CN114016434B - Construction method of double-arch bridge with large-span space torsion cross section - Google Patents

Abstract

A construction method for a large-span space torsion variable-section hyperbolic arch bridge belongs to the technical field of bridge construction. The arch bridge base (2) is hoisted into place; the support structure below the bridge deck is erected; the box-shaped steel beam (1) is hoisted onto the support structure section by section; the support structure above the bridge deck is erected, and an arch support (27) is arranged on the top of the support structure; the arch (3) is hoisted into place and connected section by section, and the two ends of the arch (3) are respectively welded to the corresponding sides of the arch bridge base (2); the longitudinal horizontal tie rods of the bridge deck are tensioned, and the vertical hangers (5) between the arch (3) and the bridge deck are tensioned; a steel mesh is welded on the box-shaped steel beam (1), and concrete is poured to form the bridge deck. The present invention can realize the precise positioning of the large-span arch, ensure the segmented installation construction accuracy of the torsion variable-section arch bridge, and ensure the overall construction quality of the large-span space torsion variable-section arch bridge.

Description

A construction method for a large-span spatial torsion variable-section hyperbolic arch bridge

Technical Field

The invention discloses a construction method for a large-span spatial torsion variable-section hyperbolic arch bridge, belonging to the technical field of bridge construction.

Background Art

At present, in the process of urban construction, for some steel arch bridges across rivers and lines, the arch settings are mostly regular and symmetrical, and the cross-sections of the arches are mostly regular. When the arches are installed in sections, the connection between the steel arch feet and the base is mostly made by embedding them in the concrete of the pedestal. The setting structure of the base and the pedestal is simple, and the construction positioning difficulty coefficient is small. However, when constructing a large-space torsional variable-section arch bridge with a steel structure, it is difficult to connect the steel base buried in the concrete pedestal with the special-shaped arch for construction and positioning, and the construction of the torsional variable-section arch segmented connection is difficult, and the positioning accuracy is low, which is extremely unfavorable for the quality control of the entire bridge construction. The present invention aims to solve the technical difficulties in the construction of a large-span spatial torsional variable-section arch bridge. The construction technology involved in the invention is of great significance to the quality control of the entire bridge construction.

Summary of the invention

The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a method for constructing a large-span spatial torsion variable-section hyperbolic arch bridge, which is convenient for constructing a hyperbolic arch bridge with a variable cross-section and ensures uniform stress on the hyperbolic arch and high installation accuracy.

The technical solution adopted by the present invention to solve the technical problem is: the construction method of the large-span spatial torsion variable-section hyperbolic arch bridge is characterized by comprising the following steps:

Step 1) Carry out pile foundation construction, hoist the arch bridge base into place, and pour the cap concrete;

Step 2) Construction of bridge piers and completion of the erection of supporting structures below the bridge deck;

Step 3) hoisting the box-shaped steel beams onto the bridge deck support structure section by section, and welding adjacent box-shaped steel beams to form the bridge deck;

Step 4) erecting a supporting structure above the bridge deck, and setting an arch support on the top of the supporting structure, wherein a concave limiting portion is provided on the top of the arch support;

Step 5) hoist the arches into place and connect them section by section, weld two adjacent arches, and weld the two ends of the arches to the corresponding sides of the arch bridge base;

Step 6) Install stairs at both ends of the bridge deck;

Step 7) Pull horizontal tie rods between the two ends of the arch and tension vertical hangers between the arch and the bridge deck;

Step 8) Weld the steel mesh frame on top of the box-shaped steel beam and pour concrete to form the bridge deck construction.

Preferably, a steel arch rib foundation is provided at the bottom of the arch bridge base described in step 1), and the bottom of the arch bridge base is supported on the steel arch rib foundation.

Preferably, the steel arch rib foundation includes a main body supported on the upper side of the pile foundation and a stiffening beam, the stiffening beam is arranged between the main body and the concrete cushion layer, and the stiffening beam is located between adjacent pile foundations, the arch bridge base is supported directly above the stiffening beam, and a positioning portion for positioning the arch bridge base is provided on the top of the main body.

Preferably, the support structures in step 2) are connected as a whole via inter-column pipe racks.

Preferably, in step 3), the adjacent box-shaped steel beams are leveled by a flatness control device before being welded.

Preferably, the flatness control device includes a fixed support and a leveling cone block, the fixed support and the leveling cone block are respectively connected to two adjacent box-shaped steel beams, the fixed support and the box-shaped steel beams connected thereto enclose a positioning cavity, the leveling cone block is a cone that gradually becomes thicker in the direction away from the fixed support, and the end of the leveling cone block close to the fixed support can be slidably extended into the positioning cavity.

