High-altitude triangular cone installation and construction method based on large-span net rack starting unit assembly

Abstract

The invention discloses an installation and construction method for a high-altitude triangular pyramid based on large-span net rack starting unit assembly in the technical field of net rack construction, and the high-altitude triangular pyramid based on large-span net rack starting unit assembly comprises a gable wall net rack A, and the gable wall net rack A is installed on a concrete starting block which is poured in advance. The concrete starting block comprises a cuboid-shaped concrete block and an embedded steel plate penetrating through the center of the cuboid-shaped concrete block, the gable A-block net rack is fixedly supported on the top of the embedded steel plate, the gable A-block net rack comprises a cantilever frame and supporting frames welded to the two ends of the cantilever frame, and a rectangular space is formed by the gable A-block net rack. Through combination of block hoisting and high-altitude bulk packing, use of a large crane is reduced, the flexibility and precision of mounting of a large net rack are improved, quality control and safe construction are facilitated by adopting quadrihedron small unit splicing, the influence of foundation settlement is small, the stability of a starting unit can be enhanced through arrangement of a mooring rope and a temporary support, and the stability of the starting unit is improved. The construction safety is ensured.

Description

Technical Field

[0001] This invention relates to the field of space frame construction technology, specifically a high-altitude triangular pyramid installation construction method based on the assembly of large-span space frame starting units. Background Technology

[0002] With the development of modern construction engineering towards larger spans, larger spaces, and greater complexity, space frame structures, due to their advantages of light weight, high rigidity, and good seismic performance, are widely used in large public buildings such as stadiums, convention centers, and airport terminals. Currently, the main installation methods for large-span space frames can be divided into integral hoisting and full-span scaffolding. Integral hoisting uses large lifting equipment to lift the assembled space frame to the design elevation, suitable for small to medium-span space frames. However, because integral hoisting is limited by the rated lifting capacity and operating radius of the lifting equipment, it often requires ultra-large hoisting machinery for ultra-large spans or irregularly shaped curved space frames. Traditional full-span scaffolding provides a construction platform by erecting a ground-supported full-span system, suitable for space frames with lower heights.

[0003] However, when the span of the space frame exceeds the capacity of conventional hoisting equipment, or when the construction site is limited and large hoisting machinery cannot be arranged, the difficulty of implementing the overall hoisting plan increases significantly. In addition, pure high-altitude assembly requires all members to be spliced ​​at the design elevation, and workers need to perform a lot of positioning and welding work at high altitudes, which results in high equipment costs, poor site adaptability, low construction efficiency, and significant safety risks. For high-clearance or large-span structures, traditional scaffolding erection consumes a lot of steel and has high requirements for the stability of the support system, making it susceptible to the effects of foundation settlement. Secondly, the erection and dismantling period accounts for a large part of the total construction period, and the material turnover efficiency is low, which significantly increases the construction cost. Moreover, during the high-altitude assembly process, the cumulative error of traditional scaffolding is difficult to control, which can easily lead to quality hazards such as node misalignment and stress concentration in members. Summary of the Invention

[0004] The purpose of this invention is to provide a high-altitude triangular pyramid installation construction method based on the assembly of large-span space frame starting units, which can reduce equipment costs, improve site adaptability, effectively improve the stability of the support system, reduce the difficulty of erection and dismantling, and further reduce construction costs by improving material turnover efficiency.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A construction method for installing a high-altitude triangular pyramid based on the assembly of a large-span space frame starting unit. The high-altitude triangular pyramid based on the assembly of a large-span space frame starting unit includes a concrete starting block and a gable A block space frame. The concrete starting block includes a cuboid-shaped concrete block and a pre-embedded steel plate penetrating the center of the cuboid concrete block. The gable A block space frame is fixedly supported on the top of the pre-embedded steel plate. The gable A block space frame includes a cantilever frame and support frames welded to both ends of the cantilever frame. The gable A block space frame forms a rectangular space for supporting the roof of the space frame. The two ends of the gable A block space frame are welded to the gable B block space frame. The top of the gable A block space frame and the gable B block space frame are welded to the gable D block space frame. The two ends of the gable D block space frame and the gable B block space frame are fixed to the gable C block space frame. The top of the gable D block space frame is installed with the gable E block space frame. The top of the gable E block space frame is welded to the fixed arc-shaped gable E block space frame member. The high-altitude triangular cone installation construction method based on the assembly of large-span space frame starting units includes the following construction steps: (1) ground assembly of concrete starting blocks, (2) hoisting of component gable wall A block space frame, (3) disassembly of component gable wall B block space frame, (4) preliminary disassembly of component gable wall D block space frame, (5) disassembly of component gable wall C block space frame, (6) continued disassembly of component gable wall D block space frame, (7) preliminary disassembly of gable wall E block space frame, (8) disassembly of remaining members of gable wall D block space frame, (9) disassembly of members of gable wall E block space frame, (10) disassembly of remaining members of gable wall E block space frame, (11) initial installation of space frame, (12) disassembly assembly and installation of space frame, (13) removal of guy ropes.

