A construction technology of super-large span fish belly roof truss

Abstract

The invention discloses a construction process of a super-large span fish-belly roof truss, which includes assembling a frame; checking the appearance dimensions of the parts in each component before welding, and correcting the appearance dimensions that are out of tolerance; closing the straight web and the diagonal web themselves; making and closing the lower chord and the upper chord; making and closing the support nodes; finally, assembling and welding the lower chord, the support nodes, the upper chord, the straight web and the diagonal web; and welding the stiffening plate and the connecting plate. The invention divides each component into parts, and all part plates are CNC typesetting and cutting, preferably CNC plasma cutting to reduce the deformation caused by cutting. The support nodes are assembled by the positive manufacturing integral assembly method to ensure that the manufacturing accuracy requirements of the single component meet the requirements of on-site assembly and design. The connection and welding between the various components adopt different welding and groove methods according to their structural characteristics and the needs of later installation and bearing, thereby optimizing the construction process.

Description

Technical Field

[0001] The invention belongs to the technical field of steel structure buildings, and particularly relates to a construction process for a super-large span fish-belly type roof truss. Background Art

[0002] The construction site of the National Convention Center Phase II project is located north of Datun Road, adjacent to Tianchen East Road in the east and Tianchen West Road in the west. Datun North Road passes under the main building and connects to the Ao Sen Park Station of Metro Line 15. The building functions as a convention and exhibition center, mainly used for holding state affairs, government affairs and high-end international exchanges. The total construction area of ​​the project is about 409,000 square meters, mainly divided into three floors above ground and two floors underground (partially with mezzanines). The underground building has a floor plan size of 456 meters × 180 meters, with a total construction area of ​​about 153,000 square meters, and its main functions are convention and exhibition, garage, and machine room; the floor plan size of the above-ground building is 456 meters × 144 meters, with a total construction area of ​​about 256,000 square meters, and its main functions are convention and exhibition center, supporting office logistics, etc. The overall building height is 45 meters (the roof height is 52 meters).

[0003] The roof of the National Convention Center project adopts a large-span plane arc truss and cylindrical space lattice shell structure system. Because of its large span, the existing structure cannot meet its construction requirements. Even if there is a large-span truss structure in the existing steel structure, its unreasonable structural design will affect its safety and stability in use. In addition, due to its large span, the high precision requirements for its production and installation during the construction process are the difficulties and key points of the processing of the super-large span fish belly roof truss. Summary of the invention

[0004] Purpose of the invention: In order to overcome the above shortcomings, the purpose of the present invention is to provide a construction process for a super-large span fish-belly roof truss. The construction process of the super-large span fish-belly roof truss described in the present invention divides the upper chord, lower chord, straight web, diagonal web, corbel, support node, stiffening plate, etc. into parts, and all part plates are CNC typesetting and cutting, preferably CNC plasma cutting to reduce the deformation caused by cutting. According to the structural characteristics of the support node itself, it is planned to adopt the positive overall assembly method for assembly to ensure that the manufacturing accuracy requirements of the single component meet the requirements of on-site assembly and design; the connection and welding between the various components adopt different welding and beveling methods according to their structural characteristics and the needs of later installation and load-bearing, thereby optimizing the construction process and further improving the welding and construction quality.

[0005] Technical solution: In order to achieve the above purpose, the present invention provides a construction process of a super-large span fish belly roof truss, and the specific construction process is as follows:

[0006] 1): Tire frame assembly. The tire frame needs to maintain its strong rigidity and the gap needs to be controlled during assembly. The tire frame template must be assembled using a special machined and planed template;

[0007] 2): Check the appearance dimensions of each component before welding, and make corrections if the appearance dimensions are out of tolerance;

[0008] 3): The straight and diagonal webs close together;

[0009] 4): Make the lower and upper strings and close them;

[0010] 5): Make and close the support nodes;

[0011] 6): Finally, assemble and weld the lower chord, support node, upper chord, straight web and diagonal web, that is, first hoist the lower chord on the pre-assembled assembly frame for precision control; hoist the upper chord on the pre-assembled assembly frame for precision control; secondly, hoist the truss diagonal web on the pre-assembled assembly frame for precision control; finally, hoist the truss straight web on the pre-assembled assembly frame for precision control;

