A method for prefabricating segmental steel box girders for cable-stayed bridges

Abstract

This application discloses a method for the segmental prefabrication of steel box girders for cable-stayed bridges. The method involves dividing a standard segment laterally into three welded modules for fabrication, creating temporary matching components, and erecting a jig in a pre-assembly yard. The three welded modules are then sequentially hoisted and aligned laterally on the jig to complete the placement of a set of standard segments to be assembled. This placement process is repeated, and the three welded modules are then matched into standard segments using the temporary matching components. Multiple standard segments are then matched into a steel box girder assembly. The temporary matching components are then disconnected, leaving one set of standard segments at the rear of the jig. A girder transport vehicle is used to transfer the remaining welded modules one by one to the next construction area, while the rear set of standard segments is moved to the front of the jig. Finally, steps S2 and S3 are repeated to complete the segmental prefabrication of the steel box girder. This application achieves the purpose of transporting steel box girders in narrow access roads.

Description

Technical Field

[0001] This application relates to the technical field of prefabrication construction of steel box girders, and in particular to a method for segmental prefabrication construction of segmental steel box girders for cable-stayed bridges. Background Technology

[0002] The main girder construction of cable-stayed bridges often adopts the cantilever assembly method using bridge deck cranes. Before the bridge deck assembly, the standard segments of each steel box girder are pre-assembled in the pre-assembly yard. After the matching requirements between adjacent standard segments are met, the standard segments are transported one by one to the gantry crane lifting station on the bridge deck in the assembled order, and then the subsequent beam feeding construction is carried out.

[0003] When constructing a long-span bridge at the dock, there is a problem with the access road being narrow. However, the standard segment length of the steel box girder is 30m and the width is 16m, which is not conducive to the transport vehicle moving the steel box girder on the narrow access road. Therefore, there is still room for improvement. Summary of the Invention

[0004] To facilitate the transfer of steel box girders in narrow passageways, this application provides a method for the segmental prefabrication of steel box girders for cable-stayed bridges.

[0005] This application provides a method for segmental prefabrication of segmental steel box girders for cable-stayed bridges, which adopts the following technical solution:

[0006] A method for prefabricating segmental steel box girders for cable-stayed bridges includes the following steps:

[0007] S1: Construction preparation: Divide the standard segment into three welding modules laterally for fabrication, make temporary matching parts, and set up a jig in the pre-assembly yard.

[0008] S2: Steel box girder pre-assembly: Three welded modules are hoisted and placed horizontally on the jig and aligned to complete the positioning step of a set of standard segments to be assembled; the positioning step of standard segments to be assembled is repeated, and then temporary matching parts are used to match the three welded modules into standard segments, and multiple standard segments are matched into a steel box girder composite segment.

[0009] S3: Transfer of welding modules: Disconnect the temporary matching parts, leaving a set of standard segments at the last end of the jig. Use the beam transport vehicle to transfer the remaining welding modules one by one to the next construction area, and move the set of standard segments at the last end of the jig to the front end of the jig.

[0010] S4: Repeat S2 and S3 to complete the segmented prefabrication of the steel box girder.

[0011] By adopting the above technical solution, the standard segment is divided into three welded modules for transportation, which facilitates loading and unloading by the beam transport vehicle and makes it easier to transfer the steel box girder in narrow access roads. In addition, a jig is built in the pre-assembly area, and temporary matching parts are used to assemble adjacent welded modules to form a complete standard segment and complete the assembly of adjacent standard segments, which improves the subsequent installation accuracy on the bridge deck. After the other groups of standard segments are disassembled, the last group is left in the jig as a template to continue the subsequent standard stages, which can achieve continuous assembly accuracy.

[0012] Preferably, in step S1, mounting seats are installed on both sides of the tire frame, and slide rails are slidably connected to the upper ends of the two mounting seats. The slide rails are used for temporary matching parts to connect. The two slide rails are respectively inclined downwards towards the three division points of the standard segment.

[0013] By adopting the above technical solution, the temporary matching parts can slide down to the three-eighths division point of the standard segment under their own gravity and be in place, which helps to improve the installation efficiency of the temporary matching parts.