[0006] As a further aspect of the present invention: the material of the embedded steel plate is steel, and the steel grade is any one of Q355, Q420 and Q460.

[0007] As a further aspect of the present invention: in step (1), when the concrete starting blocks are assembled on the ground, all concrete blocks should be installed and tightened in place at once, and if the screw holes are not up to standard, they should be repaired with a tap.

[0008] As a further solution of the present invention: In step (2), the temporary support is set at the lowest ball node of the outer guy rope binding point. Two 50-ton truck cranes are used to lift the gable wall A block grid (3) to the first target position. Based on the first target position, the verticality is adjusted by the guy rope. On the outside of the gable wall A block grid, and at the lowest ball node of the guy rope binding point, a temporary support structure is added. The support base plate and the pre-embedded parts at the top of the foundation are welded according to the design requirements. The first target position is the middle position of a horizontal row of concrete starting blocks.

[0009] As a further aspect of the present invention: In step (3), the gable wall B block space frame includes the first gable wall B block space frame and the second gable wall B block space frame. The second target position for the installation of the gable wall B block space frame is determined to be the two ends of the gable wall A block space frame. The first gable wall B block space frame and the second gable wall B block space frame are respectively arranged at one end of the gable wall A block space frame. Two 25-ton cranes are used to hoist the first gable wall B block space frame and the second gable wall B block space frame to the second target position in bulk. The verticality of the first gable wall B block space frame and the second gable wall B block space frame in actual installation is adjusted according to the second target position marked on the design drawings. The support base plate is welded to the pre-embedded parts at the top of the foundation according to the design requirements of the design drawings.

[0010] As a further aspect of the present invention: in step (4), a 25-ton crane is used to lift the D-block space frame of the gable wall in bulk to the designated position at the top of the B-block space frame of the gable wall.

[0011] As a further aspect of the present invention: in step (5), the gable C-block space frame includes a first gable C-block space frame and a second gable C-block space frame. An 80-ton crane and a 25-ton crane are used to disassemble the first gable C-block space frame and the second gable C-block space frame to the design position, adjust the angle, and weld the supports. In step (6), a 25-ton crane is used to continue to move the gable wall D block space frame to the designated position, and the steel wire is tensioned to tighten the contact point between the gable wall D block space frame and the space frame at the designated position.

[0012] As a further aspect of the present invention: in step (7), a 25-ton crane is used to disassemble the gable wall E block space frame to the designated position, and the disassembly position of the gable wall E block space frame is the top of the gable wall D block space frame; in step (8), a 50-ton crane is used to disassemble the remaining members of the gable wall D block space frame to the corresponding design position.

[0013] As a further aspect of the present invention: in step (9), a 50-ton crane is used to disassemble the gable wall E block space frame members to the corresponding design positions.

[0014] As a further aspect of the present invention: in step (10), a 50-ton crane is used to disassemble the remaining gable wall E block space frame members to the corresponding design positions to complete the installation process of the space frame starting unit; in step (11), binding points are set at multiple locations of the starting unit, and gable wall guy ropes are used to bind and connect the space frame at the binding points.