[0012] 7): Install and weld stiffening plates and connecting plates, and use T-shaped welds to weld each component to the member. The connecting groove form adopts the double-sided welding form of T-shaped welds. When the operating space is less than 80mm, the single-sided groove form of T-shaped welds is adopted, and the withdrawal method is adopted. The construction process of a super-large span fish belly roof truss described in the present invention divides the upper chord, lower chord, straight web, diagonal web, corbel, support node, stiffening plate, etc. into parts. All part plates are CNC typesetting and cutting, and CNC plasma cutting is preferred to reduce the deformation caused by cutting. According to the structural characteristics of the support node itself, it is planned to adopt the positive overall assembly method for assembly to ensure that the manufacturing accuracy requirements of the single component meet the requirements of on-site assembly and design. At the same time, the connection and welding between the various components adopt different welding and groove methods according to their structural characteristics and the needs of later installation and load-bearing, which optimizes the construction process and further improves its welding and construction quality.

[0013] In the construction process of the super-large span fish-belly roof truss described in the present invention, in the step 3), the straight web members and the diagonal web members are both made of hot-rolled H-shaped steel during the manufacturing process, and their lengths are ensured during the processing, and the web member tolerance is required to be -2mm~3mm. At the same time, the bolt hole spacing accuracy of the two-port web plate needs to be controlled within -1mm~+1mm.

[0014] The construction process of the super-large span fish belly roof truss described in the present invention, the specific manufacturing method of the lower chord and the upper chord in step 4) is as follows: 1): first use CP welding to weld the lower chord and the upper chord, and use full penetration welding in the node area and 600mm on the left and right, and the length tolerance of the upper chord (3) is required to be -4mm~6mm;

[0015] 2): The bracket structure, vertical bracket and side bracket are welded by partial penetration welds, and the groove at the connection is welded on both sides by T-type welds;

[0016] 3): The corner joint or butt joint between the transfer node and the H-chord flange plate in the upper chord and the frame is welded with full penetration welding, and the groove at the connection between the structures is welded with root cleaning. When there is an angle in the structure, the groove is oriented in the obtuse angle direction.

[0017] The construction process of the super-large span fish-belly roof truss described in the present invention is characterized in that the support nodes in the step 5) are assembled by the positive integral assembly method, and the specific production method is as follows: 1): firstly, the support nodes are self-assembled, that is, the H-type support is self-closed and welded by full penetration welding, and the connection grooves of each component are root-clearing welded;

[0018] 2): Assemble and weld the support base plate and the H-type support, that is, use full penetration welding to weld the support base plate and the H-type support, and use root cleaning welding groove at the connection;

[0019] 3): Install and weld the vertical stiffener. The corner joint between the vertical stiffener and the support bottom plate is fixed by full penetration welding. The connecting groove adopts the root cleaning welding groove form. The vertical stiffener and the web of the H-type support are welded and fixed by T-type welds, and the connecting groove adopts the T-type weld double-sided welding form;

[0020] 4): Install and weld the horizontal stiffener. Full penetration welding is used between the horizontal stiffener and the flange plate and vertical stiffener of the H-type support. The groove at the connection is welded with a pad. The horizontal stiffener and the web of the H-type support are welded and fixed with a T-weld. The connected groove adopts a T-weld single-sided groove.