[0014] Preferably, the slide rail includes an inclined storage section and a horizontal buffer section. The horizontal buffer section is located at the inclined lower end of the inclined storage section and is provided with a discharge port, which is located directly above the trisection point of the standard segment.

[0015] By adopting the above technical solution, the inclined storage section not only serves as a guide but also has a storage function. A discharge port is set in the horizontal buffer section to allow for continuous material discharge. Workers do not need to carry temporary matching parts, and the positioning operation of temporary matching parts is simplified, which helps to reduce the workload of workers.

[0016] Preferably, the temporary matching component includes two L-shaped plates, each corresponding to one of the two adjacent welding modules. The two L-shaped plates are attached to each other and fixed with bolts. In step S2, the temporary matching component is lowered to the joint of the adjacent welding modules via a slide rail, and then the two L-shaped plates of the temporary matching component are fixed to the upper surface of the corresponding welding modules. In the unlocking step of the temporary matching component in step S3, the bolts between the two L-shaped plates are removed to disconnect the adjacent welding modules.

[0017] By adopting the above technical solution, the assembly and disassembly functions of adjacent welding modules can be realized, which helps to improve the assembly and disassembly efficiency of welding modules.

[0018] Preferably, the L-shaped plate includes vertical plates and horizontal plates that are perpendicular to each other. In the same temporary matching component, two of the vertical plates abut against each other, and two of the horizontal plates are assembled to form a square base plate that fits the width of the slide rail. In step S1, the temporary matching component is stored in the inclined storage section of the slide rail. The temporary matching component used between adjacent welding modules has the same structure as the temporary matching component used between adjacent standard sections. In the inclined storage section, every two temporary matching components used between adjacent welding modules are provided with one temporary matching component used between adjacent standard sections. In step S2, the slide rail moves longitudinally and releases the temporary matching components one by one.

[0019] By adopting the above technical solution, the positions of temporary matching parts between adjacent welding modules and temporary matching parts for adjacent standard sections are adjusted. Thus, the temporary matching parts between adjacent welding modules and between adjacent standard sections can be positioned simultaneously during the longitudinal sliding of the slide rail, which helps to improve the overall installation efficiency of the temporary matching parts.

[0020] Preferably, a cylinder is provided at the inclined lower end of the slide rail, and an electromagnet is provided at the end of the cylinder. The L-shaped plate is made of iron. In step S2, during the process of the slide rail moving to the designated position, the electromagnet is energized and magnetically fixes the L-shaped plate. When the slide rail is in place at the designated position, the cylinder retracts and uses the electromagnet to attract the temporary matching part to the material discharge port. When the material is discharged, the electromagnet is de-energized and releases the temporary matching part, which falls vertically to the corresponding installation position.

[0021] To prevent the temporary matching part from sliding down to the material drop port and falling directly, which could easily cause it to collide and bounce out of its installation position, the above-mentioned technical solution uses cylinders and electromagnets to restrict and pull, which helps to achieve the goal of stable vertical falling of the temporary matching part, so that the temporary matching part can be stably positioned.

[0022] Preferably, the bottom of the slide rail is provided with a through groove, which extends along the length of the slide rail and communicates with the material discharge port. In step S1, an adhesive is applied to the bottom of the horizontal plate, and the through groove is located directly below the adhesive application position.

[0023] By adopting the above technical solution, the adhesive further reduces the probability of the temporary matching part springing out of the installation position. At the same time, by opening through grooves, the adhesive application position does not contact the slide rail, which greatly improves the situation of the temporary matching part sticking to the inner bottom wall of the slide rail.

[0024] Preferably, a slider is fixed to the inclined upper end of the slide rail, the slider is slidably connected to the top of the mounting base, a screw is longitudinally rotatably connected to the top of the mounting base, the screw thread passes through the slider, and a driving component that drives the screw to rotate is installed on the mounting base.

[0025] By adopting the above technical solution, the temporary matching part feeding operation was automated and the feeding position was accurate. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the state before material placement in a segmental prefabrication construction method for a cable-stayed bridge segmental steel box girder according to an embodiment of this application.