[0015] As a further aspect of the present invention: In step (12), a 50-ton crane is used for high-altitude assembly of small assembly units. The small assembly unit is a triangular pyramid, including a node ball and three to four rods. Depending on the installation position, the triangular pyramid is set as an upper chord triangular pyramid and a lower chord triangular pyramid. The upper chord triangular pyramid and the lower chord triangular pyramid are installed in sequence until the starting unit of the space frame forms a stable structure. The installation personnel are divided into a ground assembly group and a high-altitude installation group. The ground assembly group assembles the small units according to the drawings, and the high-altitude installation group completes the connection between the small units and the structure. During high-altitude installation, the high-strength bolts should be initially tightened and then finally tightened. The tightening sequence is to press first and then pull, to avoid local areas being tightened first. In step (13), after the starting unit of the space frame is assembled for 3-5 column spacings, the guy ropes are removed.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention effectively reduces the use of large cranes by combining segmented hoisting with high-altitude bulk assembly, greatly improving the flexibility and precision of installing large space frames and increasing construction efficiency. At the same time, the use of triangular pyramid small unit assembly facilitates quality control and safe construction, and is less affected by foundation settlement. The setting of guy ropes and temporary supports can enhance the stability of the starting unit and ensure construction safety. Attached Figure Description

[0017] Figure 1 This is a schematic diagram illustrating the hoisting process of the gable wall A-block space frame of the present invention; Figure 2 This is a schematic diagram of the hoisting and positioning of the gable wall A-block space frame of the present invention; Figure 3 This is a schematic diagram of the hoisting process of the B-block space frame of the gable wall according to the present invention; Figure 4 This is a schematic diagram of the hoisting and positioning of the B-block space frame of the gable wall according to the present invention; Figure 5 This is a schematic diagram of the initial hoisting and positioning of the D-block space frame of the gable wall according to the present invention; Figure 6 This is a schematic diagram illustrating the continued hoisting process of the C-block space frame of the gable wall according to the present invention; Figure 7 This is a schematic diagram illustrating the continued hoisting and positioning of the D-block space frame of the gable wall according to the present invention; Figure 8 This is a schematic diagram of the bulk assembly process of the E-block space frame of the gable wall according to the present invention; Figure 9 This is a diagram illustrating the assembly process of the remaining structural members of the E-block space frame of the gable wall according to the present invention. Figure 10 This is a schematic diagram of the assembly process of the gable wall E-block space frame members of the present invention; Figure 11 This is a schematic diagram of the placement process of the space frame members of the E block of the gable wall according to the present invention; Figure 12This is a schematic diagram of the installation and positioning of the space frame starting unit of the present invention; Figure 13 This is a schematic diagram of the guy rope binding points for the gable wall of the coal storage yard at axes 36-35, according to a specific embodiment of the present invention.

[0018] In the diagram: 1. Concrete block; 2. Embedded steel plate; 3. Gable wall A block space frame; 4. First gable wall B block space frame; 5. Second gable wall B block space frame; 6. Gable wall D block space frame; 7. First gable wall C block space frame; 8. Second gable wall C block space frame; 9. Gable wall E block space frame; 10. Gable wall E block space frame members. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example: Please see Figures 1-13 In this embodiment, a method for installing a high-altitude triangular pyramid based on the assembly of a large-span space frame starting unit is disclosed. The high-altitude triangular pyramid based on the assembly of a large-span space frame starting unit includes a concrete starting block and a gable wall A block space frame 3. The concrete starting block includes a cuboid concrete block 1 and a pre-embedded steel plate 2 penetrating the center of the cuboid concrete block. The gable wall A block space frame 3 is fixedly supported on the top of the pre-embedded steel plate 2. The gable wall A block space frame 3 includes a cantilever frame and a support frame welded to both ends of the cantilever frame. The gable wall A block space frame 3 forms a rectangular space for supporting the roof of the space frame. The two ends of the gable wall A block space frame 3 are welded to the gable wall B block space frame. The top of the gable wall A block space frame 3 and the gable wall B block space frame are welded to the gable wall D block space frame 6. The two ends of the gable wall D block space frame 6 and the gable wall B block space frame are fixed to the gable wall C block space frame. The top of the gable wall D block space frame 6 is installed with the gable wall E block space frame 9. The top of the gable wall E block space frame 9 is welded to the top of the arc-shaped gable wall E block space frame member 10. The high-altitude triangular pyramid installation construction method based on the assembly of large-span space frame starting units includes the following construction steps: (1) ground assembly of concrete starting blocks, (2) hoisting of component gable wall A block space frame, (3) disassembly of component gable wall B block space frame, (4) preliminary disassembly of component gable wall D block space frame, (5) disassembly of component gable wall C block space frame, (6) continued disassembly of component gable wall D block space frame, (7) preliminary disassembly of gable wall E block space frame, (8) disassembly of remaining members of gable wall D block space frame, (9) disassembly of members of gable wall E block space frame, (10) disassembly of remaining members of gable wall E block space frame, (11) initial installation of space frame, (12) disassembly assembly and installation of space frame, (13) removal of guy ropes.