[0021] 5): The fillet joint between the upper chord plate in the upper chord and the outer plate in the H-type support adopts full penetration welding, and the groove form of the connection adopts the root cleaning welding groove. It is welded and fixed with the web plate in the H-type support by T-type weld, and the groove form adopts the double-sided groove form of T-type weld. The fillet weld between the inner plate in the H-type support adopts full penetration welding, and the groove form adopts the pad welding form;

[0022] 6): The fillet weld between the upper chord web and the H-shaped support is fixed by T-shaped weld, and the groove form of the connection is T-shaped weld double-sided welding;

[0023] 7): Install and weld the full-length horizontal stiffener plate. The full-length horizontal stiffener plate and the vertical stiffener plate are welded by full penetration welding. The connecting groove adopts the root-clearing welding groove form. The full-length horizontal stiffener plate and the inner and outer plates of the H-type support are welded by full penetration welding. The groove form adopts the pad welding groove form. The full-length horizontal stiffener plate and the web of the H-type support will be welded by T-type welds. The groove form is a T-type weld single-sided groove form, and the grooves are all opened toward the lower side;

[0024] 8): A plate is used to seal the triangular space formed between the full-length horizontal stiffener, the H-shaped support and the upper chord plate.

[0025] The construction process of a super-large span fish-belly roof truss described in the present invention comprises: a super-large span fish-belly roof truss, wherein the super-large span fish-belly roof truss comprises a lower chord, a group of support nodes, an upper chord, a group of straight web members and a group of diagonal web members, the support nodes are arranged at both ends of the lower chord, the upper chord is arranged above the lower chord, and both ends thereof are connected to the support nodes, the straight web member is vertically arranged between the lower chord and the upper chord, and the diagonal web member is arranged between the lower chord and the upper chord, and is arranged between the two straight web members.

[0026] The construction process of the super-large span fish-belly roof truss described in the present invention is as follows: the upper chord includes an upper chord truss and a group of transition nodes, the transition node is arranged below the upper chord truss, and the upper parts of the straight web members and the diagonal web members are connected to the transition node; the upper chord truss adopts an H-type truss, which includes an upper chord plate, a lower chord plate and an upper chord web plate, the upper chord plate and the lower chord plate are arranged opposite to each other, the upper chord web plate is arranged between the upper chord plate and the lower chord plate, and reinforcement components are provided on both sides of the upper chord web plate between the upper chord plate and the lower chord plate; the transition node is V-shaped, which includes a group of corbel structures, the corbel structures are symmetrically arranged, and the corbel structures all include a first side plate, a second side plate and a group of web plates, the first side plate and the second side plate are arranged opposite to each other, the web plate is arranged between the first side plate and the second side plate, and the side of the web plate away from the first side plate is connected to the second side plate by an arc guard plate.

[0027] The construction process of the super-large span fish belly roof truss described in the present invention, the support node includes a support bottom plate, an H-shaped support, a vertical stiffening plate, and a horizontal stiffening plate, the H-shaped support is arranged above the support bottom plate, the vertical stiffening plate is arranged on one side of the web of the H-shaped support, and the horizontal stiffening plate is arranged on both sides of the vertical stiffening plate and connected to the H-shaped support;

[0028] The support node also includes a full-length horizontal stiffener plate, which is arranged on the top of the vertical stiffener plate and is connected to the H-shaped support;

[0029] The upper part of the H-shaped support is arranged in an inclined shape, the lower chord is arranged on one side of the H-shaped support, the end of the upper chord plate in the upper chord extends to the H-shaped support, and the two cooperate with each other, and a triangular space is formed between the full-length horizontal stiffening plate, the H-shaped support and the upper chord plate.

[0030] The super-large spanning fish belly roof truss described in the present invention, the lower chord includes a lower chord top plate, a lower chord bottom plate and a lower chord web plate, the lower chord top plate and the lower chord bottom plate are arranged opposite to each other, and the lower chord web plate is vertically arranged between the lower chord top plate and the lower chord bottom plate.

[0031] The super-large span fish belly type roof truss described in the present invention further comprises a lower chord stiffening plate in the lower chord, and the lower chord stiffening plate is arranged between the lower chord top plate and the lower chord bottom plate and on both sides of the lower chord web plate.

[0032] The super-large span fish-belly roof truss described in the present invention is characterized in that a group of vertical corbels and side corbels are provided on the lower chord, and the lower parts of the straight web members and the diagonal web members are respectively connected to the corresponding vertical corbels and side corbels.

