Precast steel cage structure for bridge piers and its construction method

Abstract

This invention discloses a precast steel reinforcement cage structure for bridge piers and its construction method, belonging to the field of building construction technology. In this invention, by prefabricating the steel reinforcement cage for bridge piers, the precise positioning and physical quality of the pier reinforcement are effectively guaranteed. The steel reinforcement cage is centrally cut and processed, a step that can be completed in advance at the steel reinforcement yard. It can be hoisted after the foundation formwork is installed, directly saving on-site binding time and effectively shortening the on-site binding efficiency. Compared to on-site construction, processing at the steel reinforcement yard and using a gantry crane for steel reinforcement transportation saves on crane rental costs. Furthermore, working at a higher elevation in the steel reinforcement yard is simpler than on-site work, reducing the number of workers and labor costs, improving construction efficiency, reducing construction noise, and enhancing environmental safety.

Description

Technical Field

[0001] This invention belongs to the field of building construction technology, and in particular relates to a precast steel cage structure for bridge piers and its construction method. Background Technology

[0002] With the rapid development of urban expressways, the scale of urban elevated road construction is getting larger and larger. Due to the dense steel bars and large diameter of the steel bars in the piers of urban elevated roads, it is difficult to tie the steel bars on site. It is also difficult to control the spacing of the steel bars and the external dimensions of the steel bar skeleton. The on-site welding conditions are poor, the welding quality is difficult to guarantee, the tying period is long, and the workload of high-altitude operations is large, resulting in high safety risks.

[0003] To address the aforementioned issues, improve the quality and efficiency of pier reinforcement installation, and reduce construction costs, the project developed an integral prefabrication and installation technology for pier reinforcement. This new technology allows for better quality control of reinforcement spacing and overall cage dimensions, effectively improving the pass rate of the pier reinforcement protective layer. In terms of schedule, since the pier reinforcement cutting and binding are completed at the rebar yard, the entire rebar cage can be hoisted before the foundation is poured, directly saving on-site binding time and significantly shortening the construction period. Regarding safety, processing the pier reinforcement at the rebar yard avoids the dangers of workers operating at heights compared to traditional on-site binding, enhancing construction safety. However, some common problems exist in the integral prefabrication and installation of pier reinforcement that need to be addressed:

[0004] 1. During the steel reinforcement fabrication process, the irregular cross-section of the steel reinforcement cage makes it difficult to tie and shape the steel reinforcement as a whole, which can easily lead to dimensional deviations.

[0005] 2. During the hoisting of the pier reinforcement cage, due to the large overall weight of the reinforcement cage, if the reinforcement cage is not reinforced, the main reinforcement and stirrups are prone to displacement and deformation.

[0006] 3. High precision is required for the on-site installation, positioning, and verticality control of the reinforcing cage;

[0007] Therefore, there are certain problems and room for improvement in the safe installation of pier reinforcement bars, and a mature technology for the overall prefabrication and installation of pier reinforcement bars is needed. Summary of the Invention

[0008] The purpose of this invention is to address the problems of high construction difficulty of pier reinforcement and common quality defects in pier reinforcement processing and installation, and to propose a precast steel cage structure for bridge piers and its construction method.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A construction method for a precast steel cage structure for bridge piers includes the following steps:

[0011] S101. Fabrication of pier reinforcement cage: Design the spacing of the main reinforcement bars of the pier body and the outer dimensions of the reinforcement cage according to the construction requirements, and pre-set the positioning mold. The reinforcement cage is prefabricated and welded using the positioning mold.

[0012] S102. The steel cage for the pier body is hoisted. The hoisting tonnage is calculated based on the weight of the steel cage. After being transported to the site, the entire cage is safely lifted and placed in position.

[0013] S103. Positioning and installation of the pier reinforcement cage: After marking the landing point of the pier reinforcement cage, the pier reinforcement cage is positioned and installed using positioning hoops. The pier reinforcement cage is then supported by welded steel bars on the foundation pad, thus completing the installation.

