Construction method for steel-concrete combined section of steel-concrete mixed rigid framework

Abstract

The invention belongs to the technical field of bridge construction, and particularly relates to a construction method for a steel-concrete combined section of a steel-concrete mixed rigid frame. During construction of the maximum concrete cantilever end, preformed holes and embedded parts for construction of the steel-concrete combined section are embedded; a hanging basket is modified, a hanging bracket system is installed, and steel-concrete interface reinforcing steel bar pre-bending and prestressed steel strand adduction treatment are conducted at the same time; a steel-concrete combined section bridge site is in place, a lifting appliance system is installed on a ship surface, and lifting steel strands are pre-tightened; hoisting points are subjected to trial hoisting and formal hoisting after being longitudinally and transversely adjusted through a hoisting frame system, and slow-setting prestressed tendons penetrate and longitudinal reinforcing steel bars at flanges are connected before the hoisting points are in place; after the longitudinal movement is in place, the steel-concrete combined section and the connecting embedded part are locked, a prestressed steel strand penetrates, and a steel bar and a formwork system are installed; pre-tensioning partial prestressed steel strands and installing a cantilever beam system; the hanging bracket system main body and the cantilever beam hanging strap are modified by utilizing an original hanging basket, so that the assembly and disassembly efficiency is high.

Description

Technical Field

[0001] This invention belongs to the field of bridge construction technology, specifically relating to a construction method for a steel-concrete hybrid rigid frame steel-concrete composite section. Background Technology

[0002] The steel-concrete interface section is the core component where the steel and concrete structures work together to bear loads, and its interface performance directly determines the safety and durability of the overall structure. As key components for transmitting shear force, axial force, and bending moment, the embedded parts at the steel-concrete interface are crucial for ensuring a reliable connection and coordinated operation between the two materials. Their design, processing, and installation quality are of paramount importance to the performance of the interface section.

[0003] Currently, the main method for cantilever erection of steel-concrete composite sections is to use lifting equipment and pre-embedded parts at the steel-concrete interface to transfer loads. However, most lifting equipment involves removing the existing formwork from the cantilevered concrete segment and installing a bridge deck crane. Furthermore, adjusting the balance of the lifting system during the erection of the steel-concrete composite section and adjusting the longitudinal and transverse movement system for its positioning are relatively difficult. This method is time-consuming, inefficient, and requires re-processing of relevant procedures, which significantly impacts the construction schedule. Currently, the method of pre-embedded parts at the steel-concrete interface to transfer loads is subject to the influence of high-altitude operations and welding surfaces. The quality of the pre-embedded parts and welding may not meet the expected requirements. It is easy for the weld of the pre-embedded parts to fail due to excessive self-weight during the concrete pouring of the steel-concrete interface section. Furthermore, the excessive self-weight, with the top hoisting equipment connecting the top plate of the steel-concrete interface section and the end pre-embedded parts connecting the web and bottom plate of the steel-concrete interface section, can easily cause significant deformation of the steel beams, affecting the installation of the subsequent standard section steel beams. In some cases, it can even lead to cracks in the concrete at the steel-concrete interface.

[0004] Based on this, in order to improve construction efficiency while ensuring construction quality, a construction method for steel-concrete hybrid rigid frame steel-concrete composite section is proposed. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, this invention provides a construction method for a steel-concrete hybrid rigid frame steel-concrete composite section.

[0006] The objective of this invention can be achieved through the following technical solutions: A construction method for a steel-concrete hybrid rigid frame steel-concrete composite section includes the following steps: S1: Construction of the largest concrete cantilever end, during which pre-embedded holes and pre-embedded parts are used for the construction of the steel-concrete composite section. S2: Modify the hanging basket, install the hanging system, and simultaneously perform pre-bending of the steel-concrete interface reinforcement and inward treatment of the prestressed steel strands; S3: The steel-concrete composite section of the bridge site is in place, the lifting system is installed on the deck and the steel strands are pre-tightened during lifting; S4: After the lifting points are adjusted longitudinally and laterally by the lifting system, trial lifting and formal lifting are carried out. Before positioning, the slow-setting prestressed tendons are inserted and the longitudinal steel bars at the flange are connected. S5: After longitudinal movement and positioning, the steel-concrete composite section is locked with the connecting embedded parts, the prestressed steel strands are threaded, and the reinforcing bars and formwork system are installed. S6: Partial prestressed steel strand pretensioning and cantilever beam system installation; S7: Concrete pouring and tensioning of prestressed steel strands.

