame 13 sequentially pass through the through holes of a pair of channel blocks 14 and the channels in the matching seat 10, and then tightly abut against the top of the matching block 12. The side rods 15 are inclined toward the bottom of the matching block 12.

[0051] In the above technical solution, the grid support is connected to the steel column 1 through the support body 9, and the cross-section of the grid support is larger than the cross-section of the steel column 1, so that the support area of ​​the grid support is large and the support strength is high. The grid support cooperates with the lower chord ball 5 through the matching seat 10, so that the grid support and the lower chord ball 5 are convenient to install and disassemble. First, the screw 11 is connected to the bolt hole of the lower chord ball 5, and then the screw 11 is connected to the matching block 12. The central axis is kept coincident during the connection, and the connected structure is inserted downward into the connection groove of the matching seat 10. The arc surface of the lower chord ball 5 is tightly matched with the arc groove of the matching seat 10, and then pressed downward so that the lower inclined surface of the matching block 12 is tightly against the lower inclined surface of the bite connection groove. In order to further ensure the connection firmness and connection strength between the lower chord ball 5 and the matching seat 10, the matching block 12 is limited by inserting the limiting frame 13, which is also to further limit the lower chord ball 5. The inclined surface of the side rod 15 of the limiting frame 13 facilitates it to smoothly enter the top surface of the matching block 12 and press down against the matching block 12. The bottom rod of the limiting frame 13 is used as a fulcrum during installation and disassembly.

[0052] In another technical solution, a plurality of foundation blocks 18 are detachably provided at the bottom of the support body 9 of the grid support. The elevation of the support point of the steel column 1 is measured with a level, and the elevation error of each adjacent support point is within 5 mm. If it exceeds the range, the foundation blocks 18 are welded at the bottom of the support body 9 for leveling. The number and thickness of the foundation blocks 18 are set according to the actual elevation measurement error.

[0053] In another technical solution, Figure 6 As shown, the grid support also includes: a pair of clamps 16, which are respectively clamped on the upper and lower parts of the matching seat 10, and the pair of clamps 16 are connected as a whole through a connecting strip, and the connecting strip is an arc-shaped structure that is close to the outer wall of the matching seat 10, and the pair of clamps 16 and the connecting strip do not interfere with the limiting body; a pair of fixed supports 17, which are symmetrically arranged and do not interfere with the limiting body, and the upper ends of the fixed supports 17 are hinged to the outer side of the upper clamps 16, and the lower ends are welded to the outer side of the top of the matching seat 10.

[0054] In the above technical solution, the lower part of the grid support 2 fulcrum of the grid support should be properly reinforced to avoid excessive stress on the grid support 2 and sinking of the grid 2. Therefore, the grid support is further supported and strengthened by setting a clamp 16 and a fixed support 17. The clamp 16 is an existing clamp 16 structure, which is set according to the size of the limit seat and clamped on the limit seat. A pair of clamps 16 are connected as a whole by a connecting strip, which is convenient for storage and installation positioning. A pair of fixed supports 17 are used for side reinforcement. According to the welding position, the lower end is welded to the support body 9 to achieve side reinforcement.

[0055] In another technical solution, Figure 7 As shown, before the installation of the roof panel layer 23, the purlin support plate 19 is first welded on the support 20, which is L-shaped, and the main purlin support 21 is bolted on the purlin support plate 19, and its cross-section is C-shaped. Then, the secondary purlin is vertically installed on the main purlin support 21, which is Z-shaped, and then the roof panel layer 23 is installed on the secondary purlin support 22. The support 20 is a sleeve type with an internal thread, and the upper chord ball 6 of the grid 2 is connected to the support 20 by bolts.