Preferably, the box-shaped steel beams described in step 3) are installed sequentially from the middle to both ends.

Preferably, the arches described in step 5) are symmetrically arranged on both sides of the bridge deck, with both ends of each arch arranged on both sides of the bridge deck respectively, and the middle parts of the two arches intersect on the upper side of the bridge deck.

Preferably, an adjustment device is provided between the arch support and the supporting structure in step 4).

Preferably, the arches in step 5) are installed sequentially from the middle to both ends.

Compared with the prior art, the present invention has the following beneficial effects:

This large-span spatial torsion variable-section hyperbolic arch bridge construction method can achieve precise positioning of large-span arches. The limiting grooves can limit and support arches with special-shaped cross-sections, ensuring the accuracy of segmented installation construction of the torsion variable-section arch bridge and the overall construction quality of the large-span spatial torsion variable-section arch bridge.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a three-dimensional schematic diagram of a large-span spatial torsion variable-section hyperbolic arch bridge.

FIG. 2 is a left schematic diagram of the lower portion of a large-span spatial torsion variable-section hyperbolic arch bridge.

FIG. 3 is a top view schematically showing the end of a large-span spatial torsion variable-section hyperbolic arch bridge.

FIG. 4 is a three-dimensional schematic diagram of the connection between the arch and the box-shaped steel beam.

FIG. 5 is a three-dimensional schematic diagram of one end of a large-span spatial torsion variable-section hyperbolic arch bridge.

FIG. 6 is a schematic front view of the steel arch rib foundation of the arch bridge base.

FIG. 7 is a top view schematically showing the steel arch rib foundation of the arch bridge base.

FIG. 8 is a three-dimensional schematic diagram of a support frame.

FIG. 9 is a schematic front view of the support frame.

FIG. 10 is a schematic left view of the arch support frame.

Figure 11 is a node diagram of the connection between the bridge deck support frame and the arch support frame.

FIG. 12 is a perspective schematic diagram of an adjustable support.

FIG. 13 is a partial enlarged view of point A in FIG. 12 .

FIG. 14 is a three-dimensional schematic diagram of a flatness control device.

FIG. 15 is a front schematic diagram of the flatness control device in use.

In the figure: 1, box steel beam, 2, arch bridge base, 3, arch, 4, stairs, 5, vertical hanger, 6, stair support, 7, connecting frame, 8, transverse main beam, 9, longitudinal main beam, 10, stiffening beam, 11, stiffening plate, 12, positioning plate, 13, pile foundation, 14, precast foundation, 15, support frame upright, 16, support frame cross bar, 17, support frame diagonal bar, 18, bridge deck support platform, 19, support between lattice columns, 20, column, 21, cross beam, 22, diagonal brace, 23, arch support platform, 24, pipe rack between lattice columns, 25, bridge deck support frame, 26, arch support frame, 27, arch support, 28, connecting beam, 29, support plate, 30, adjustable bracket, 3001, adjustment frame, 3002, fixed frame, 31, adjustment platform, 32, fixed platform, 33, rib plate, 34, adjustment screw, 35, upper fastening nut, 36, lower fastening nut, 37, fixed support, 38, leveling cone.

DETAILED DESCRIPTION

The present invention is further described below in conjunction with specific embodiments. However, people familiar with the art should understand that the detailed description given here in conjunction with the drawings is for better explanation, and the structure of the present invention necessarily exceeds these limited embodiments. For some equivalent replacement schemes or common means, they are no longer described in detail herein, but still belong to the scope of protection of the present application.

1 to 15 are the best embodiments of the present invention, and the present invention will be further described below in conjunction with FIGS. 1 to 15 .

As shown in Figures 1 to 5: a large-span space torsion variable-section hyperbolic arch bridge includes a bridge deck, an arch bridge base 2, an arch 3 and a staircase 4. Piers are arranged on the lower sides of both ends of the bridge deck. The ends of the bridge deck and the piers are supported on the top of the piers. The piers on both sides cooperate to support the bridge deck. Staircases 4 are arranged on both sides of each end of the bridge deck. The stairs 4 are gradually inclined upward in the direction close to the bridge deck. The top of the stairs 4 is connected to the bridge deck. Staircase supports 6 are arranged at the bottom of each staircase 4. There are two arch bridge bases 2 arranged at both ends of the bridge deck. The arch bridge base 2 is arranged on the lower side of the bridge deck, the arch bridge base 2 is arranged on the inner side of the pier on the corresponding side, and the top of the arch bridge base 2 is arranged at intervals from the bridge deck. There are two arches 3 symmetrically arranged on both sides of the bridge deck. The two ends of each arch 3 are arranged on both sides of the bridge deck respectively. The middle parts of the two arches 3 intersect on the upper side of the middle part of the bridge deck, and the middle parts of the two arches 3 are arranged at intervals in the vertical direction to form a hyperbolic arch. The ends of each arch 3 are connected to the arch bridge base 2

The top of the fixed connection.