[0033] It can be seen from the above technical solution that the present invention has the following beneficial effects:

[0034] 1. The construction process of the super-large span fish-belly roof truss described in the present invention divides the upper chord, lower chord, straight web, diagonal web, corbel, support node, stiffening plate, etc. into parts. All part plates are CNC typesetting and cutting, preferably CNC plasma cutting to reduce the deformation caused by cutting. According to the structural characteristics of the support node itself, it is planned to adopt the positive overall assembly method for assembly to ensure that the manufacturing accuracy requirements of the single component meet the requirements of on-site assembly and design. At the same time, the connection and welding between the various components adopt different welding and groove methods according to their structural characteristics and the needs of later installation and load-bearing, thereby optimizing the construction process and further improving the welding and construction quality.

[0035] 2. The present invention adopts a very strong rigid frame for the frame assembly, which can effectively ensure the positioning of the support and truss and keep it from settling during the manufacturing process. At the same time, the machined and planed special template is erected and assembled, which can effectively improve the assembly accuracy of the roof truss.

[0036] 3. The super-large span fish-belly roof truss described in the present invention has a simple structure and a reasonable design. The upper chord and the lower chord are connected by support nodes to form a fish-belly structure, thereby increasing the span of the roof truss. A straight web and an oblique web are provided between the upper chord and the lower chord, thereby greatly improving the stability of the connection between the upper chord and the lower chord, and improving the firmness of the entire roof truss structure, thereby effectively improving the safety and stability of its use.

[0037] 4. The upper chord described in the present invention includes an upper chord truss and a group of transfer nodes. The transfer nodes are V-shaped and adopt a unique structural design. While ensuring its structural stability, it can also be connected with straight web members and diagonal web members at the same time, thereby optimizing the structure of the entire roof truss and allowing it to better meet construction needs.

[0038] 5. The arrangement of vertical stiffeners, horizontal stiffeners and full-length horizontal stiffeners in the support nodes of the present invention greatly improves the firmness and stability of the structure.

[0039] 6. The upper part of the H-shaped support described in the present invention is arranged in an inclined shape, so that it can better cooperate with the upper chord and improve the stability of the connection between the two. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a structural schematic diagram of the super-large span fish belly type roof truss of the present invention;

[0041] Figure 2 It is a partial installation diagram of the lower chord in the present invention;

[0042] Figure 3 It is a partial installation diagram of the lower chord, support node and upper chord in the present invention;

[0043] Figure 4 It is a schematic diagram of the installation of the transfer node in the present invention;

[0044] Figure 5 It is a schematic diagram of the installation of the vertical corbel and the side corbel in the present invention. DETAILED DESCRIPTION

[0045] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0046] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "clockwise", "counterclockwise" 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, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0047] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more, unless otherwise clearly specified.

[0048] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0050] Example 1

[0051] The construction process of a super-large span fish belly type roof truss described in this embodiment is as follows:

[0052] 1): Tire frame assembly. The tire frame needs to maintain its strong rigidity and the gap needs to be controlled during assembly. The tire frame template must be assembled using a special machined and planed template;

[0053] 2): Check the appearance dimensions of each component before welding, and make corrections if the appearance dimensions are out of tolerance;

[0054] 3): The straight web member 4 and the diagonal web member 5 close together;

[0055] 4): Make the lower string 1 and the upper string 3 and close them;

[0056] 5): Make and close the support node 2;

[0057] 6): Finally, assemble and weld the lower chord 1, support node 2, upper chord 3, straight web member 4 and diagonal web member 5, that is, first hoist the lower chord 1 on the pre-assembled assembly frame for precision control; hoist the upper chord 3 on the pre-assembled assembly frame for precision control; secondly, hoist the truss diagonal web member 5 on the pre-assembled assembly frame for precision control; finally, hoist the truss straight web member 4 on the pre-assembled assembly frame for precision control;

[0058] 7): When welding stiffeners and connecting plates, all components and members will be welded using T-shaped welds. The connecting grooves are double-sided T-shaped welds. When the operating space is less than 80mm, single-sided T-shaped welds are used, and the withdrawal method is used.