[0007] As a further embodiment of the present invention, in step S1, the reserved holes include anchor holes for the track pressure beam of the hanger system, anchor holes for the rear anchor pressure beam of the hanger system, and anchor holes for the rear anchor pressure beam of the cantilever beam system. The embedded parts include embedded parts for the cantilever beam of the cantilever beam system and embedded parts for connecting the end sections of the cantilever concrete beam segment.

[0008] As a further aspect of the present invention, in step S2, the modified hanging basket is moved forward after the last cantilevered concrete beam segment is completed, and then the side formwork of the hanging basket and the hanging basket hoisting system are lowered to the barge below by a winch; the installation of the hoisting system specifically involves installing a transverse support on the upper crossbeam of the modified hanging basket, and installing a hydraulic continuous jack and a longitudinal and transverse sliding device on it; then the lower construction platform is installed, and the pre-numbered hoisting steel strands A and B are respectively threaded into hydraulic continuous jacks A and B.

[0009] As a further embodiment of the present invention, in step S2, before hoisting the steel-concrete composite section, the beam end section needs to be accurately measured and laid out. Based on the layout results, the composite surface is roughened, and the steel-concrete interface steel bars are pre-bent into the box-type structure at a certain angle. Then, the prestressed steel strands are bundled and then pulled into the box-type structure.

[0010] As a further aspect of the present invention, in step S3, the steel-concrete composite section is transported to the bridge site by ship. On the ship deck, the lifting system is first connected to the first lifting lug of the top plate of the steel-concrete composite section. Then, the steel strands A and B suspended by the lifting system are threaded into the lifting connection seat, and each hoisting steel strand is pre-tightened on the lowered construction platform.

[0011] As a further aspect of the present invention, in step S4, the longitudinal and transverse positions are first determined by the upper crossbeam push-pull rod and the transverse fine-adjustment screw jack on the lifting system. Then, in order to determine the balance state of the steel-concrete composite section during hoisting, the lifting tool push-pull rod on the lifting tool system is adjusted. After the adjustment is completed, a trial hoisting and formal hoisting are carried out. After hoisting to a certain distance from the design elevation, the slow-setting prestressing tendons of the cantilever concrete beam section are first inserted into the flange of the steel-concrete composite section. When hoisting to the design elevation, the longitudinal steel bars reserved in the cantilever concrete beam section are connected to the longitudinal steel bars pre-installed in the flange of the steel-concrete composite section.

[0012] As a further aspect of the present invention, in step S5, the steel-concrete composite section is positioned by retracting the upper crossbeam push-pull rod of the hanger system. After fine adjustment, its web plate is welded and locked to the connecting embedded parts. Then, the prestressed steel strands of the cantilevered concrete beam section are inserted into the prestressed ducts of the steel-concrete composite section, and the reinforcement and formwork system are installed simultaneously. The cantilever beam system is also hoisted onto the bridge and roughly positioned simultaneously.

[0013] As a further aspect of the present invention, in step S6, in order to counteract the tension of the embedded parts connecting the upper web of the steel-concrete composite section during concrete pouring and control the bending moment, some prestressed steel strands are pre-tensioned before the cantilever beam system is fixed. After tensioning, the cantilever beam system is connected to the top and bottom plates of the steel-concrete composite section, and the front support points are pre-filled to allow the cantilever beam to bear the force in advance.

[0014] As a further aspect of the present invention, in step S7, the concrete is poured in layers of equal strength, the prestressed steel strands are tensioned, and the cantilever beam system is dismantled.