Vertical hangers 5 are arranged between the two sides of the bridge deck and the corresponding sides of the arches 3. A plurality of vertical hangers 5 are arranged side by side and at intervals along the bridge deck. A horizontal tie rod is arranged between the two ends of the two arches 3 on the same side of the bridge deck.

A connecting frame 7 is provided between the end of each arch 3 and the corresponding side of the bridge deck, one side of the connecting frame 7 is fixedly connected to the bridge deck, and the other side is fixedly connected to the corresponding arch 3. The cross section of the arch 3 is square, and each arch 3 is twisted.

The construction method of a large-span spatial torsion variable-section hyperbolic arch bridge comprises the following steps:

Step 1) Carry out pile foundation 13 construction, hoist the arch bridge base 2 into place, and pour the cap concrete.

First, the pile foundation 13 is constructed. After the pile foundation 13 meets the inspection requirements and the pile foundation 13 inspection is completed, the foundation cap is constructed. The foundation cap includes the pier foundation cap and the arch beam foundation cap. The pier is set on the pier foundation cap, and the pier is cast by concrete. When constructing the arch beam foundation cap, it should be noted that the steel arch rib foundation needs to be buried in the foundation cap in advance and the concrete is cast together.

As shown in Figures 6 and 7: The steel arch rib foundation includes a main body supported on the upper side of the pile foundation 13 and a stiffening beam 10. The stiffening beam 10 is arranged between the main body and the concrete cushion layer, and the stiffening beam 10 is located between adjacent pile foundations 13, and the stiffening beam 10 is located directly below the arch bridge base 2. The top of the main body is provided with a positioning part for positioning the arch bridge base 2. When positioning the arch bridge base 2, the bottom gap of the arch bridge base 2 can be avoided, so that the surrounding concrete is a complete whole, which fully reflects the design intention, facilitates construction, and increases the accuracy of positioning. The tool is made of steel plates and steel sections, and the manufacturing is simple.

The top of the pile foundation 13 passes through the concrete cushion layer and is set higher than the concrete cushion layer, while the bottom of the main body is elevated based on the top of the pile foundation 13. Therefore, when using the transmission construction method for construction, it is necessary to first pour concrete on the upper side of the concrete cushion layer until it is flush with the top of the pile foundation 13, and then place the main body and the arch bridge base 2 after the poured concrete solidifies, and then pour concrete outside the arch bridge base 2 again, which results in the concrete poured outside the arch bridge base 2 not being a complete whole, and the quality and the designer's intention cannot be fully guaranteed.

In this embodiment, four pile foundations 13 are provided, and the four pile foundations 13 are distributed at four vertices of a rectangle or a square.

The main body includes a transverse main beam 8 and a longitudinal main beam 9. Both the transverse main beam 8 and the longitudinal main beam 9 are made of HW400*400*13*21 steel. Two transverse main beams 8 are arranged side by side and at intervals. The longitudinal main beam 9 is arranged between the two transverse main beams 8. Two longitudinal main beams 9 are also arranged side by side and at intervals. The two ends of the longitudinal main beam 9 are respectively welded to the transverse main beam 8 on the corresponding side to form a square frame. The welding points of the ends of the longitudinal main beam 9 and the transverse main beam 8 are both located directly above the pile foundation 13 on the corresponding side. The size of the main body is determined according to the spacing of the pile foundation 13.

A stiffening plate 11 is arranged on the outside of the transverse main beam 8. Several groups of stiffening plates 11 are arranged. One group of stiffening plates 11 is arranged at both ends of each longitudinal main beam 9. Each group of stiffening plates 11 includes several plates arranged side by side and at intervals along the transverse main beam 8. In this embodiment, each group of stiffening plates 11 includes three plates arranged side by side and at intervals along the transverse main beam 8. The stiffening plates 11 are 16 mm thick steel plates.

A positioning plate 12 is arranged on the top of the main body to form a positioning portion. The positioning plate 12 is a right triangle. One right-angled side of the positioning plate 12 is parallel to the main body and welded to the top of the main body. The other right-angled side of the positioning plate 12 is arranged vertically. At least two positioning plates 12 are arranged side by side and at intervals along the longitudinal main beam 9. The steel structure bridge pier is positioned on the right-angled side of the positioning plate 12 arranged vertically. The positioning plate 12 is cut from a 20 mm thick steel plate.

