Overhead intersection widening section girder erection construction method

Abstract

The invention relates to an elevated intersection widening section girder erection construction method. The method comprises the following steps that a bridge girder erection machine is installed on a small prefabricated box girder erected on an elevated main line; a tail supporting leg of the bridge girder erection machine is placed on the prefabricated small box girder, a front supporting leg of the bridge girder erection machine is placed on the first bent cap, the position of a middle supporting leg is adjusted, and the middle supporting leg is placed on the prefabricated small box girder; a truss girder on the bridge girder erection machine is moved forwards, and a front temporary supporting leg is placed on a second long bent cap; the supporting legs begin to be washed away before being folded; after washing is completed, a block-up device is placed on the first long bent cap, a truss girder on the bridge girder erection machine is moved forwards, and the whole bridge girder erection machine is moved to the intersection widening section of the cast-in-place box girder ramp and the main line prefabricated small box girder through a middle supporting leg and a front supporting leg; hoisting the pre-erected small box girder on the rear hoisting crown block and the front hoisting crown block through a steel wire rope, and placing the pre-erected small box girder on the intersection widening section; the construction efficiency is greatly improved, the construction progress is shortened, the construction cost is saved, and the construction progress is accelerated.

Description

Technical Field

[0001] This invention belongs to the field of bridge box girder erection technology in construction engineering, and particularly relates to a method for erecting girder in a widened section of an elevated intersection. Background Technology

[0002] During the construction of the viaduct, in the existing construction methods for the intersection and widening section of the elevated cast-in-place box girder ramp and the precast small box girder of the main line, the precast small box girders of the main line are usually hoisted into place by a bridge erecting machine first, and then the construction of the intersection and widening section of the elevated cast-in-place box girder ramp and the precast small box girder of the main line is carried out. In the process of handling the intersection and widening section, the ramp is first cast in place, and then the small box girders of the same height and length as the precast small box girders of the main line are erected. The erection process uses cranes, etc., which greatly prolongs the construction period and affects the construction progress. Our company uses a bridge erecting machine to construct the small box girder at the intersection with the precast small box girder of the main line, which is then widened. However, during the construction process, a middle support leg elevation device needs to be installed on the cap beam to enable the bridge erecting machine to erect the small box girder. The following method is usually used to address the issue of installing the middle support leg elevation device: 1. Sandbag / Sleeper Stack Method: Sandbags or sleeper stacks are piled up below the support point to elevate the foundation. This method has obvious drawbacks: poor stability, prone to compression settlement, resulting in unreliable support; uneven stress distribution, posing safety hazards; low construction efficiency, high material waste, and difficulty in accurately controlling the elevation.

[0003] 2. Simple steel welding method: I-beams or H-beams are cut and welded on-site to form a temporary support frame. Although this method improves strength, it carries the risk of on-site hot work, has a long construction period, and the support structure is for one-time use only, resulting in poor versatility and waste of materials and labor.

[0004] 3. Custom-designed outriggers: This method involves customizing extended or specially structured outriggers for specific projects. It is costly and uneconomical, and a single set of custom-designed outriggers cannot be applied to bridges with different spans or varying slopes, lacking versatility and flexibility.

[0005] Therefore, existing technologies lack a fast, safe, adjustable, reusable, and economical solution for raising the middle outriggers. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a method for constructing elevated interchange widening sections of beams that is efficient and convenient.