[0014] As a further description of the above technical solution:

[0015] The specific method for fabricating the pier reinforcement cage in S101 includes:

[0016] S201. Install the main reinforcement bars of the pier body on the jig. The jig positioning unit spacing is 2m. The frame is made of channel steel. The positioning clamps are made of steel plates with slots cut according to the design spacing of the main reinforcement bars of the pier body.

[0017] S202. Install the steel reinforcement cage shaping sleeve, and the cross-sectional shape of the positioning sleeve is designed according to the cross-sectional shape of the pier body steel reinforcement. First, install the side pier body steel reinforcement cage to make positioning fixtures, and then install the upper positioning fixtures. The positioning fixtures must be installed in close contact with the shaping sleeves to prevent the subsequent main reinforcement positions from deviating. After the positioning fixtures are installed, the main reinforcements are positioned through the slots of the positioning fixtures.

[0018] S203. Remove the positioning fixture for the pier reinforcement cage, install stirrups and weld reinforcing bars to strengthen the reinforcement skeleton. After the main reinforcement bars are positioned by the positioning fixture and welded to the shaped stirrups, weld reinforcing bars on the inside of the main reinforcement bars on the side to strengthen the skeleton, and then remove the positioning fixture.

[0019] As a further description of the above technical solution:

[0020] During the welding process, the remaining stirrups in the steel cage must be aligned front to back, and the front and back positions of different stirrups on the same cross section must be consistent.

[0021] As a further description of the above technical solution:

[0022] The specific steps for hoisting the pier reinforcement cage in S102 include:

[0023] S301, The steel cage was loaded onto the truck and transported to the site;

[0024] S302. Welding lifting point reinforcement bars: Welding cross-shaped reinforcement bars to the main reinforcement bars at the top of the pier as support; Before lifting the pier body reinforcement bars as a whole, welding reinforcement bars to the top and middle of the reinforcement cage as lifting points.

[0025] S303, bolted wire ropes, and the wire ropes used by truck cranes are of equal length;

[0026] S304, after the steel cage is lifted as a whole;

[0027] S305. Rotate the steel cage to a vertical position;

[0028] S306. Hoist to the design position, stop lifting and lower the steel cage into place.

[0029] As a further description of the above technical solution:

[0030] The positioning steps for the pier reinforcement cage in S103 include:

[0031] S401. Total station point layout: Use a total station for precise layout and mark the corner points of the pier reinforcement on the surface layer of the foundation.

[0032] S402. Weld the positioning bars of the steel cage according to the corner points of the pier body steel reinforcement laid out.

[0033] S403. Positioning of the rebar cage: hoist the rebar cage and lower it from the inside of the positioning bar to the design elevation, and fine-tune the plane position and verticality of the rebar cage.

[0034] S404. Welded steel cage support reinforcement: The same type of support reinforcement as the main reinforcement is used and welded to the main reinforcement so that the steel cage is supported on the foundation concrete.

[0035] S405. Install guy ropes. Pull four guy ropes at the top and middle of the steel cage and secure them with metal clips.

[0036] As a further description of the above technical solution:

[0037] The guy rope has a diameter of not less than 12mm, and the other end of the guy rope is fixed to the ground anchor by a tensioner.

[0038] As a further description of the above technical solution:

[0039] The invention includes a precast steel cage structure for a bridge pier, which is applied to a construction method for a precast steel cage structure for a bridge pier. The precast steel cage structure includes multiple positioning sleeves, which are axially opposite to each other, and a support block is fixedly connected between the positioning sleeves. Multiple limiting grooves are equidistantly opened on one side of the support block, and a steel bar body is inserted through the axially opposite limiting grooves. An adjustment mechanism is provided at the corresponding position of the limiting groove on one side of the support block.

[0040] As a further description of the above technical solution:

[0041] The adjustment mechanism includes an adjustment plate, with fixed blocks fixedly connected to both ends of both sides of the adjustment plate. The fixed blocks are fixedly connected to one side of the inner cavity of the positioning sleeve. A threaded cylinder is rotatably connected to one side of the fixed block via a bearing. An adjustment screw is threadedly connected to the threaded cylinder. An adjustment block is fixedly connected to the end of the adjustment screw. A receiving ring is fixedly connected to the end of the adjustment block. The receiving ring is sleeved on one side of the limiting groove.