[0059] In the construction process of a super-large span fish-belly roof truss described in this embodiment, in the step 3, the straight web members 4 and the diagonal web members 5 are both made of hot-rolled H-shaped steel during the manufacturing process, and their lengths are ensured during the processing, and the web member tolerance is required to be -2mm~3mm. At the same time, the bolt hole spacing accuracy of the two-port web plate needs to be controlled within -1mm~+1mm.

[0060] In the construction process of a super-large span fish belly roof truss described in this embodiment, the specific manufacturing method of the lower chord 1 and the upper chord 3 in step 4 is as follows: 1): first use CP welding to weld the lower chord 1 and the upper chord 3, and use full penetration welding in the node area and 600mm on the left and right, and the length tolerance of the upper chord (3) is required to be -4mm~6mm;

[0061] 2): The bracket structure, the vertical bracket 15 and the side bracket 16 are welded by partial penetration welds, and the grooves at the joints are welded on both sides by T-type welds;

[0062] 3): The corner joint or butt joint between the transfer node 32 and the H-type chord flange plate in the upper chord 3 and the frame adopts full penetration welding, and the groove at the connection between the structures adopts root cleaning welding. When there is an angle in the structure, the groove is oriented in the obtuse angle direction.

[0063] In the construction process of a super-large span fish-belly roof truss described in this embodiment, the support node 2 in step 5 is assembled by the positive integral assembly method, and the specific production method is as follows: 1): firstly, the support node 2 is self-assembled, that is, the H-shaped support 22 is self-closed and welded by full penetration welding, and the connection grooves of each component are welded by root cleaning;

[0064] 2): Assemble and weld the support base plate 21 and the H-shaped support 22, that is, use full penetration welding to weld the support base plate 21 and the H-shaped support 22, and use root cleaning welding groove at the connection;

[0065] 3): Install and weld the vertical stiffener 23. The corner joint between the vertical stiffener 23 and the support bottom plate 21 is fixed by full penetration welding. The connected groove adopts the root cleaning welding groove form. The vertical stiffener 23 and the web of the H-shaped support 22 are welded and fixed by T-shaped welds, and the connected groove adopts the T-shaped weld double-sided welding form;

[0066] 4): Install and weld the horizontal stiffener 24. Full penetration welding is adopted between the horizontal stiffener 24 and the flange plate and vertical stiffener 23 of the H-shaped support 22. The groove at the connection adopts the pad welding form. The horizontal stiffener 24 and the web of the H-shaped support 22 are welded and fixed by T-shaped welds, and the groove of the connection adopts the single-sided groove form of T-shaped welds;

[0067] 5): The fillet joint between the upper chord plate 311 in the upper chord 3 and the outer plate in the H-shaped support 22 adopts full penetration welding, and the groove form of the connection adopts the root cleaning welding groove. The web plate in the H-shaped support 22 is welded and fixed by T-weld method, and the groove form adopts the double-sided groove form of T-weld. The fillet weld between the inner plate in the H-shaped support 22 adopts full penetration welding, and the groove form adopts the pad welding form;

[0068] 6): The fillet weld between the upper chord web 313 and the H-shaped support 22 is fixed by T-shaped weld welding, and the groove form of the connection is a double-sided T-shaped weld;

[0069] 7): Install and weld the full-length horizontal stiffener 25. The full-length horizontal stiffener 25 and the vertical stiffener 23 are welded by full penetration welding. The connecting groove adopts the root-clearing welding groove form. The full-length horizontal stiffener 25 and the inner and outer plates of the H-shaped support 22 are welded by full penetration welding. The groove form adopts the pad welding groove form. The full-length horizontal stiffener 25 and the web of the H-shaped support 22 will be welded by T-shaped welds. The groove form is a T-shaped weld single-sided groove form, and the grooves are all opened toward the lower side;

[0070] 8): A plate is used to seal the triangular space formed between the full-length horizontal stiffener 25, the H-shaped support 22 and the upper chord plate 311.