[0015] The beneficial effects of this invention are as follows: (1) The main body of the hanging system and the cantilever beam hanging sling of the present invention are modified from the original hanging basket, which has high assembly and disassembly efficiency; (2) The lifting system and lifting tools can be used with push-pull rods to adapt to the subsequent lifting of various segments, improve the stability during lifting and avoid the influence of the concrete cantilever end reinforcement, effectively increasing the safety and efficiency of the lifting process; (3) The dual protection of embedded parts and cantilever beam system makes the load-bearing of concrete in the steel-concrete composite section safer and more reliable, which can provide a reference for the construction of steel-concrete composite section. Attached Figure Description

[0016] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0017] Appendix Figure 1 This is a side view of the hoisting of the steel-concrete composite section; Appendix Figure 2 This is a schematic diagram of the hoisting elevation of the steel-concrete composite section; Appendix Figure 3 This is a side view of the steel-concrete composite section after the concrete pouring is completed. Appendix Figure 4 A schematic diagram of a side explosion after the concrete pouring of the steel-concrete composite section is completed; Appendix Figure 5 This is a side view of the cantilever beam system in the steel-concrete composite section; Appendix Figure 6 This is a schematic elevation view of the cantilever beam system in the steel-concrete composite section; Appendix Figure 7 A side view of the embedded parts and prestressed steel strands in the steel-concrete composite section; Appendix Figure 8 A schematic diagram of the elevation of the embedded parts and prestressed steel strands in the steel-concrete composite section; Appendix Figure 9 A side view of the concrete pouring for the partition plate of the steel-concrete composite section; Appendix Figure 10 A schematic diagram of the concrete roof slab pouring for the steel-concrete composite section; Explanation of reference numerals in the attached diagram: 1. Hanging system; 101. Main truss of the hanging basket; 102. Front upper crossbeam A; 103. Front upper crossbeam B; 104. Continuous jack A; 105. Continuous jack B; 106. Lateral support; 107. Push-pull rod reaction seat; 108. Upper crossbeam push-pull rod; 109. Lateral reaction seat; 110. Lateral fine-tuning screw jack; 111. Steel strand A; 112. Steel strand B; 2. Lifting device system; 201. Lifting device connecting seat; 202. Lifting device conversion seat; 203. Lifting device spreader beam; 204. Lifting device sling; 205. First lifting lug; 206. Lifting device push-pull rod; 207. Precision rolled threaded steel; 20 8. Bolts; 3. Connecting embedded parts; 4. Cantilevered concrete beam segment; 5. Steel-concrete composite segment; 6. Cantilever beam system; 601. Cantilever beam; 602. Cantilever beam embedded parts; 603. Cantilever beam rear anchor; 604. Hanging crossbeam; 605. Spiral jack; 606. Hanging strap; 607. Second lifting lug; 608. Stiffening plate; 7. Concrete; 8. Prestressed steel strand; 9. Formwork system; 901. Disc-lock scaffold; 902. Longitudinal limiting of channel steel; 903. Wooden formwork; 904. Tie rod threaded steel; 905. Channel steel attachment; 906. Reinforcing bar support; 10. Material unloading frame; 11. Lowering construction platform; 12. Slow-setting prestressed tendons. Detailed Implementation

[0018] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided.

[0019] This embodiment discloses a construction method for a steel-concrete hybrid rigid structure steel-concrete composite section.

[0020] like Figures 1-10 As shown, the construction method for the steel-concrete composite rigid frame steel-concrete joint section includes the following steps: S1: During the construction of the last cantilevered concrete beam segment 4, after precise measurement, PVC pipes were used to pre-embed the track pressure beam anchoring holes of the hanger system 1, the rear anchor pressure beam anchoring holes of the hanger system 1, and the rear anchor pressure beam anchoring holes of the cantilever beam system 6. The verticality was strictly controlled during the pre-embedding process. At the same time, the cantilever beam pre-embedded part 602 of the cantilever beam system 6 and the connecting pre-embedded part 3 on the end section of the cantilevered concrete beam segment 4 were pre-embedded. The elevation of the cantilever beam pre-embedded part 602 was strictly controlled to ensure the connection of the pin shaft between the cantilever beam system 6 and the steel-concrete composite section 5. The mileage coordinate of the connecting pre-embedded part 3 along the bridge direction was strictly controlled to ensure that the section of the cantilevered concrete beam segment 4 and the steel-concrete composite section 5 fit closely together.