[0042] As a further description of the above technical solution:

[0043] An adjusting block is fixedly connected to the outer wall of the threaded cylinder.

[0044] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0045] 1. In this invention, by prefabricating the steel reinforcement cages for bridge piers, the precise positioning and physical quality of the pier reinforcement are effectively guaranteed. The steel reinforcement cages are centrally cut and processed, which can be completed in advance at the steel reinforcement yard. After the foundation formwork is installed, the cages can be hoisted, directly saving the time spent on on-site binding and effectively shortening the on-site binding time. Compared with on-site construction, processing the steel reinforcement at the steel reinforcement yard and transporting the steel reinforcement by gantry crane can save on crane rental costs. Moreover, working at a higher altitude in the steel reinforcement yard is simpler than on-site, which can reduce the number of construction workers and reduce labor costs accordingly, improve construction efficiency, reduce construction noise, and improve environmental safety.

[0046] 2. In this invention, when prefabricating the reinforcing bars of bridge piers, positioning sleeves can be placed on one side of the positioning fixture, allowing the reinforcing bars to be inserted into the corresponding receiving rings and limiting grooves. By moving the reinforcing bars between multiple arranged positioning sleeves, the reinforcing bars can be calibrated and positioned. After the support blocks support the pier from the periphery, the pier can be quickly welded, facilitating the subsequent addition of support bars and shaping sleeves. This facilitates rapid prefabrication of bridge piers. Furthermore, after the reinforcing bars are placed in the positioning sleeves, the threaded cylinder can be rotated within the adjusting plate by turning the adjusting block. The rotation of the threaded cylinder can move the inner adjusting screw, which can then pull the reinforcing bar fitted inside the receiving ring on the other side for fine-tuning. This allows for the adjustment of the angle of the fine-tuned reinforcing bars through the movement of the receiving ring, improving the calibration and positioning accuracy of the reinforcing bars and enhancing the safety and stability of the hoisting process. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the assembly structure of a precast steel cage structure for a bridge pier proposed in this invention.

[0048] Figure 2 This is a side view of the positioning hoop structure of a precast steel cage structure for bridge piers proposed in this invention.

[0049] Figure 3 The present invention proposes Figure 2 Enlarged structural diagram of part A in the middle;

[0050] Figure 4 This is a schematic diagram of the transverse structure of a precast steel cage structure for a bridge pier proposed in this invention.

[0051] Figure 5 This is a schematic diagram of the lateral structure of a precast steel cage structure for a bridge pier proposed in this invention.

[0052] Figure 6 This is a schematic diagram showing the disassembly and assembly of a precast steel cage structure for a bridge pier proposed in this invention.

[0053] Figure 7 This is a schematic diagram of the hoisting process of a precast steel cage structure for a bridge pier, as proposed in this invention.

[0054] Figure 8 This is a schematic diagram of the lateral splitting structure of a precast steel cage structure for bridge piers proposed in this invention.

[0055] Figure 9 This is a top-view structural diagram of a precast steel cage structure for a bridge pier proposed in this invention.

[0056] Figure 10 This is a front view schematic diagram of a precast steel cage structure for bridge piers proposed in this invention.

[0057] Legend:

[0058] 1. Reinforcing bar body; 2. Positioning hoop; 3. Support block; 4. Limiting groove; 5. Adjustment mechanism; 501. Adjusting plate; 502. Threaded cylinder; 503. Adjusting block; 504. Adjusting screw; 505. Receiving ring. Detailed Implementation

[0059] 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.

[0060] Please see Figure 1-10 This invention provides a technical solution: a construction method for a precast steel cage structure for bridge piers, specifically including the following steps:

[0061] S101. Fabrication of pier reinforcement cage: Design the spacing of the main reinforcement bars of the pier body and the outer dimensions of the reinforcement cage according to the construction requirements, and pre-set the positioning mold. The reinforcement cage is prefabricated and welded using the positioning mold.

[0062] S102. The steel cage for the pier body is hoisted. The hoisting tonnage is calculated based on the weight of the steel cage. After being transported to the site, the entire cage is safely lifted and placed in position.