[0071] Example 2

[0072] like Figures 1 to 5 An extra-large span fish-belly roof truss shown includes a lower chord 1, a group of support nodes 2, an upper chord 3, a group of straight web members 4 and a group of diagonal web members 5, wherein the support nodes 2 are arranged at both ends of the lower chord 1, the upper chord 3 is arranged above the lower chord 1, and both ends thereof are connected to the support nodes 2, the straight web members 4 are vertically arranged between the lower chord 1 and the upper chord 3, and the diagonal web members 5 are arranged between the lower chord 1 and the upper chord 3, and between the two straight web members 4.

[0073] In this embodiment, the upper chord 3 includes an upper chord truss 31 and a group of transfer nodes 32, wherein the transfer node 32 is arranged below the upper chord truss 31, and the upper parts of the straight web members 4 and the diagonal web members 5 are connected to the transfer node 32; the upper chord truss 31 adopts an H-shaped truss, which includes an upper chord plate 311, a lower chord plate 312 and an upper chord web plate 313, wherein the upper chord plate 311 and the lower chord plate 312 are arranged opposite to each other, and the upper chord web plate 313 is arranged between the upper chord plate 311 and the lower chord plate 312, and the upper chord plate 311 and the lower chord plate 312 are arranged opposite to each other, and the upper chord web plate 313 is arranged between the upper chord plate 311 and the lower chord plate 312. Reinforcement components 314 are provided on both sides of the upper chord web 313; the transition node 32 is V-shaped, and includes a group of corbel structures, which are symmetrically arranged, and each corbel structure includes a first side plate 321, a second side plate 322 and a group of webs 323, the first side plate 321 and the second side plate 322 are arranged opposite to each other, the web 323 is arranged between the first side plate 321 and the second side plate 322, and the side of the web 323 away from the first side plate 321 is connected to the second side plate 322 through an arc guard plate 324.

[0074] The support node 2 in this embodiment includes a support base plate 21, an H-shaped support 22, a vertical stiffening plate 23, and a horizontal stiffening plate 24. The H-shaped support 22 is arranged above the support base plate 21, the vertical stiffening plate 23 is arranged on one side of the web of the H-shaped support 22, and the horizontal stiffening plate 24 is arranged on both sides of the vertical stiffening plate 23 and connected to the H-shaped support 22.

[0075] The support node 2 further includes a full-length horizontal stiffener 25, which is disposed on the top of the vertical stiffener 23 and is connected to the H-shaped support 22;

[0076] The upper part of the H-shaped support 22 is arranged in an inclined shape, the lower chord 1 is arranged on one side of the H-shaped support 22, the end of the upper chord plate 311 in the upper chord 3 extends to the H-shaped support 22, and the two cooperate with each other, and a triangular space is formed between the full-length horizontal stiffening plate 25 and the H-shaped support 22 and the upper chord plate 311.

[0077] In this embodiment, the lower chord 1 comprises a lower chord top plate 11 , a lower chord bottom plate 12 and a lower chord web plate 13 . The lower chord top plate 11 and the lower chord bottom plate 12 are arranged opposite to each other, and the lower chord web plate 13 is vertically arranged between the lower chord top plate 11 and the lower chord bottom plate 12 .

[0078] The lower chord 1 in this embodiment further includes a lower chord stiffening plate 14 . The lower chord stiffening plate 14 is arranged between the lower chord top plate 11 and the lower chord bottom plate 12 , and is arranged on both sides of the lower chord web plate 13 .

[0079] In this embodiment, a group of vertical corbels 15 and lateral corbels 16 are provided on the lower chord 1, and the lower parts of the straight web members 4 and the diagonal web members 5 are respectively connected to the corresponding vertical corbels 15 and lateral corbels 16.

[0080] The above description is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements without departing from the principle of the present invention, and these improvements should also be regarded as within the protection scope of the present invention.