The stiffening beam 10 is arranged on the lower side of the main body, and the stiffening beam 10 is located between the main body and the concrete cushion. In this embodiment, the stiffening beam 10 is arranged parallel to the longitudinal main beam 9, and a plurality of stiffening beams 10 are arranged side by side and at intervals. The stiffening beam 10 is a steel section with a model of HW100*100*6*8. The stiffening beam 10 is placed on the upper side of the concrete cushion, and the middle parts of the two transverse main beams 8 are supported on the stiffening beam 10. The stiffening beam 10 is located directly below the steel structure pier. The stiffening beam 10 can enhance the strength of the main body and prevent the middle part of the main body from bending downward after the steel structure pier is installed. The stiffening beam 10 is located between the pile foundations 13 on both sides.

The arch bridge base 2 is hoisted to the upper side of the steel arch rib foundation, and steel bars are arranged in the arch beam foundation, and then concrete is poured into the arch beam foundation.

Step 2) Construction of bridge piers and completion of the erection of supporting structures below the bridge deck.

After the construction of the abutment is completed, the bridge piers are constructed according to the design drawings, and the support frame below the bridge deck is installed according to the construction plan. According to the Tekla model, that is, the overall model of the support frame and steel components, the elevation of the support frame is strictly controlled to ensure installation accuracy.

As shown in Figures 8 to 11, the support structure includes a bridge deck support frame 25, an arch support frame 26, a bridge deck support platform 18 and an arch support 27. Several bridge deck support frames 25 are arranged side by side and at intervals. The top of at least two bridge deck support frames 25 is equipped with an arch support frame 26. The arch support frame 26 is gantry-shaped. A bridge deck support platform 18 is installed on the top of each bridge deck support frame 25. An arch support 27 for supporting the arch beam is arranged on the top of the arch support frame 26. Each bridge deck support frame 25 is installed on the prefabricated foundation 14. By setting up the arch support frame 26 on both sides of the bridge deck, a continuous whole is formed with the bridge deck support frame 25, which increases the overall stability of the frame, ensures safety during construction, and avoids the adverse effects caused by the bridge deck bearing vertical loads.

Several bridge deck support frames 25 are arranged side by side and at intervals, and each bridge deck support frame 25 is installed on the prefabricated foundation 14. Each two adjacent bridge deck support frames 25 are connected by a column-to-column pipe frame 24, and the column-to-column pipe frame 24 and the bridge deck support frame 25 are tied together by high-strength bolts. In this embodiment, ten bridge deck support frames 25 are arranged side by side and at intervals, and a bridge deck support platform 18 is arranged on the top of each bridge deck support frame 25, and the bridge deck support platform 18 is tied to the bridge deck support frame 25 by high-strength bolts.

An arch support frame 26 is arranged on the upper side of at least two bridge deck support frames 25. In this embodiment, four arch support frames 26 are arranged side by side and at intervals. The bottom of each arch support frame 26 is connected to the corresponding bridge deck support frame 25 by high-strength bolts. A grid column pipe frame 24 is arranged between each two adjacent arch support frames 26, and the grid column pipe frame 24 and the arch support frame 26 are connected by high-strength bolts. An arch support platform 23 is arranged on the top of the arch support frame 26, and two arch supports 27 are arranged side by side and at intervals on each arch support platform 23. The top of the arch support 27 is provided with a limit groove that docks with the arch 3.

The arch support frame 26 includes a lower support frame and an upper support frame. The lower support frame has two symmetrically arranged on both sides of the bridge deck support platform 18. The bottom of each lower support frame is connected to the top of the bridge deck support frame 25. The upper support frame is arranged on the upper side of the lower support frame, and the two ends of the upper support frame are respectively connected to the lower support frame on the corresponding side. The distance between the upper support frame and the bridge deck support platform 18 is 2~3m to avoid obstruction to the lifting of the bridge deck. A grid column support 19 is arranged between the two lower support frames, and the two ends of the grid column support 19 are respectively tied to the lower support frame on the corresponding side by high-strength bolts.

The bridge deck support frame 25 is a rectangular parallelepiped frame welded by support frame uprights 15 and support frame cross bars 16. A support frame diagonal bar 17 is arranged between each two adjacent support frame cross bars 16. The support frame uprights 15 are made of steel pipes of model φ245*8, and the support frame cross bars 16 and support frame diagonal bars 17 are made of steel pipes of model φ114*6. The inter-column pipe frame 24 is a connecting pipe truss welded by steel pipes of model φ114*6. The bridge deck support platform 18 is welded by steel sections of model HW300*300*10*15. The top surface of the steel section is flattened with a 20mm thick steel plate, and the steel plate is welded to the steel section.