[0021] S21: After the last cantilevered concrete beam segment 4 is completed and the formwork is moved forward, the formwork is modified to form a suspension system 1, retaining the main truss 101, front upper crossbeam A102, and front upper crossbeam B103. The front upper crossbeams A102 and B103 were designed with the reinforcement and openings required for the hoisting of the steel-concrete composite segment 5 in mind before the initial installation of the formwork on the cantilevered concrete beam segment 4. Polytetrafluoroethylene (PTFE) sliding plates are installed between the front upper crossbeams A102 and B103 and the upper chord of the main truss 101 to form the subsequent longitudinal movement system. The modification process involves first lowering the dismantled inner formwork and sliding beams to the barge below using a truck crane on the bridge deck. Then, multiple winches fixed to the bridge deck work together to lower the side and bottom formwork of the formwork to the barge below. Finally, the formwork suspension system is dismantled and placed on the bridge deck for use as subsequent hoisting straps 606.

[0022] S22: After the excess components are lowered, the front upper crossbeam A102 and the front upper crossbeam B103 are connected by steel sections. The steel sections are parallel to the upper chord of the main truss 101 of the hanging basket. Then, push-pull rod reaction seat 107 is welded at the end node of the upper chord of the main truss 101 of the hanging basket. The push-pull rod reaction seat 107 is connected to the front upper crossbeam B103 through the upper crossbeam push-pull rod 108. The upper crossbeam push-pull rod 108 is set on each side of the main truss 101 of the hanging basket and should meet the longitudinal movement requirements of the largest segment.

[0023] S23: A transverse support 106 is installed on the front upper crossbeam A102 and the front upper crossbeam B103. The transverse support 106 is fastened to the upper flange of the front upper crossbeam A102 and the front upper crossbeam B103 by a buckle to prevent overturning. A polytetrafluoroethylene plate is provided between the upper flange of the crossbeam and the bottom of the transverse support 106. A transverse reaction seat 109 is welded on each side of each transverse support 106. A transverse fine-tuning screw jack 110 is installed between the transverse support 106 and the transverse reaction seat 109. The transverse system is formed by the transverse fine-tuning screw jack 110 and the polytetrafluoroethylene plate.

[0024] S24: Subsequently, hydraulic continuous jacks will be installed on the transverse support 106. The hydraulic continuous jacks are divided into continuous jacks A104 for the main hoist and continuous jacks B105 for attitude adjustment. The continuous jacks A104 for the main hoist must be designed to independently bear the entire weight of the steel-concrete composite section 5. The hydraulic continuous jacks are welded and fixed to the top plate of the transverse support 106 via a "7"-shaped plate. At the same time, the lowering construction platform 11 is installed, and the hoisting steel strands A111 and B112 are numbered with the anchor holes of the jacks. Subsequently, they are inserted into the hydraulic continuous jacks B105 through the lowering construction platform 11. The lower ends of steel strands A111 and B112 are suspended to the upper end of the subsequent steel-concrete composite section 5. The upper ends of the steel strands are guided to both sides of the cantilevered concrete beam section 4 through the lowering construction platform 11. During the subsequent lifting process, steel strands A111 and B112 are lowered down the bridge along both sides of the cantilevered concrete beam section 4.

[0025] S25: During the process of modifying the hanging basket, the beam end section is accurately measured and laid out. Based on the layout results, the joint surface is roughened and the steel-concrete interface steel bars are pre-bent into the box at a certain angle. The projected length after pre-bending should not affect the vertical lifting of the steel-concrete joint section 5. Then, the prestressed steel strands 8 are bundled and then pulled into the box chamber.