[0056] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. The construction process of large steel structure workshop is characterized by: The steps include: Step 1: Assemble the wall steel structure panels according to the relevant design requirements, and then install the steel columns as the column point support structure of the grid and the support structure of the entire steel structure workshop according to the designed position, and set the grid support on the top of the steel column; Step 2: Assemble the grid structure unit and hoist it onto the grid support for installation. The grid is a square pyramid bolt ball flat grid; The grid support comprises: A support body, which is fixed on the steel column and coincides with the central axis of the steel column; A matching seat, the top of which has an arc groove that is sunken downwards, the middle and lower part of the lower chord ball of the grid frame just fits into the arc groove, the center of the matching seat has a connection groove that is sunken downwards, which is a conical structure with a cylindrical structure at the top and a truncated cone structure at the bottom, the bolt hole in the lower chord ball is matched and connected with a screw rod, the outer end of the screw rod protruding from the lower chord ball is connected with a matching block, which is also a conical structure with a cylindrical structure at the top and a truncated cone structure at the bottom, the upper part of the matching block has the same diameter as the upper part of the connection groove, and the inclination angle of the lower part of the matching block is slightly larger than the inclination angle of the lower part of the connection groove; The limiting body comprises a limiting frame and a pair of channel blocks, wherein the limiting frame is a U-shaped structure, the channel block has through holes through which a pair of side rods of the limiting frame just pass, the two opposite sides of the matching seat are symmetrically recessed inward to form a pair of channels that pass through to the connecting groove, a pair of channel blocks are fixed on the outer side wall of the matching seat and correspond to the pair of channels, a pair of side rods of the limiting frame sequentially pass through the through holes of a pair of channel blocks and the channels in the matching seat, and then are tightly pressed against the top of the matching block, and the side rods are inclined toward the bottom of the matching block; First, connect the screw rod to the bolt hole of the lower chord ball, and then connect the screw rod to the matching block. When connecting, keep the central axis coincident, insert the connected structure downward into the connecting groove of the matching seat, and make the arc surface of the lower chord ball fit tightly with the arc groove of the matching seat, and then press downward so that the lower inclined surface of the matching block is tightly against the lower inclined surface of the bite connection groove; in order to further ensure the connection firmness and connection strength between the lower chord ball and the matching seat, limit the matching block by inserting the limit frame, which is also to further limit the lower chord ball. The side rod inclined surface of the limit frame is set to facilitate it to smoothly enter the top surface of the matching block and press downward against the matching block; Step 3: Build the roof panel layer on the assembled grid, and install the wall steel structure panels to complete the construction of the steel structure factory.

2. The large-scale steel structure factory building construction process as claimed in claim 1 is characterized in that: The method of hoisting the grid onto the grid support in step 2 is specifically as follows: The first step is to assemble the ground grid. Before assembly, the wires must be laid out to ensure that the four steel column supports corresponding to the grid support can pass through the grid. The second step is to hoist the grid. Four truck cranes are used for hoisting, and the hoisting points are selected at the four steel columns corresponding to the grid supports. The third step is to carry out high-altitude bulk installation. During installation, the installed grid frame must be temporarily supported by temporary support columns until the grid frame is installed to the next support and can only be removed; Step 4: Continue to repeat step 3 until the entire grid is installed and fixed.

3. The large-scale steel structure factory building construction process as claimed in claim 1 is characterized in that: The specific method for assembling and installing the wall steel structure panel is as follows: first, multiple horizontal supports are installed vertically correspondingly on the steel column; then, the steel structure panels are welded on the horizontal supports; finally, the wall steel structure panels on multiple sides are assembled; a pair of symmetrical limit blocks are arranged on the opposite sides of the steel column, and multiple pairs are arranged along the vertical intervals of the steel column, and multiple pairs of limit blocks of multiple steel columns on the same side are arranged one-to-one in the same horizontal plane, and multiple pairs of connecting blocks corresponding to each steel column are arranged toward the steel column side of the horizontal support, which are placed one-to-one on the multiple pairs of limit blocks, respectively, and the limit blocks are welded to the connecting blocks placed thereon, and the connecting blocks are also welded to the corresponding steel columns to realize the connection between the horizontal supports and the steel columns, and the limit blocks and the connecting blocks are equal in size and the projection diagrams completely overlap.

4. The large-scale steel structure factory building construction process as claimed in claim 1 is characterized in that: The bottom of the support body of the grid support is detachably provided with a plurality of basic pads.

5. The large-scale steel structure factory building construction process as claimed in claim 1 is characterized in that: The grid support also includes: A pair of clamps, which are respectively clamped with the upper part and the lower part of the matching seat, and the pair of clamps are connected as a whole by a connecting strip, and the connecting strip is an arc-shaped structure that is close to the outer side wall of the matching seat, and the pair of clamps and the connecting strip do not interfere with the limiting body; A pair of fixing supports are symmetrically arranged and do not interfere with the limiting body. The upper ends of the fixing supports are hinged to the outer side of the upper clamp, and the lower ends are welded to the outer side of the top of the matching seat.

6. The large-scale steel structure factory building construction process as claimed in claim 1, characterized in that: Before installing the roof panel layer, firstly weld the purlin support plate on the support, which is L-shaped, and bolt the main purlin support on the purlin support plate, whose cross section is C-shaped, and then vertically install the secondary purlin on the main purlin support, which is Z-shaped, and then install the roof panel layer on the secondary purlin support. The support is a sleeve type with an internal thread, and the upper chord ball of the grid is connected to the support by bolts.

Images