[0063] S103. Positioning and installation of the pier reinforcement cage: After marking the landing point of the pier reinforcement cage, the pier reinforcement cage is positioned and installed using positioning hoops. The pier reinforcement cage is then supported by welded steel bars on the foundation pad, thus completing the installation.

[0064] The specific method for fabricating the pier reinforcement cage in S101 includes:

[0065] S201. Install the main reinforcement bars of the pier body on the jig. The jig positioning unit spacing is 2m. The frame is made of channel steel. The positioning clamps are made of steel plates with slots cut according to the design spacing of the main reinforcement bars of the pier body.

[0066] S202. Install the steel reinforcement cage shaping sleeve, and the cross-sectional shape of the positioning sleeve is designed according to the cross-sectional shape of the pier body steel reinforcement. First, install the side pier body steel reinforcement cage to make positioning fixtures, and then install the upper positioning fixtures. The positioning fixtures must be installed in close contact with the shaping sleeves to prevent the subsequent main reinforcement positions from deviating. After the positioning fixtures are installed, the main reinforcements are positioned through the slots of the positioning fixtures.

[0067] S203. Remove the pier reinforcement cage, make positioning fixtures, install stirrups and weld reinforcing bars to strengthen the reinforcement skeleton. After the main bars are positioned by the positioning fixtures and welded to the shaped stirrups, weld reinforcing bars on the inside of the main bars on the side to strengthen the skeleton, and then remove the positioning fixtures.

[0068] During the welding process, the remaining stirrups in the steel cage must be aligned front to back, and the front and back positions of different stirrups in the same cross section must be consistent.

[0069] The specific steps for hoisting the pier reinforcement cage in S102 include:

[0070] S301, The steel cage was loaded onto the truck and transported to the site;

[0071] S302. Welding lifting point reinforcement bars: Welding cross-shaped reinforcement bars to the main reinforcement bars at the top of the pier as support; Before lifting the pier body reinforcement bars as a whole, welding reinforcement bars to the top and middle of the reinforcement cage as lifting points.

[0072] S303, bolted wire ropes, and the wire ropes used by truck cranes are of equal length;

[0073] S304, after the steel cage is lifted as a whole;

[0074] S305. Rotate the steel cage to a vertical position;

[0075] S306. Hoist to the design position, stop lifting and lower the steel cage into place.

[0076] Among them, the main reinforcement bars at the top of the pier are welded with cross-shaped ф32 reinforcing bars as support;

[0077] Before lifting the pier reinforcement as a whole, weld ф32 and ф16 reinforcing bars to the top and middle of the reinforcement cage respectively as lifting points. The welding of the reinforcing bars must be firm to prevent the reinforcement bars from deforming or the lifting from failing due to the weight of the reinforcement cage, thus ensuring construction safety.

[0078] The steel wire ropes used by the truck crane must be of equal length to ensure that the steel cage is in a vertical position after the initial lifting is completed, so as to facilitate the accurate positioning of the subsequent landing point of the steel cage.

[0079] The type of truck crane used for hoisting is determined based on the height of the reinforcing cage, specifically including:

[0080] When the height of the reinforcing cage is less than 8m:

[0081] At this time, the steel cage is relatively short and light, so a 50T truck crane can be used for the lifting operation.

[0082] During hoisting, the truck crane's wire ropes are fixed to the top and middle lifting points of the steel cage, and the hook is slowly raised. After the steel cage is completely off the ground, the main hook is raised and the auxiliary hook is lowered until the steel cage is in a vertical position. After that, the lifting is stopped and the steel cage is lowered into place.

[0083] When 8m ≤ steel cage height < 14m:

[0084] At this point, the steel cage is tall and heavy, so the hoisting operation requires the use of two truck cranes, one large and one small (80T and 50T), working together to complete the task.

[0085] During hoisting, four wire ropes of the 80T truck crane are fixed to the lifting point on the top of the pier, and four wire ropes of the 50T truck crane are fixed to the lifting point in the middle of the rebar cage. The 50T truck crane only plays an auxiliary role, and its lifting speed must not exceed that of the 80T truck crane. It is mainly used for initial lifting to get the entire rebar cage off the ground and avoid deformation caused by the rebar hitting the ground. After the entire rebar cage is off the ground, the 80T truck crane continues to raise its main hook, while the 50T truck crane lowers its main hook. Once the rebar cage is lifted to a vertical position, the 80T truck crane completes the remaining hoisting work alone.