Claims

1. A construction process for a super-large span fish belly roof truss, characterized by: An extra-large span fish-belly roof truss, the extra-large span fish-belly roof truss comprising a lower chord (1), a group of support nodes (2), an upper chord (3), a group of straight web members (4) and a group of diagonal web members (5), the support nodes (2) being arranged at two ends of the lower chord (1), the upper chord (3) being arranged above the lower chord (1), and having two ends connected to the support nodes (2), the straight web member (4) being arranged vertically between the lower chord (1) and the upper chord (3), and the diagonal web member (5) being arranged between the lower chord (1) and the upper chord (3), and being arranged between the two straight web members (4); The upper chord (3) comprises an upper chord truss (31) and a group of transition nodes (32), wherein the transition node (32) is arranged below the upper chord truss (31), and the upper parts of the straight web members (4) and the diagonal web members (5) are connected to the transition node (32); the upper chord truss (31) adopts an H-shaped truss, which comprises an upper chord plate (311), a lower chord plate (312) and an upper chord web plate (313), wherein the upper chord plate (311) and the lower chord plate (312) are arranged opposite to each other, the upper chord web plate (313) is arranged between the upper chord plate (311) and the lower chord plate (312), and reinforcement components (314) are arranged between the upper chord plate (311) and the lower chord plate (312) on both sides of the upper chord web plate (313); the transition node (32) is V-shaped, and comprises a group of bracket structures, wherein the bracket structures are symmetrically arranged, and the bracket structures are The structure comprises a first side plate (321), a second side plate (322) and a group of web plates (323), wherein the first side plate (321) and the second side plate (322) are arranged opposite to each other, the web plate (323) is arranged between the first side plate (321) and the second side plate (322), and the side of the web plate (323) away from the first side plate (321) is connected to the second side plate (322) via an arc-shaped guard plate (324); the support node (2) comprises a support base plate (21), an H-shaped support (22), a vertical stiffening plate (23) and a horizontal stiffening plate (24), wherein the H-shaped support (22) is arranged above the support base plate (21), the vertical stiffening plate (23) is arranged on one side of the web plate of the H-shaped support (22), and the horizontal stiffening plate (24) is arranged on both sides of the vertical stiffening plate (23) and connected to the H-shaped support (22); The support node (2) further comprises a full-length horizontal stiffening plate (25), wherein the full-length horizontal stiffening plate (25) is arranged on the top of the vertical stiffening plate (23) and is connected to the H-shaped support (22); The upper part of the H-shaped support (22) is arranged in an inclined shape, the lower chord (1) is arranged on one side of the H-shaped support (22), the end of the upper chord plate (311) in the upper chord (3) extends to the H-shaped support (22), and the two cooperate with each other, and a triangular space is formed between the full-length horizontal stiffening plate (25), the H-shaped support (22) and the upper chord plate (311); the lower chord (1) includes a lower chord top plate (11), a lower chord bottom plate (12) and a lower chord web plate (13), and the lower chord top plate (11) and the lower chord bottom plate (12) are The lower chord web (13) is arranged relative to each other, and is vertically arranged between the lower chord top plate (11) and the lower chord bottom plate (12); the lower chord (1) also includes a lower chord stiffening plate (14), and the lower chord stiffening plate (14) is arranged between the lower chord top plate (11) and the lower chord bottom plate (12), and is arranged on both sides of the lower chord web (13); a group of vertical corbels (15) and side corbels (16) are arranged on the lower chord (1), and the lower parts of the straight web bar (4) and the oblique web bar (5) are respectively connected to the corresponding vertical corbels (15) and side corbels (16); The specific construction process is as follows: 1): Tire frame assembly. The tire frame needs to maintain its strong rigidity and the gap needs to be controlled during assembly. The tire frame template must be assembled using a special machined and planed template; 2): Check the appearance dimensions of each component before welding, and make corrections if the appearance dimensions are out of tolerance; 3): The straight web (4) and the diagonal web (5) close together; 4): The lower string (1) and the upper string (3) are made and closed; 5): Make and close the support node (2); 6): Finally, the lower chord (1), the support node (2), the upper chord (3), the straight web member (4) and the diagonal web member (5) are assembled and welded, that is, the lower chord (1) is first hoisted on the pre-assembled