[0026] S31: The steel-concrete composite section 5 is transported to the bridge site by ship. On the ship deck, the lifting system 2 is first connected as a whole by the lifting connecting seat 201, the lifting conversion seat 202, the lifting spreader beam 203 and the lifting strap 204. Then, the lifting system 2 is connected to the first lifting lug 205 of the top plate of the steel-concrete composite section 5 by a truck crane through a pin shaft.

[0027] S32: Insert the steel strands A111 and B112 suspended from the hanger system 1 into the lifting device connecting seat 201, and pre-tighten each hoisting steel strand on the lowering construction platform 11 on the hanger system 1. The pre-tightening standard is to ensure that each hoisting steel strand is subjected to uniform force.

[0028] S41: First, adjust and determine the longitudinal position of the hoisting by using the upper crossbeam push-pull rod 108 on the hoisting system 1. The position is a certain distance away from the cantilevered concrete beam segment 4, and the distance is slightly greater than the projected length of the pre-bent steel bars. Then, determine the longitudinal and transverse positions by using the transverse fine-adjustment screw jack 110 on the hoisting system 1. In order to determine the balance state of the steel-concrete composite segment 5 during hoisting, adjust the hoisting tool push-pull rod 206 on the hoisting tool system 2. The hoisting tool push-pull rod 206 is connected to the hoisting tool conversion seat 202. Both are located on the hoisting tool spreader beam 203, and fine-rolled threaded steel bars 207 are fixed on both sides of the hoisting tool spreader beam 203. After the hydraulic system of the hoisting tool push-pull rod 206 is subjected to force, it can push the hoisting tool conversion seat 202 to move on the hoisting tool spreader beam 203. When the hoisting tool system 2 reaches the balance state, the hoisting tool conversion seat 202 is locked by the bolts 208 on the fine-rolled threaded steel bars 207. After the adjustment is completed, the trial hoisting and formal hoisting are carried out.

[0029] S42: After hoisting to a certain distance from the design elevation, first insert the slow-setting prestressed tendons 12 of the cantilever concrete beam segment 4 into the flange of the steel-concrete composite segment 5. When continuing to hoist to the design elevation, connect the longitudinal steel bars reserved in the cantilever concrete beam segment 4 with the longitudinal steel bars pre-installed in the flange of the steel-concrete composite segment 5.

[0030] S51: The longitudinally moved steel-concrete composite section 5 is positioned by retracting the upper crossbeam push-pull rod 108 of the hanger system 1. After fine adjustment, its web, bottom plate and connecting embedded parts 3 are welded and locked. Then, the prestressed steel strands 8 of the cantilevered concrete beam section 4 are inserted into the prestressed ducts of the steel-concrete composite section 5. At the same time, the reinforcement and formwork system 9 are installed. The formwork system 9 mainly consists of wooden molds 903 and tie-rolled threaded steel bars 904 to form the main load-bearing structure. The external structure is constructed by erecting disc-lock scaffolds 901 as a construction platform. The disc-lock scaffolds 901 maintains stability through the longitudinal limiting 902 of the channel steel at the top and bottom. The disc-lock scaffolds 901 and the wooden molds 903 are connected by the channel steel attachment 905 to jointly resist part of the lateral pressure of concrete pouring. The main part of the lateral pressure is resisted by the shear nails of the steel-concrete composite section 5 connected to the steel reinforcement support 906 in the partition.

[0031] S52: Simultaneously dismantle the steel strand B112 and its corresponding lifting slings 204 of the gantry system 1, and hoist the cantilever beam system 6 onto the bridge and perform rough positioning. Install the cantilever beam anchor 603 but do not tighten it, and perform rough installation of the hanging beam 604, spiral jack 605, and hanging slings 606, but do not perform welding or tightening operations. The hanging slings 606 need to be connected to the stiffening plate 608 of the bottom plate of the steel-concrete composite section 5 before the wooden formwork 903 is closed to reduce the deformation of the bottom plate of the steel-concrete composite section 5 during the pouring of concrete 7.