The lower support frame of the arch support frame 26 is a rectangular parallelepiped frame welded by support frame uprights 15 and support frame crossbars 16. A support frame diagonal bar 17 is arranged between each two adjacent support frame crossbars 16. The support frame uprights 15 are made of steel pipes of model φ245*8, and the support frame crossbars 16 and support frame diagonal bars 17 are made of steel pipes of model φ114*6. The upper support frame of the arch support frame 26 is a rectangular parallelepiped frame welded by crossbeams 21 and columns 20. Diagonal braces 22 are arranged between the crossbeams 21. The columns 20 are made of steel of model HW200*200*8*12, the crossbeams 21 are made of steel of model HW300*300*10*15, and the diagonal braces 22 are made of steel of model HW150*150*7*10.

The arch support platform 23 is welded by section steel of model HW300*300*10*15, the top surface of the section steel is paved with a 20mm thick steel plate, and the steel plate is welded to the section steel.

In this step, the installation of the bridge deck support frame 25 and the bridge deck support platform 18 is completed.

Step 3) hoisting the box-shaped steel beams 1 onto the bridge deck support structure section by section, and welding and splicing adjacent box-shaped steel beams 1 to form a bridge deck.

The bridge deck support frame 25 and the bridge deck support platform 18 are installed, the elevation is checked, the installation positioning line is laid out, and after the check is correct, the installation of the bridge deck box steel beam 1 begins. According to the installed support structure, the box steel beam 1 pad is placed. When making the pad, the longitudinal slope of the box steel beam 1 is considered. According to the installation sequence of the construction plan, it is installed from the middle to the two ends. Each adjacent box steel beam 1 is welded to form a bridge deck. When the box steel beam 1 is welded, it is necessary to ensure the flatness between the adjacent box steel beams 1 to ensure the flatness of the bridge deck.

Step 4) erecting the supporting structure above the bridge deck, and setting an arch support 27 on the top of the supporting structure, and a concave limiting portion is provided on the top of the arch support 27.

An arch support frame 26 and an arch support platform 23 are set up on the upper side of the bridge deck support frame 25 and the bridge deck support platform 18 , and an arch bearing 27 is installed on the upper side of the arch support platform 23 .

As shown in Figures 12 and 13: the arch support 27 includes an adjustable support 30 and a support plate 29. The support plate 29 is located on the upper side of the adjustable support 30 and is fixedly connected to the top of the adjustable support 30. The top of the support plate 29 is provided with an inwardly concave limiting groove, and both sides of the limiting groove are gradually inclined outward from bottom to top. The limiting groove can limit the arch 3 with a special cross section and support the arch 3 with a special cross section, ensuring the accuracy of the installation of the arch 3 when the arch 3 is a twisted variable cross-section polygon, ensuring the overall construction quality of the arch bridge, and solving the problem that safety cannot be guaranteed under traditional process conditions.

The arch support 27 also includes a connecting beam 28. The arch support platform 23 is horizontally arranged. The adjustable support 30 is installed on the upper side of the arch support platform 23. The bottom of the adjustable support 30 is welded to the arch support platform 23. There are two adjustable supports 30 arranged side by side and at intervals. The two adjustable supports 30 are connected by a connecting beam 28. The two ends of the connecting beam 28 are respectively welded to the adjustable supports 30 on the corresponding side. A support plate 29 is installed on the top of each adjustable support 30. The upper side of the support plate 29 is provided with a limiting groove that matches the special-shaped cross-section arch beam. The two support plates 29 are arranged at intervals.

The arch support platform 23 is welded from steel sections, and a steel plate is welded on the top of the arch support platform 23. The adjustable support 30 includes a central column, a side column, and a support beam. The central column and the side column are both vertically arranged, and the side column has two symmetrically arranged on both sides of the central column. The lower end of the central column and the lower end of the side column are welded to the arch support platform 23, and the upper end of the central column and the upper end of the side column are welded to the support plate 29. A support beam is arranged between each side column and the central column, and one end of the support beam is welded to the side column on the corresponding side, and the other end is welded to the corresponding side of the central column.

The support plate 29 is formed by welding two steel plates, each of which has a thickness of 20 mm. The lower ends of the two steel plates are welded, and the upper ends are gradually inclined outward from bottom to top, and a "V"-shaped limiting groove with an opening facing upward is formed on the upper side of the support plate 29.

Among them, the connecting beam 28 is made of No. 18 I-steel, the supporting crossbeam is also made of No. 18 I-steel, the middle column is made of steel with model HW400*400*13*21, and the side column is made of steel with model HW250*250*9*14.