assembly frame for precision control; the upper chord (3) is hoisted on the pre-assembled assembly frame for precision control; secondly, the truss diagonal web member (5) is hoisted on the pre-assembled assembly frame for precision control; finally, the truss straight web member (4) is hoisted on the pre-assembled assembly frame for precision control; 7): When welding the stiffener and the connecting plate, all parts and components shall be welded in the form of T-shaped welds. The connecting groove form shall be T-shaped weld double-sided welding form. When the operating space is less than 80mm, T-shaped weld single-sided groove form shall be adopted, and the withdrawal method shall be adopted; In the step 3), during the manufacturing process of the straight web member (4) and the diagonal web member (5), both the straight web member (4) and the diagonal web member (5) are made of hot-rolled H-shaped steel, and their length is ensured during the processing, and the web member tolerance is required to be -2mm~3mm. At the same time, the bolt hole spacing accuracy of the two-port web plate needs to be controlled within -1mm~+1mmA; The specific method for making the lower string (1) and the upper string (3) in step 4) is as follows: 41): First, CP welding is used to weld the lower chord (1) and the upper chord (3) to each other, and full penetration welding is used in the node area and at 600mm on the left and right. The length tolerance of the upper chord (3) is required to be -4mm~6mm; 42): The bracket structure, the vertical bracket (15) and the side bracket (16) are welded by partial penetration welds, and the grooves at the joints are welded on both sides by T-welds; 43): The corner joint or butt joint between the H-shaped chord flange plate and the frame in the transfer node (32) and the upper chord (3) is welded by full penetration welding, and the groove at the connection between the structures is welded by root cleaning. When there is an angle in the structure, the groove is oriented in the obtuse angle direction; In step 5), the support node (2) is assembled by the positive manufacturing method. The specific manufacturing method is as follows: 51): First, the support node (2) is self-assembled, that is, the H-type support (22) is self-closed by full penetration welding, and the connection grooves of each component are welded by root cleaning; 52): Assemble and weld the support base plate (21) and the H-shaped support (22), that is, weld the support base plate (21) and the H-shaped support (22) by full penetration welding, and the groove at the connection is welded by root cleaning welding; 53): The vertical stiffener (23) is welded, and the fillet joint between the vertical stiffener (23) and the support bottom plate (21) is fixed by full penetration welding, and the connecting groove adopts the root cleaning welding groove form, and the vertical stiffener (23) and the web of the H-shaped support (22) are welded and fixed by T-shaped welding, and the connecting groove adopts the T-shaped weld double-sided welding form; 54): Install and weld the horizontal stiffener (24), the horizontal stiffener (24) and the flange plate and vertical stiffener (23) of the H-shaped support (22) are welded by full penetration welding, the groove at the connection is welded by pad welding, and the horizontal stiffener (24) and the web of the H-shaped support (22) are welded and fixed by T-shaped welds, and the groove of the connection is a T-shaped weld with a single-sided groove; 55): The fillet joint between the upper chord plate (311) in the upper chord (3) and the outer plate in the H-shaped support (22) is welded with full penetration welding, and the groove form of the connection is a root-clearing weld groove. The web plate in the H-shaped support (22) is welded and fixed by T-shaped welds, and the groove form is a T-shaped weld double-sided groove form. The fillet weld between the inner plate in the H-shaped support (22) is welded with full penetration welding, and the groove form is a pad welding form; 56): The fillet weld between the upper chord web (313) and the H-shaped support (22) is fixed by T-shaped weld welding, and the groove form of the connection is a T-shaped weld double-sided welding form; 57): The full-length horizontal stiffener (25) is welded, wherein the full-length horizontal stiffener (25) and the vertical stiffener (23) are welded by full penetration welding, and the connecting groove is a root-clearing welding groove. The full-length horizontal stiffener (25) and the inner and outer plates of the H-shaped support (22) are welded by full penetration welding, and the groove form is a pad welding groove form. The full-length horizontal stiffener (25) and the web of the H-shaped support (22) are welded by a T-shaped weld, and the groove form is a T-shaped weld single-sided groove form, and the grooves are all opened toward the lower side; 58): A plate is used to seal the triangular space formed between the full-length horizontal stiffener (25), the H-shaped support (22) and the upper chord plate (311).

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