[0032] S61: In order to offset the tension of the pre-embedded parts 3 connecting the upper web of the steel-concrete composite section 5 as much as possible during the pouring of concrete 7 and to control the bending moment of the poured concrete 7, some prestressed steel strands 8 are pre-tensioned before the hanging beam 604 of the cantilever beam system 6 is connected and fixed to the second lifting lug 607 on the steel-concrete composite section 5. The principle for selecting the position of the prestressed steel strands 8 is to be close to the top of the web, and the pre-tensioning force is based on offsetting the tension of the connecting pre-embedded parts 3.

[0033] S62: After tensioning, the cantilever beam system 6 is connected to the top and bottom plates of the steel-concrete composite section 5, and the front support point is pre-filled to allow the cantilever beam 601 to bear the load in advance. The cantilever beam system 6 uses the lifting lug 607 under the original steel strand B112 near the second lifting lug 607 of the lifting system 2. Its position is basically consistent with the center of gravity of the concrete 7 to be poured in the subsequent steel-concrete composite section 5. In order to reduce the deformation of the bottom plate of the steel-concrete composite section 5 during the pouring of concrete 7, a set of hanging crossbeams 604 is added near the side 4 of the cantilevered concrete beam section. Under the hanging crossbeams 604, there are hanging straps 606, which are subsequently tightened by spiral jacks 605. After the cantilever beam system 6 is connected to the top and bottom plates of the steel-concrete composite section 5, the rear anchor 603 of the cantilever beam is tightened first, then the front section of the cantilever beam 601 is pre-jacked to allow the cantilever beam 602 to bear the force in advance, and the gap between the cantilever beam embedded part 602 and the lower flange of the cantilever beam 601 is filled, and the hoisting sling 606 is tightened with a spiral jack 605.

[0034] S71: Concrete is poured in 7 layers with equal strength. The top surface of the steel beam is equipped with a placement and vibration inlet. Concrete is placed using a hopper and tremie pipe, and then poured and vibrated in layers. Some corner areas require manual vibration or venting with reinforcing bars. During the top slab pouring, due to the presence of compartments and a top slab in the steel-concrete composite section 5, the top slab of the steel-concrete composite section 5 is prone to incomplete compaction. Therefore, the pouring is carried out longitudinally from the side of the steel-concrete composite section 5 towards the side of the cantilevered concrete beam section 4, and transversely from both sides of the web, pouring from one compartment towards the centerline. Because there are openings between the compartments, it is difficult to fill the first compartment completely in one go. Therefore, during the pouring of the next adjacent compartment, attention needs to be paid to replenishing material and vibrating the previous compartment.

[0035] S72: After equal strength, prestressed steel strands 8 are tensioned and cantilever beam system 6 is removed.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A construction method for a steel-concrete hybrid rigid frame steel-concrete composite section, characterized in that, Includes the following steps: S1: Construction of the largest concrete cantilever end, during which pre-embedded steel-concrete composite section (5) pre-reserved holes and pre-embedded parts are used for construction. S2: Modify the hanging basket, install the hanging system (1), and at the same time perform pre-bending of the steel-concrete interface steel bars and inward treatment of the prestressed steel strands (8); S3: The steel-concrete composite section (5) is in place, the lifting system (2) is installed on the ship deck and the steel strands are pre-tightened; S4: After the lifting point is adjusted longitudinally and laterally by the lifting system (1), trial lifting and formal lifting are carried out. Before positioning, the slow-setting prestressed tendons (12) are inserted and the longitudinal steel bars at the flange are connected. S5: After longitudinal movement and positioning, the steel-concrete composite section (5) is locked with the connecting embedded parts (3), the prestressed steel strands (8) are threaded, and the reinforcing bars and formwork system (9) are installed; S6: Installation of prestressed steel strand (8) pretensioning and cantilever beam system (6); S7: Concrete (7) pouring of equal strength and prestressed steel strands (8) tensioning.

2. The construction method for a steel-concrete hybrid rigid frame steel-concrete composite section according to claim 1, characterized in that: In step S1, the reserved holes include the track pressure beam anchoring holes of the hanger system (1), the rear anchor pressure beam anchoring holes of the hanger system (1), and the rear anchor (603) pressure beam anchoring holes of the cantilever beam system (6). The embedded parts include the cantilever beam embedded parts (602) of the cantilever beam system (6) and the connection embedded parts (3) on the end section of the cantilever concrete beam segment (4).