The adjustable support 30 includes an adjustment frame 3001, a fixed frame 3002 and an adjustment device. The fixed frame 3002 is arranged on the upper side of the arch support platform 23. The bottom of the fixed frame 3002 is welded to the arch support platform 23. The top of the fixed frame 3002 is welded with a fixed platform 32. The adjustment frame 3001 is arranged at intervals just above the fixed frame 3002. A horizontal adjustment platform 31 is installed at the bottom of the adjustment frame 3001. The adjustment platform 31 is arranged at intervals on the upper side of the fixed platform 32. Ribs 33 are arranged between the adjustment platform 31 and the bottom of the adjustment frame 3001 and between the fixed platform 32 and the top of the fixed frame 3002. The adjustment device is arranged between the fixed platform 32 and the adjustment platform 31. Several adjustment devices are arranged at intervals around the upper fixed platform 32. The bottom of the adjustment frame 3001 and the top of the fixed frame 3002 are both provided with connecting beams 28.

Each adjusting device includes an adjusting screw 34, an upper fastening nut 35 and a lower fastening nut 36. The adjusting screw 34 is vertically arranged. The upper end of the adjusting screw 34 extends upward after passing through the adjusting platform 31, and the adjusting screw 34 and the adjusting platform 31 can slide relatively to each other. The upper fastening nut 35 is threadedly connected to the upper part of the adjusting screw 34. There are two upper fastening nuts 35 arranged on the upper and lower sides of the adjusting platform 31. The two upper fastening nuts 35 cooperate to fasten the adjusting platform 31 and the adjusting screw 34. A gasket is arranged between each upper fastening nut 35 and the adjusting platform 31. The lower end of the adjusting screw 34 passes through the fixed platform 32 and extends downward, and the adjusting screw 34 and the fixed platform 32 can slide relative to each other. The lower fastening nut 36 is threadedly connected to the lower part of the adjusting screw 34. There are two lower fastening nuts 36 arranged on the upper and lower sides of the fixed platform 32. The two lower fastening nuts 36 cooperate to fasten the fixed platform 32 and the adjusting screw 34. A washer is arranged between each lower fastening nut 36 and the fixed platform 32.

Step 5) The arch 3 is hoisted into place and connected section by section, and two adjacent sections of the arch 3 are welded, and the two ends of the arch 3 are respectively welded to the corresponding sides of the arch bridge base 2.

The arch 3 is installed symmetrically on both sides, with the lower arch section installed first and the higher arch section installed next. After the arch 3 is installed, a connecting frame 7 is installed between the end of each arch 3 and the corresponding side of the bridge deck to connect the arch 3 to the bridge deck. At the same time, the end of each arch 3 is connected to the corresponding side of the top of the arch bridge base 2. After the arch 3 is installed, putty is scraped on the arch 3 and the bridge deck, and topcoat is sprayed.

Step 6) Install stairs 4 at both ends of the bridge deck.

Stairs 4 are installed at both ends of the bridge deck, and the bottom of the stairs 4 is supported on concrete stair supports 6.

Step 7) Tension the horizontal tie rods between the two ends of the arch 3, and tension the vertical hanger rods 5 between the arch 3 and the bridge deck.

A horizontal tie rod is tensioned between the ends of the two arches 3 on the same side of the bridge deck, that is, the two ends of the two arches on the same side of the bridge deck are connected by the horizontal tie rod.

After the arch 3 and the box-shaped steel beam 1 are all welded, the dismantling of the supporting structure begins. After the dismantling of the supporting structure, the horizontal tie rods on both sides of the box-shaped steel beam 1 are first installed and tensioned. Then the vertical suspension rods 5 between the arch 3 and the box-shaped steel beam 1 are installed and tensioned. The installation of the suspension rods is carried out symmetrically from the middle to both ends.

Vertical hangers 5 are tensioned between the arch 3 and the bridge deck. The vertical hangers 5 are tensioned symmetrically from the ends to the middle of the bridge deck, and four vertical hangers 5 are tensioned each time.

Step 8) Weld a steel mesh frame on the top of the box-shaped steel beam 1 and pour concrete to complete the bridge deck construction.

After the bridge deck base is cleaned, 20mm, 8mm, and 6mm steel bars are welded at 1m intervals on the bridge deck to ensure the slope of the bridge deck. After the bridge deck is waterproofed, φ8 steel mesh is laid with a spacing of 100mm. During the construction of stair 4, considering the inconsistent temperature deformation of steel and concrete materials and the relatively large deformation, the steel mesh is added in the steps of stair 4 and spot welded to the tread and riser.