[0086] The positioning steps for the pier reinforcement cage in S103 include:

[0087] S401. Total station point layout: Use a total station for precise layout and mark the corner points of the pier reinforcement on the surface layer of the foundation.

[0088] S402. Weld the positioning bars of the steel cage according to the corner points of the pier body steel reinforcement laid out.

[0089] S403. Positioning of the rebar cage: hoist the rebar cage and lower it from the inside of the positioning bar to the design elevation, and fine-tune the plane position and verticality of the rebar cage.

[0090] S404. Welded steel cage support reinforcement: The same type of support reinforcement as the main reinforcement is used and welded to the main reinforcement to support the steel cage on the foundation concrete. Each side of the steel cage is welded with 4 support reinforcements, for a total of 16 support reinforcements.

[0091] S405. Install guy ropes. Pull four guy ropes at the top and middle of the steel cage and secure them with metal clips.

[0092] The guy rope has a diameter of not less than 12mm, and the other end of the guy rope is fixed to the ground anchor by a tensioner.

[0093] The materials used are standard materials for bridge structure construction, mainly including: C12mm steel bars, ф32mm steel bars, positioning molds, ф12mm guy ropes, ground anchors, rope tensioners, metal clips, etc. The equipment includes standard equipment such as steel bar bending machines and truck cranes.

[0094] Furthermore, the technical requirements of the construction design drawings and relevant specifications shall be implemented.

[0095] The positioning fixtures for the pier reinforcement cage are precisely fabricated in the factory and installed and disassembled precisely according to the prescribed steps.

[0096] Standardized construction procedures: Prepare for construction, scientifically arrange construction procedures, and organize construction according to process requirements, ensuring that self-inspection is carried out during construction.

[0097] Standardized construction operations: Technical instructions are used as the basis for construction, and qualified operators are selected according to their professional trades.

[0098] Standardized construction management: Construction is guided by the "process operation procedure"; construction is managed in accordance with the project quality objectives and other quality management systems; construction operation instructions, briefings, and technical notices are written in a rigorous, clear, and accurate manner.

[0099] The steel reinforcement cage of the pier body is reinforced with welded reinforcing bars and the lifting points are strengthened to prevent the steel reinforcement cage from deforming or falling apart during the lifting process.

[0100] After hoisting, the guy ropes of the steel reinforcement cage on the pier are connected to the ground anchors for fixation to prevent the steel reinforcement cage from overturning due to strong winds or other severe weather.

[0101] Establish and improve the safety production management organization, set up a safety production leading group headed by the project manager to be fully responsible for and lead the safety production work of the project; and implement a hierarchical safety technical briefing and training system to ensure that management personnel and on-site construction personnel master the technical points and understand the safety risks, so as to prevent problems before they occur.

[0102] When hoisting and processing the steel reinforcement cage for the pier body, the "Ten Don'ts" principle and the "Ten Don'ts" regulations must be strictly followed, and no violations shall be carried out.

[0103] Safety protection facilities must be set up at the construction site in accordance with regulations to ensure the safety of personnel and facilities in the construction site and adjacent areas.

[0104] Before operation, the lifting equipment and lifting tools must be inspected and confirmed to be safe before use.

[0105] A warning zone must be set up during the hoisting of the steel cage, and unauthorized personnel are strictly prohibited from entering the work area.

[0106] This technology effectively ensures the precise positioning and structural quality of the pier reinforcement. The pier reinforcement cages are centrally prepared and processed, a step that can be completed in advance at the reinforcement yard. They can then be hoisted after the foundation formwork is installed, directly eliminating on-site tying time and shortening the construction period for each pier by an average of 3 days. Compared to on-site construction, processing the reinforcement at the yard and using a gantry crane for transporting the reinforcement saves on crane rental costs. Furthermore, working at a higher elevation in the reinforcement yard simplifies operations compared to on-site work, reducing the number of workers and consequently lowering labor costs.