3. The construction method for a steel-concrete hybrid rigid frame steel-concrete composite section according to claim 1, characterized in that: In step S2, the modified hanging basket is to move the hanging basket forward and lower the side formwork and hanging basket hoisting system to the barge below after the last cantilevered concrete beam segment (4) is completed; the installation of the hanging frame system (1) is specifically to install a transverse support (106) on the upper crossbeam of the modified hanging basket, and install a hydraulic continuous jack (105) and a longitudinal and transverse sliding device on it; then the lower construction platform (11) is installed, and the pre-numbered hoisting steel strand A (111) and steel strand B (112) are respectively threaded into the hydraulic continuous jack A (104) and hydraulic continuous jack B (105).

4. The construction method for a steel-concrete hybrid rigid frame steel-concrete composite section according to claim 1, characterized in that: In step S2, before hoisting the steel-concrete composite section (5), the beam end section needs to be accurately measured and laid out. Based on the layout results, the composite surface is roughened and the steel-concrete interface steel bars are pre-bent into the box at a certain angle. Then, the prestressed steel strands (8) are bundled and then moved into the box chamber.

5. The construction method for a steel-concrete hybrid rigid frame steel-concrete composite section according to claim 1, characterized in that: In step S3, the steel-concrete composite section (5) is transported to the bridge site by ship. On the ship deck, the lifting system (2) is first connected to the first lifting lug (205) on the top plate of the steel-concrete composite section (5). Then, the steel strands A (111) and B (112) suspended from the lifting system (1) are threaded into the lifting connection seat (201), and each lifting steel strand is pre-tightened on the lowering construction platform (11).

6. The construction method for a steel-concrete hybrid rigid frame steel-concrete composite section according to claim 1, characterized in that: In step S4, the longitudinal and transverse positions are first determined by the upper crossbeam push-pull rod (108) and the transverse fine-tuning screw jack (109) on the lifting system (1). Then, in order to determine the balance state of the steel-concrete composite section (5) during hoisting, the lifting tool push-pull rod (206) on the lifting tool system (2) is adjusted. After the adjustment is completed, the trial hoisting and formal hoisting are carried out. After hoisting to a certain distance from the design elevation, the slow-setting prestressed tendons (12) of the cantilever concrete beam section (4) are first inserted into the flange of the steel-concrete composite section (5). When hoisting to the design elevation, the longitudinal steel bars reserved in the cantilever concrete beam section (4) are connected to the longitudinal steel bars pre-installed in the flange of the steel-concrete composite section (5).

7. The construction method for a steel-concrete hybrid rigid frame steel-concrete composite section according to claim 5, characterized in that: In step S5, the longitudinally moved steel-concrete composite section (5) is positioned by the upper crossbeam push rod (108) of the hanger system (1). After fine adjustment, its web plate is welded and locked to the connecting embedded part (3). Then, the prestressed steel strands (8) of the cantilevered concrete beam section (4) are inserted into the prestressed duct of the steel-concrete composite section (5), and the reinforcement and formwork system (9) are installed simultaneously. The cantilever beam system (6) is hoisted onto the bridge and roughly positioned simultaneously.

8. The construction method for a steel-concrete hybrid rigid frame steel-concrete composite section according to claim 6, characterized in that: In step S6, in order to counteract the tension of the pre-embedded parts (3) at the top of the steel-concrete composite section and control the bending moment as much as possible, some prestressed steel strands (8) are pre-tensioned before the cantilever beam system (6) is fixed. After tensioning, the cantilever beam system (6) is connected to the top and bottom plates of the steel-concrete composite section (5), and the front support is padded to make the cantilever beam bear the force in advance.

9. A construction method for a steel-concrete hybrid rigid frame steel-concrete composite section according to claim 7, characterized in that: In step S7, concrete (7) is poured in layers of equal strength, prestressed steel strands (8) are tensioned, and the cantilever beam system (6) is dismantled.

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