[0027] Figure 2 yes Figure 1 Enlarged diagram of point A in the middle.

[0028] Figure 3 This is a schematic diagram of the sliding rail structure in a segmental prefabrication construction method for a cable-stayed bridge segmental steel box girder according to an embodiment of this application.

[0029] Figure 4 This is a structural schematic diagram of the material placement process in a segmental prefabrication construction method for a cable-stayed bridge segmental steel box girder according to an embodiment of this application.

[0030] Figure 5 This is a schematic diagram of the structure after material placement in a segmental prefabrication construction method for a cable-stayed bridge segmental steel box girder according to an embodiment of this application.

[0031] Explanation of reference numerals in the attached drawings: 1. Standard segment; 11. Welding module; 2. Jig; 21. Mounting base; 3. Drive component; 4. Screw; 5. Slide rail; 51. Inclined storage section; 511. Slider; 512. Through groove; 52. Horizontal buffer section; 521. Drop port; 6. L-shaped plate; 61. Vertical plate; 62. Horizontal plate; 63. Bolt; 7. Cylinder; 71. Electromagnet. Detailed Implementation

[0032] The following is in conjunction with the appendix Figure 1-5 This application will be described in further detail.

[0033] This application discloses a method for segmental prefabrication of segmental steel box girders for cable-stayed bridges, referring to... Figure 1 This includes the following steps:

[0034] S1: Construction Preparation: The standard segment 1 is divided into three weldable modules 11 laterally for fabrication. Temporary matching parts are made, and a jig 2 is erected in the pre-assembly yard, with the length of the jig 2 as the longitudinal direction. The jig 2 is used to place the three weldable modules 11 laterally to assemble the standard segment 1 of the steel box girder, and the jig 2 is used to assemble several standard segments 1 longitudinally to assemble the composite beam segment.

[0035] Additionally, mounting seats 21 are installed on both sides of the jig 2, and slide rails 5 are slidably connected to the upper ends of both mounting seats 21. The slide rails 5 are used for connecting temporary matching parts. Specifically, a slider 511 is fixed to the inclined upper end of the slide rail 5. The slider 511 is slidably connected to the top of the mounting seat 21. A screw 4 is longitudinally rotatably connected to the top of the mounting seat 21, and the screw 4 is threaded through the slider 511. A driving component 3 is installed on the mounting seat 21 to drive the screw 4 to rotate. The driving component 3 is a motor, and the motor output shaft is coaxially connected to the screw 4. This automates the temporary matching part feeding operation and ensures accurate feeding position.

[0036] The two slide rails 5 are inclined downwards at the trisection points of the standard segment 1 to allow movement using the weight of the temporary matching parts. Specifically, the slide rail 5 includes an inclined storage section 51 and a horizontal buffer section 52. The horizontal buffer section 52 is located at the lower inclined end of the inclined storage section 51 and has a discharge port 521 located directly above the trisection points of the standard segment 1. The inclined storage section 51 not only serves as a guide but also has a storage function. The discharge port 521 in the horizontal buffer section 52 allows for continuous material discharge, eliminating the need for workers to carry temporary matching parts and simplifying the positioning operation of the temporary matching parts, thus reducing the workload of workers.

[0037] To improve the applicability of temporary mating parts to the welding module 11 and the adaptability of slide rail 5 to the temporary mating parts, the temporary mating parts used between adjacent welding modules 11 and the temporary mating parts used between adjacent standard segments 1 are customized to have the same structure.

[0038] Specifically, the temporary matching component includes two L-shaped plates 6, each corresponding to one of two adjacent welding modules 11. The two L-shaped plates 6 are attached to each other and fixed with bolts 63. Each L-shaped plate 6 includes vertical plates 61 and horizontal plates 62 that are perpendicular to each other. In the same temporary matching component, the two vertical plates 61 abut against each other, and the two horizontal plates 62 are joined to form a square base plate adapted to the width of the slide rail 5. Furthermore, every two temporary matching components used between adjacent welding modules 11, a temporary matching component is provided between adjacent standard segments 1. The two types of temporary matching components have the same structure, differing only in their placement.