[0021] In this embodiment, the material of the embedded steel plate 2 is steel, and the steel grade is any one of Q355, Q420 and Q460.

[0022] Preferred, such as Figure 1 As shown, in step (1), when the concrete starting blocks are assembled on the ground, all concrete blocks 1 should be installed and tightened in place at one time, and the screw holes should be repaired with a tap if they are not qualified.

[0023] Preferred, such as Figure 3 As shown, in step (2), the temporary support is set at the lowest ball node of the outer guy rope binding point. Two 50-ton truck cranes are used to lift the gable wall A block space frame 3 to the first target position. Based on the first target position, the verticality is adjusted by the guy rope. On the outside of the gable wall A block space frame, and at the lowest ball node of the guy rope binding point, a temporary support structure is added. The support base plate and the pre-embedded parts at the top of the foundation are welded according to the design requirements. The first target position is the middle position of a horizontal row of concrete starting blocks.

[0024] Preferred, such as Figure 3 As shown, in step (3), the gable wall B block space frame includes the first gable wall B block space frame 4 and the second gable wall B block space frame 5. The second target position for the installation of the gable wall B block space frame is determined to be the two ends of the gable wall A block space frame 3. The first gable wall B block space frame 4 and the second gable wall B block space frame 5 are respectively arranged at one end of the gable wall A block space frame 3. Two 25-ton cranes are used to lift the first gable wall B block space frame 4 and the second gable wall B block space frame 5 to the second target position in bulk. The verticality of the first gable wall B block space frame 4 and the second gable wall B block space frame 5 in actual installation is adjusted according to the second target position marked on the design drawings. The support base plate is welded to the pre-embedded parts at the top of the foundation according to the design requirements of the design drawings.

[0025] Preferred, such as Figure 5 As shown, in step (4), a 25-ton crane is used to lift the D-block space frame 6 of the gable wall to the designated position at the top of the B-block space frame of the gable wall.

[0026] Preferred, such as Figure 6 As shown, in step (5), the gable C block space frame includes the first gable C block space frame 7 and the second gable C block space frame 8. The first gable C block space frame 7 and the second gable C block space frame 8 are disassembled to the design position using an 80-ton crane and a 25-ton crane, respectively. The angle is adjusted and the supports are welded. In step (6), a 25-ton crane is used to continue to move the gable wall D block space frame 6 to the designated position, and the steel wire is tensioned to tighten the contact point between the gable wall D block space frame 6 and the space frame at the designated position.

[0027] Preferred, such as Figure 8As shown, in step (7), a 25-ton crane is used to disassemble the E-block space frame 9 of the gable wall to the designated position. The disassembly position of the E-block space frame 9 of the gable wall is the top of the D-block space frame 6 of the gable wall. In step (8), a 50-ton crane is used to disassemble the remaining members of the D-block space frame 6 of the gable wall to the corresponding design position.

[0028] Preferred, such as Figure 10 As shown, in step (9), a 50-ton crane is used to disassemble the space frame members 10 of the gable wall E block to the corresponding design position.

[0029] Preferred, such as Figure 11 As shown, in step (10), a 50-ton crane is used to disassemble the remaining gable wall E block space frame members 10 to the corresponding design positions to complete the installation process of the space frame starting unit; in step 11, binding points are set at multiple locations of the starting unit, and gable wall guy ropes are used to bind and connect the space frame at the binding points.