Concrete is poured on the upper side of the bridge deck and the upper side of the stairs 4 to form the bridge deck.

As shown in FIG14 : In this embodiment, a flatness control device is used to control the flatness of adjacent box-shaped steel beams 1. The flatness control device includes a fixed support 37 and a leveling cone block 38. The fixed support 37 and the leveling cone block 38 are respectively connected to two adjacent box-shaped steel beams 1. The fixed support 37 and the box-shaped steel beam 1 connected thereto enclose a positioning cavity. The leveling cone block 38 is a cone that gradually becomes thicker in the direction away from the fixed support 37. The end of the leveling cone block 38 close to the fixed support 37 can slide into the positioning cavity. When the flatness control device is performing splicing and leveling of the box-shaped steel beam 1, it can eliminate the deformation of the steel plate caused by the production and processing of the box-shaped steel beam 1, ensure that the two box-shaped steel beams 1 remain aligned, and the operation is simple, time-saving and labor-saving, while ensuring the welding quality of the box-shaped steel beams 1 on both sides in the next stage. The tool is made of inexpensive lightweight materials, which is simple to manufacture and easy to use.

The fixed support 37 and the leveling cone block 38 are both cut from angle steel. The length of the fixed support 37 is 5-7 cm, and the length of the leveling cone block 38 is 20-25 cm. The fixed support 37 and the leveling cone block 38 are respectively welded on the two box-shaped steel beams 1 to be welded. There are several fixed supports 37 evenly spaced along the weld of the box-shaped steel beam 1. The distance between each two adjacent fixed supports 37 is 1 m. The leveling cone block 38 corresponds to the fixed support 37 one by one. The fixed support 37 can be adjusted according to the specific construction conditions.

Both sides of the fixed support 37 are tapered and gradually narrow in the direction away from the leveling cone block 38. Both sides of the fixed support 37 are connected to the box-shaped steel beam 1 on the corresponding side, and the positioning cavity is a triangular prism shape, that is, the positioning cavity is a cone with a gradually decreasing cross-sectional area in the direction away from the leveling cone block 38.

Both sides of the leveling cone block 38 are tapered gradually narrowing in the direction close to the fixed support 37, so that the leveling cone block 38 is tapered gradually thinning in the direction close to the fixed support 37. One end of the leveling cone block 38 is connected to the box steel beam 1 on the corresponding side, and the other end extends into the positioning cavity.

As shown in Figure 15: When the two box-shaped steel beams 1 are leveled, the end of the leveling cone block 38 is extended into the fixed support 37. The extrusion force of the leveling cone block 38 is used to make the two box-shaped steel beams 1 tend to be flat, which can ensure the flatness of the two box-shaped steel beams 1 after welding and the welding quality of the two box-shaped steel beams 1. In addition, the operation is simple, saving time and labor.

The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims (5)