[0039] To reduce the risk of the component springing out of its mounting position due to collision, a cylinder 7 is installed at the lower inclined end of the slide rail 5, and an electromagnet 71 is installed at the end of the cylinder 7. The L-shaped plate 6 is made of iron. By extending and retracting the cylinder 7 and energizing and de-energizing the electromagnet 71, the temporary matching component can be restricted and pulled, allowing it to fall vertically from a stationary state to its corresponding mounting position. Additionally, it is necessary to ensure that the distance between the bottom wall of the horizontal buffer section 52 and the upper surface of the welding module 11 is greater than the height of the vertical plate 61.

[0040] To further reduce the probability of the temporary matching part springing out of the installation position, a through groove 512 is provided at the bottom of the slide rail 5. The through groove 512 extends along the length of the slide rail 5 and communicates with the material drop port 521. Then, adhesive is applied to the bottom of the horizontal plate 62. The through groove 512 is located directly below the adhesive application position, so that the adhesive application position does not contact the slide rail 5, which greatly improves the situation of the temporary matching part being stuck to the inner bottom wall of the slide rail 5.

[0041] In step S2, during the unlocking step of the temporary matching component in step S3, the bolt 63 between the two L-shaped plates 6 is removed to disconnect the adjacent welding modules 11.

[0042] S2: Steel Box Girder Pre-assembly: Three welded modules 11 are hoisted and placed horizontally on the jig 2 and aligned to complete the positioning step of a set of standard segments 1 to be assembled; the positioning step of standard segments 1 to be assembled is repeated to complete the positioning step of the composite beam segment. Then, temporary matching parts are used to match the three welded modules 11 into standard segments 1, and multiple standard segments 1 are matched into a steel box girder composite segment.

[0043] Specifically, by starting the motor, the two sets of slide rails 5 are moved to the designated position, with the material drop port 521 located directly above the temporary matching part installation position. At this time, the lowest temporary matching part is blocked by the cylinder 7 and the electromagnet 71, and remains in the horizontal buffer section 52.

[0044] The L-shaped plate 6 is magnetically fixed by an electromagnet 71. Then, the cylinder 7 retracts, pulling the temporary matching parts to the material drop port 521. The electromagnet 71 is then de-energized, releasing the temporary matching parts, which fall vertically from a stationary state to their corresponding installation positions. The two temporary matching parts are then adhered to their respective welding modules 11. Before complete adhesion, workers can fine-tune the positions of the temporary matching parts to reduce errors before welding and reinforcing the welding modules 11 and the corresponding L-shaped plates 6.

[0045] The slide rail 5 moves longitudinally and the material dropping step is repeated to achieve the positioning of temporary matching parts between adjacent welding modules 11 and between adjacent standard segments 1, which helps to improve the overall installation efficiency of temporary matching parts.

[0046] S3: Transfer of welding module 11: Disconnect the temporary matching parts, leaving a set of standard segments 1 at the last end of the jig 2. Use the beam transport vehicle to transfer the remaining welding modules 11 one by one to the next construction area, and move the set of standard segments 1 at the last end of the jig 2 to the front end of the jig 2.

[0047] S4: Repeat S2 and S3 to complete the segmented prefabrication of the steel box girder.

[0048] After the prefabrication of the steel box girder is completed, the welding module 11 is transferred to the bridge deck and assembled into standard segment 1 on the bridge deck, and then the overall construction of the steel box girder on the bridge deck is carried out.