[0030] In step 12, a 50-ton crane is used for high-altitude assembly of small modular units. Each small modular unit is a triangular pyramid, consisting of a node ball and three to four rods. Depending on the installation location, the triangular pyramid is configured as an upper chord triangular pyramid and a lower chord triangular pyramid. The upper chord triangular pyramid and the lower chord triangular pyramid are installed sequentially until the starting unit of the space frame forms a stable structure. The installation personnel are divided into a ground assembly group and a high-altitude installation group. The ground assembly group assembles the small units according to the drawings, while the high-altitude installation group completes the connection between the small units and the structure. During high-altitude installation, high-strength bolts should be initially tightened and then finally tightened, with the tightening sequence being pressure first and then tension, to avoid localized premature tightening.

[0031] In this embodiment, during high-altitude assembly, the installation personnel on each work surface can be divided into two parts: one part assembles small units, and the other part performs high-altitude installation. The installation procedure is as follows: first, the ground assembly personnel assemble the small units of the space frame to be installed on the ground according to the drawings; then, a crane is used to lift the small units to the corresponding installation positions in the air, and the high-altitude workers complete the connection between the small units and the structure.

[0032] In step (12), the ground unit is also called a triangular pyramid, which is a small unit assembled on the ground by a node ball and three to four rods. The small unit is divided into a lower chord unit and an upper chord unit. When assembling on the ground, all rods should be installed and tightened in place at one time. If there are screw holes that are difficult to install, a tap should be used to repair the screw holes to meet the requirements before installation. In step (12), the installation of the small unit includes using a crane to lift the small unit to the installation location. At each connection point, an installer is on-site at high altitude to receive the unit. After receiving the corresponding installation rod, the installer connects the high-strength studs to the bolt ball holes. During the installation of the space frame, the high-strength bolts should be tightened to the correct position. No gaps visible to the naked eye are allowed on the contact surface of the threadless nut. Tightening should be done with a wrench, with initial tightening and final tightening. The tightening sequence is to press first and then pull to prevent the rod from being locked and the bolts from being loose. During the initial connection, three to five turns should be tightened first. Depending on the installation situation of other installers, after all the installation studs have entered the stud ball, the high-strength studs should be tightened to the correct position together. It is important to avoid tightening one or two high-strength bolts first, as this will make it difficult to install the other high-strength bolts in place.

[0033] In step (13), after the space frame starting unit has been assembled into 3-5 column spacings, the guy ropes are removed.

[0034] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A high-altitude triangular pyramid installation construction method based on large-span net frame starting unit assembly, characterized in that, The high-altitude triangular pyramid based on the assembling of the starting unit of the large-span net rack comprises a concrete starting block and a gable A block net rack, the gable A block net rack is installed on the pre-cast concrete starting block, the concrete starting block comprises a cuboid concrete block and a pre-embedded steel plate penetrating through the center of the cuboid concrete block, the gable A block net rack is fixedly supported on the top of the pre-embedded steel plate, the gable A block net rack comprises a cantilever frame and support frames welded at both ends of the cantilever frame, the gable A block net rack forms a rectangular space for supporting the roof of the net rack, gable B block net racks are welded at both ends of the gable A block net rack, gable D block net racks are welded at the top of the gable A block net rack and the gable B block net rack, gable C block net racks are fixed at both ends of the gable D block net rack, gable E block net racks are installed at the top of the gable D block net rack, and arc-shaped gable E block net rack members are welded and fixed at the top of the gable E block net rack; The installation construction method of the high-altitude triangular pyramid based on the assembling of the starting unit of the large-span net rack comprises the following construction steps: (1) ground assembling of the concrete starting block, (2) hoisting of the component gable A block net rack, (3) scattering of the component gable B block net rack, (4) preliminary scattering of the component gable D block net rack, (5) scattering of the component gable C block net rack, (6) continued scattering of the component gable D block net rack, (7) preliminary scattering of the gable E block net rack, (8) scattering of the remaining members of the gable D block net rack, (9) scattering of the members of the gable E block net rack, (10) scattering of the remaining members of the gable E block net rack, (11) starting installation of the net rack, (12) scattering and assembling installation of the net rack, and (13) removal of the cable wind rope.

2. The high-altitude triangular pyramid installation construction method based on the large-span net rack starting unit assembly according to claim 1, characterized in that: In step (1), when the concrete starting block is assembled on the ground, all the concrete blocks should be installed and fastened in place at one time, and a screw hole that is unqualified is adjusted by using a screw tap.