[0107] Compared to traditional on-site reinforcement binding technology for piers, this technology processes the pier reinforcement cages within a fully enclosed reinforcement yard, significantly reducing construction noise. Overhead cranes replace truck cranes for transporting semi-finished reinforcement, and energy consumption is converted from oil to electricity, making it more environmentally friendly and reducing pollution. Tooling and other materials are readily available on construction sites, requiring no additional resource investment.

[0108] This technology effectively ensures that the position, spacing, and protective layer of the pier reinforcement meet design requirements by replacing manual control with tooling and replacing old processes with new ones. It improves the overall installation quality and construction efficiency of the pier reinforcement, reduces construction costs, and has significant effects. Compared with existing technologies, this technology has certain advantages in terms of practicality and scalability, and has broad prospects for promotion and application.

[0109] A precast steel cage structure for bridge piers includes multiple positioning sleeves 2, which are axially opposite to each other, and a support block 3 is fixedly connected between the positioning sleeves 2. Multiple limiting grooves 4 are equidistantly opened on one side of the support block 3, and a steel body 1 is inserted through the axially opposite limiting grooves 4. An adjustment mechanism 5 is provided at the corresponding position of the limiting groove 4 on one side of the support block 3.

[0110] The adjustment mechanism 5 includes an adjustment plate 501. Both ends of the adjustment plate 501 are fixedly connected to fixed blocks, and the fixed blocks are fixedly connected to one side of the inner cavity of the positioning sleeve 2. A threaded cylinder 502 is rotatably connected to one side of the fixed block via a bearing. An adjustment screw 504 is threadedly connected to the inner thread of the threaded cylinder 502. An adjustment block 503 is fixedly connected to the end of the adjustment screw 504. A receiving ring 505 is fixedly connected to the end of the adjustment block 503. The receiving ring 505 is sleeved on one side of the limiting groove 4. An adjustment block 503 is fixedly connected to the outer wall of the threaded cylinder 502. The adjustment block 503 has a hexagonal cross-sectional shape and can be rotated by an open-end wrench or a socket.

[0111] Working principle: When in use, after the positioning sleeve 2 is set on one side of the positioning fixture, the steel bar can be inserted into the corresponding receiving ring 505 and the limiting groove 4. After the steel bar is inserted between multiple arranged positioning sleeves 2, the steel bar can be calibrated and positioned. After the support block 3 supports the pier body from the periphery, the pier body can be quickly welded. This facilitates the subsequent addition of support bars and shaping sleeves, which is conducive to the rapid processing of bridge pier prefabrication. After the steel bar is inserted into the positioning sleeve 2, the threaded cylinder 502 can be rotated in the adjusting plate 501 by turning the adjusting block 503. The rotation of the threaded cylinder 502 can drive the inner adjusting screw 504 to move. The movement of the adjusting screw 504 can pull the steel bar sleeved in the receiving ring 505 on the other side for fine adjustment.