[0049] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for prefabricating segmental steel box girders for cable-stayed bridges, characterized in that: Includes the following steps: S1: Construction preparation: Divide the standard segment (1) into three welding modules (11) laterally for fabrication, make temporary matching parts, and set up a jig (2) in the pre-assembly yard; S2: Steel box girder pre-assembly: three welded modules (11) are hoisted in sequence, and the three welded modules (11) are placed horizontally on the jig (2) and aligned to complete the positioning step of a set of standard segments (1) to be assembled; the positioning step of standard segments (1) to be assembled is repeated, and then the three welded modules (11) are matched into standard segments (1) using temporary matching parts, and multiple standard segments (1) are matched into a steel box girder composite segment; S3: Transfer of welding module (11): Release the temporary matching part connection, leave the set of standard segments (1) at the last end of the jig (2), use the beam transport vehicle to transfer the remaining welding modules (11) one by one to the next construction area, and move the set of standard segments (1) at the last end of the jig (2) to the front end of the jig (2). S4: Repeat S2 and S3 to complete the segmented prefabrication of the steel box girder; In S1, mounting seats (21) are installed on both sides of the frame (2), and slide rails (5) are slidably connected to the upper ends of the two mounting seats (21). The slide rails (5) are used for temporary matching parts to connect. The two slide rails (5) are respectively inclined downwards towards the three division points of the standard segment (1).

2. The method for segmental prefabrication of segmental steel box girders for cable-stayed bridges according to claim 1, characterized in that: The slide rail (5) includes an inclined storage section (51) and a horizontal buffer section (52). The horizontal buffer section (52) is located at the inclined lower end of the inclined storage section (51). The horizontal buffer section (52) is provided with a discharge port (521), which is located directly above the trisection point of the standard segment (1).

3. The method for segmental prefabrication of segmental steel box girders for cable-stayed bridges according to claim 2, characterized in that: The temporary matching component includes two L-shaped plates (6), which correspond one-to-one with two adjacent welding modules (11). The two L-shaped plates (6) are attached to each other and fixed by bolts (63). In step S2, the temporary matching component is lowered to the joint of the adjacent welding modules (11) via a slide rail (5), and then the two L-shaped plates (6) of the temporary matching component are fixed to the upper surface of the corresponding welding modules (11). In the unlocking step of the temporary matching component in step S3, the bolts (63) between the two L-shaped plates (6) are removed to disconnect the adjacent welding modules (11).

4. The method for segmental prefabrication of segmental steel box girders for cable-stayed bridges according to claim 3, characterized in that: The L-shaped plate (6) includes vertical plates (61) and horizontal plates (62) that are perpendicular to each other. In the same temporary matching piece, two vertical plates (61) abut against each other, and two horizontal plates (62) are assembled to form a square base plate that fits the width of the slide rail (5). In S1, the temporary matching piece is stored in the inclined storage section (51) of the slide rail (5). The temporary matching piece between adjacent welding modules (11) has the same structure as the temporary matching piece between adjacent standard sections (1). In the inclined storage section (51), every two temporary matching pieces between adjacent welding modules (11) are set up with one temporary matching piece between adjacent standard sections (1). In S2, the slide rail (5) moves longitudinally and releases the temporary matching pieces one by one.

5. The method for segmental prefabrication of segmental steel box girders for cable-stayed bridges according to claim 4, characterized in that: A cylinder (7) is provided at the inclined lower end of the slide rail (5), and an electromagnet (71) is provided at the end of the cylinder (7). The L-shaped plate (6) is made of iron. In step S2, during the process of the slide rail (5) moving to the designated position, the electromagnet (71) is energized and magnetically fixes the L-shaped plate (6). When the slide rail (5) is in the designated position, the cylinder (7) retracts and uses the electromagnet (71) to attract the temporary matching part to the material drop port (521). When the material is dropped, the electromagnet (71) is de-energized and releases the temporary matching part, which falls vertically to the corresponding installation position.

6. The method for segmental prefabrication of segmental steel box girders for cable-stayed bridges according to claim 5, characterized in that: The slide rail (5) has a through groove (512) at the bottom. The through groove (512) extends along the length of the slide rail (5) and communicates with the material discharge port (521). In S1, an adhesive is applied to the bottom of the horizontal plate (62), and the through groove (512) is located directly below the adhesive application position.

7. The method for segmental prefabrication of segmental steel box girders for cable-stayed bridges according to claim 6, characterized in that: The slide rail (5) has a slider (511) fixed at its inclined upper end. The slider (511) is slidably connected to the top of the mounting base (21). The top of the mounting base (21) is longitudinally rotatably connected to a screw (4). The screw (4) is threaded through the slider (511). The mounting base (21) is equipped with a driving component (3) that drives the screw (4) to rotate.

Images