3. The high-altitude triangular pyramid installation construction method based on the large-span net rack starting unit assembly according to claim 1, characterized in that: In step (2), a temporary support is arranged at the lowermost ball node of the outer cable wind rope binding point, the gable A block net rack (3) is hoisted to the first target position by using two 50-ton truck cranes, the verticality is adjusted based on the first target position, a temporary support structure is additionally arranged outside the gable A block net rack and at the lowermost ball node of the cable wind rope binding point, the support base plate and the top pre-embedded part of the foundation are welded according to the design requirements, and the first target position is the middle position of one row of concrete starting blocks.

4. The high-altitude triangular pyramid installation construction method based on the large-span net rack starting unit assembly according to claim 1, characterized in that: In step (3), the gable B block net rack comprises a first gable B block net rack and a second gable B block net rack, the second target position of the gable B block net rack installation is determined to be at both ends of the gable A block net rack, the first gable B block net rack and the second gable B block net rack are arranged at one end of the gable A block net rack respectively, the first gable B block net rack and the second gable B block net rack are scattered and hoisted to the second target position by using two 25-ton cranes, the verticality of the first gable B block net rack and the second gable B block net rack in the actual installation is adjusted according to the second target position marked on the design drawing, and the support base plate and the top pre-embedded part of the foundation are welded according to the design requirements of the design drawing.

5. The high-altitude triangular pyramid installation construction method based on the large-span net rack starting unit assembly according to claim 1, characterized in that: In step (4), the gable D block net rack is scattered and hoisted to the specified position at the top of the gable B block net rack by using a 25-ton crane.

6. The high-altitude triangular pyramid installation construction method based on the large-span net rack starting unit assembly according to claim 3, characterized in that: In step (5), the gable C block truss includes a first gable C block truss and a second gable C block truss, and the first gable C block truss and the second gable C block truss are respectively bulked to the designed position using an 80-ton crane and a 25-ton crane, the angle is adjusted, and the support is welded; In step (6), the 25-ton crane is used to continue to bulk the gable D block truss to the designated position, and the steel wire is tensioned to tighten the gable D block truss and the truss at the contact position of the designated position.

7. The high-altitude triangular pyramid installation construction method based on the large-span net rack starting unit assembly according to claim 1, characterized in that: In step (7), the 25-ton crane is used to bulk the gable E block truss to the designated position, and the bulk position of the gable E block truss is the top of the gable D block truss; in step (8), the 50-ton crane is used to bulk the remaining rod of the gable D block truss to the corresponding designed position.

8. The high-altitude triangular pyramid installation construction method based on the large-span net rack starting unit assembly according to claim 1, characterized in that: In step (9), the 50-ton crane is used to bulk the gable E block truss rod to the corresponding designed position.

9. The high-altitude triangular pyramid installation construction method based on the large-span net rack starting unit assembly according to claim 1, characterized in that: In step (10), the 50-ton crane is used to bulk the remaining gable E block truss rod to the corresponding designed position, and the installation process of the starting unit of the truss is completed; in step (11), the binding points are arranged at multiple positions of the starting unit, and the truss at the binding point is bound and connected using the gable cable wind rope.

10. The high-altitude triangular pyramid installation construction method based on the large-span net rack starting unit assembly according to claim 1, characterized in that: In step (12), the 50-ton crane is used for high-altitude bulk of small splicing units, the small splicing unit is a triangular pyramid including one node ball and three to four rods, the triangular pyramid is set as an upper chord triangular pyramid and a lower chord triangular pyramid according to different installation positions, the upper chord triangular pyramid and the lower chord triangular pyramid are installed in sequence until the starting unit of the truss forms a stable structure, the installation personnel are divided into a ground assembling group and a high-altitude installation group, the ground assembling group assembles the small unit according to the drawing, and the high-altitude installation group completes the connection of the small unit and the structure, when the high-altitude installation is performed, the high-strength bolt should be initially screwed and finally screwed, the tightening order is pressing first and pulling second, and local tightness is avoided; in step (13), when the starting unit of the truss is bulked for 3-5 column distances, the cable wind rope is removed.

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