[0112] 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 construction method for a precast reinforced steel cage structure for bridge piers, characterized in that, Specifically, the following steps are included: S101. Fabrication of pier reinforcement cage: Design the spacing of the main reinforcement bars of the pier body and the outer dimensions of the reinforcement cage according to the construction requirements, and pre-set the positioning mold. The reinforcement cage is prefabricated and welded using the positioning mold. S102. The steel reinforcement cage of the pier body is hoisted. The hoisting tonnage is calculated based on the weight of the steel reinforcement cage. After being transported to the site, the entire cage is safely lifted and placed in position. S103. Positioning and installation of the pier reinforcement cage: After marking the landing point of the pier reinforcement cage, the pier reinforcement cage is placed and installed using positioning hoops. The pier reinforcement cage is supported by welding steel bars on the foundation pad, and the installation is completed. The positioning steps for the pier reinforcement cage in S103 include: S401. Total station point layout: Use a total station for precise layout and mark the corner points of the pier reinforcement on the surface layer of the foundation. S402. Weld the positioning bars of the steel cage according to the corner points of the pier body steel reinforcement laid out. S403. Positioning of the rebar cage: hoist the rebar cage and lower it from the inside of the positioning bar to the design elevation, and fine-tune the plane position and verticality of the rebar cage. S404. Welded steel cage support reinforcement: The same type of support reinforcement as the main reinforcement is used and welded to the main reinforcement so that the steel cage is supported on the foundation concrete. S405. Install guy ropes. Pull four guy ropes at the top and middle of the steel cage and secure them with metal clips. It also includes a precast steel cage structure for a bridge pier, which is applied to a construction method of a precast steel cage structure for a bridge pier. The precast steel cage structure includes multiple positioning sleeves (2), and the multiple positioning sleeves (2) are axially opposite to each other. A support block (3) is fixedly connected between the positioning sleeves (2). Multiple limiting grooves (4) are equidistantly opened on one side of the support block (3), and a steel body (1) is inserted through the axially opposite limiting grooves (4). An adjustment mechanism (5) is provided at the corresponding position of the limiting groove (4) on one side of the support block (3). The adjustment mechanism (5) includes an adjustment plate (501). Both ends of the adjustment plate (501) are fixedly connected to a fixing block, and the fixing block is fixedly connected to one side of the inner cavity of the positioning sleeve (2). A threaded cylinder (502) is rotatably connected to one side of the fixing block through a bearing. An adjustment screw (504) is threadedly connected to the threaded cylinder (502). An adjustment block (503) is fixedly connected to the end of the adjustment screw (504). A receiving ring (505) is fixedly connected to the end of the adjustment block (503). The receiving ring (505) is sleeved on one side of the limiting groove (4).

2. The construction method for a precast steel cage structure for bridge piers according to claim 1, characterized in that, The specific method for fabricating the pier reinforcement cage in S101 includes: S201. Install the main reinforcement bars of the pier body on the jig. The jig positioning unit spacing is 2m. The frame is made of channel steel. The positioning clamps are made of steel plates with slots cut according to the design spacing of the main reinforcement bars of the pier body. S202. Install the steel reinforcement cage shaping sleeve, and the cross-sectional shape of the positioning sleeve is designed according to the cross-sectional shape of the pier body steel reinforcement. First, install the side pier body steel reinforcement cage to make positioning fixtures, and then install the upper positioning fixtures. The positioning fixtures must be installed in close contact with the shaping sleeves to prevent the subsequent main reinforcement positions from deviating. After the positioning fixtures are installed, the main reinforcements are positioned through the slots of the positioning fixtures. S203. Remove the positioning fixture for the pier reinforcement cage, install stirrups and weld reinforcing bars to strengthen the reinforcement skeleton. After the main reinforcement bars are positioned by the positioning fixture and welded to the shaped stirrups, weld reinforcing bars on the inside of the main reinforcement bars on the side to strengthen the skeleton, and then remove the positioning fixture.

3. The construction method for a precast steel cage structure for bridge piers according to claim 2, characterized in that, During the welding process, the remaining stirrups in the steel cage must be aligned front to back, and the front and back positions of different stirrups in the same cross section must be consistent.

4. The construction method for a precast steel cage structure for bridge piers according to claim 1, characterized in that, The specific steps for hoisting the pier reinforcement cage in S102 include: S301, The steel cage was loaded onto the truck and transported to the site; S302. Welding lifting point reinforcement bars: Welding cross-shaped reinforcement bars to the main reinforcement bars at the top of the pier as support; Before lifting the pier body reinforcement bars as a whole, welding reinforcement bars to the top and middle of the reinforcement cage as lifting points. S303, bolted wire ropes, and the wire ropes used by truck cranes are of equal length; S304, after the steel cage is lifted as a whole; S305. Rotate the steel cage to a vertical position; S306. Hoist to the design position, stop lifting and lower the steel cage into place.

5. The construction method for a precast steel cage structure for bridge piers according to claim 4, characterized in that, The guy rope has a diameter of not less than 12mm, and the other end of the guy rope is fixed to the ground anchor by a tensioner.

6. The construction method for a precast steel cage structure for bridge piers according to claim 4, characterized in that, An adjusting block (503) is fixedly connected to the outer wall of the threaded cylinder (502).

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