1. A construction method for a large-span spatial torsion variable-section hyperbolic arch bridge, characterized in that it comprises the following steps: Step 1) constructing the pile foundation (13), hoisting the arch bridge base (2) into place, and pouring the cap concrete; Step 2) Construction of bridge piers and completion of the erection of supporting structures below the bridge deck; Step 3) hoisting the box-shaped steel beams (1) onto the bridge deck support structure section by section, and welding adjacent box-shaped steel beams (1) to form a bridge deck; Step 4) erecting a support structure above the bridge deck, and arranging an arch support (27) on the top of the support structure, wherein the top of the arch support (27) is provided with a concave limiting portion; the support structure comprises a bridge deck support frame (25), an arch support frame (26), a bridge deck support platform (18) and an arch support (27), wherein a plurality of bridge deck support frames (25) are arranged side by side and at intervals, and an arch support frame (26) is installed on the top of at least two bridge deck support frames (25), wherein the arch support frame (26) is gantry-shaped, and a bridge deck support platform (18) is installed on the top of each bridge deck support frame (25), and an arch support platform (23) is arranged on the top of the arch support frame (26), and two arch supports (27) are arranged side by side and at intervals on each arch support platform (23); Step 5) hoisting and connecting the arches (3) section by section, and welding two adjacent arches (3), and respectively welding the two ends of the arches (3) to the corresponding sides of the arch bridge base (2); the arch bridge base (2) is arranged on the lower side of the bridge deck, the arch bridge base (2) is arranged on the inner side of the bridge pier on the corresponding side, and the top of the arch bridge base (2) is arranged at a distance from the bridge deck, and a connecting frame (7) is arranged between the end of each arch (3) and the corresponding side of the bridge deck, one side of the connecting frame (7) is fixedly connected to the bridge deck, and the other side is fixedly connected to the arch (3) on the corresponding side; the arches (3) are symmetrically arranged on both sides of the bridge deck, and the two ends of each arch (3) are respectively arranged on both sides of the bridge deck, and the middle parts of the two arches (3) intersect on the upper side of the bridge deck; Step 6) Install stairs (4) at both ends of the bridge deck; Step 7) tensioning a horizontal tie rod between the two ends of the arch (3), and tensioning a vertical hanger rod (5) between the arch (3) and the bridge deck; Step 8) Welding a steel mesh frame on the top of the box-shaped steel beam (1) and pouring concrete to complete the bridge deck construction; In step 3), the adjacent box-shaped steel beams (1) are leveled by a flatness control device before being welded; The flatness control device comprises a fixed support (37) and a leveling cone block (38), the fixed support (37) and the leveling cone block (38) are respectively connected to two adjacent box-shaped steel beams (1), the fixed support (37) and the box-shaped steel beams (1) connected thereto enclose a positioning cavity, the leveling cone block (38) is a cone that gradually becomes thicker in a direction away from the fixed support (37), and one end of the leveling cone block (38) close to the fixed support (37) can be slidably extended into the positioning cavity; A steel arch rib foundation is arranged at the bottom of the arch bridge base (2) described in step 1), and the bottom of the arch bridge base (2) is supported on the steel arch rib foundation; in step 1), after the pile foundation (13) meets the inspection requirements and the pile foundation (13) inspection is completed, the foundation cap is constructed, and the foundation cap includes a pier foundation cap and an arch beam foundation cap. The pier is arranged on the pier foundation cap, and the pier is cast by concrete. When constructing the arch beam foundation cap, the steel arch rib foundation is buried in the foundation cap in advance and concrete is cast together; The steel arch rib foundation comprises a main body supported on the upper side of a pile foundation (13) and a stiffening beam (10), the stiffening beam (10) being arranged between the main body and the concrete cushion layer, and the stiffening beam (10) being located between adjacent pile foundations (13), the arch bridge base (2) being supported directly above the stiffening beam (10), and a positioning portion for positioning the arch bridge base (2) being arranged on the top of the main body; Four pile foundations (13) are provided, and the four pile foundations (13) are distributed at four vertices of a rectangle or a square; The main body comprises a transverse main beam (8) and a longitudinal main beam (9), two transverse main beams (8) are arranged side by side and at intervals, and the longitudinal main beam (9) is arranged between the two transverse main beams (8). Two longitudinal main beams (9) are also arranged side by side and at intervals, and both ends of the longitudinal main beam (9) are respectively welded to the transverse main beam (8) on the corresponding side to form a square frame; the welding points between the ends of the longitudinal main beam (9) and the transverse main beam (8) are both located directly above the pile foundation (13) on the corresponding side; A stiffening plate (11) is arranged on the outer side of the transverse main beam (8), and a plurality of groups of stiffening plates (11) are arranged. A group of stiffening plates (11) is correspondingly arranged at both ends of each longitudinal main beam (9), and each group of stiffening plates (11) includes a plurality of plates arranged side by side and at intervals along the transverse main beam (8); A stiffening beam (10) is arranged at the lower side of the main body, the stiffening beam (10) is located between the main body and the concrete cushion layer, the stiffening beam (10) is arranged parallel to the longitudinal main beam (9), a plurality of stiffening beams (10) are arranged side by side and at intervals, the stiffening beam (10) is placed at the upper side of the concrete cushion layer, the middle parts of the two transverse main beams (8) are supported on the stiffening beam (10), the stiffening beam (10) is located directly below the steel structure pier, and the stiffening beam (10) is located between the pile foundations (13) on both sides; The arch bridge base (2) is hoisted to the upper side of the steel arch rib foundation, and steel bars are arranged in the arch beam foundation, and then concrete is poured into the arch beam foundation. 2. The method for constructing a large-span spatial torsion variable-section hyperbolic arch bridge according to claim 1 is characterized in that: the support structures in step 2) are connected as a whole through inter-column pipe racks (24). 3. The method for constructing a large-span spatial torsional variable-section hyperbolic arch bridge according to claim 1 is characterized in that the box-shaped steel beam (1) in step 3) is installed sequentially from the middle to both ends. 4. The method for constructing a large-span spatial torsional variable-section hyperbolic arch bridge according to claim 1, characterized in that an adjustment device is provided between the arch support (27) and the supporting structure in step 4). 5. The method for constructing a large-span spatial torsion variable-section hyperbolic arch bridge according to claim 1, characterized in that the arches (3) in step 5) are installed sequentially from the middle to both ends.