[0007] The objective of this invention is achieved through the following technical solution: a method for constructing bridge beams in a widening section at an elevated intersection, comprising the following steps: S1. Install the bridge erecting machine along the length of the elevated main line on the precast small box girder erected on the main line of the elevated structure. S2. Place the tail leg of the bridge erecting machine on the precast small box girder that has been erected, place the front leg of the bridge erecting machine on the No. 1 cap beam, suspend the front temporary leg in the air, adjust the position of the middle leg and move it forward to a position about 5m in front of the precast small box girder that has been erected and place it on the precast small box girder. S3. Move the truss beam on the bridge erecting machine forward and place the front temporary support leg on the No. 2 long cover beam; S4. Retract the front outriggers and begin the collapse, suspending the front outriggers between the No. 1 long cap beam and the No. 2 long cap beam. S5. The breaching is complete, and a shim is placed on the side of the precast small box girder on the No. 1 long cap beam. S6. Adjust the height of the shim device so that it is flush with the height of the precast small box girder, and extend the guide rail that moves in conjunction with the middle support leg and place it on the shim device. S7. Move the truss beam on the bridge erecting machine forward, and move the rear and front cranes forward, and move the entire bridge erecting machine to the widening section where the cast-in-place box girder ramp intersects with the precast small box girder of the main line via the middle and front legs. S8. The small box girder is pre-erected by lifting it on the rear crane and the front crane using steel wire ropes, and the pre-erected small box girder is placed on the intersection widening section between the No. 1 long cap beam and the No. 2 long cap beam. S9. Cast a cast-in-place box girder again between the No. 1 long cap beam and the No. 3 long cap beam, and make the cast-in-place box girder flush with the ramps of the cast-in-place box girder and the several pre-erected small box girders that have been placed.

[0008] The beneficial effects of this invention are as follows: Compared with the prior art, by installing a bridge erecting machine on the precast small box girders erected on the elevated main line, placing a shim on the No. 1 long cap beam near the side of the cast-in-place box girder ramp, and extending the guide rail that moves in coordination with the middle support leg and placing it on the shim, several precast small box girders are placed on the intersection widening section by the bridge erecting machine. This allows the erection of precast small box girders on the main line and the intersection widening section to be completed by one bridge erecting machine. After the erection of the precast small box girders on the intersection widening section is completed, the erection of the precast small box girders on the main line can be carried out immediately, and the implementation of step S9 can be carried out simultaneously. This greatly improves the construction efficiency, shortens the construction process, saves construction costs, and speeds up the construction progress.

[0009] Preferably, in step S5, several elevation devices are provided and placed at equal intervals along the length of the first long cap beam, with one side of each elevation device flush with the end face of the precast small box girder along its length. The equal-interval placement of the elevation devices makes the force distribution more uniform, thereby improving the load-bearing stability of the extended section of the guide rail that moves in conjunction with the middle support leg. At the same time, the flushness of one side of each elevation device with the end face of the precast small box girder along its length ensures that the precast small box girder is flush with the precast small box girder erected on the elevated main line. This ensures that the connection joint between the intersection and widening section of the elevated main line and the cast-in-place box girder ramp is consistent with the connection joint between adjacent small box girders on the main line, which facilitates subsequent construction and maintenance.

[0010] As a preferred option, in step S8, the entire bridge erecting machine sequentially places pre-erected small box girders along the length of the first and second long cap beams at the intersection widening section, and the entire bridge erecting machine moves sequentially along the placement direction until the placed pre-erected small box girders are the same width as the ramp with the already cast-in-place box girder. Through the above construction steps, it is convenient to pour the cast-in-place box girder between the placed pre-erected small box girders and the ramp with the already cast-in-place box girder (i.e., step S9), and the pouring and splicing can be completed during the pouring process in step S9, making construction more convenient and greatly improving construction efficiency.

[0011] Preferably, the elevation device includes a bottom sealing cylinder and a support cylinder; the lower end of the support cylinder is provided with a support plate, which is sleeved on the inner wall of the bottom sealing cylinder and can slide up and down. Fine sand is filled into the cavity between the bottom sealing cylinder and the support plate. A bearing component is provided between the upper end of the support cylinder and the lower end of the bottom sealing cylinder, and the bearing components are fixed together by connecting components. A sand discharge component is provided at the bottom of the side wall of the bottom sealing cylinder to facilitate the discharge of fine sand. The sand discharge component is set obliquely downward along the height direction of the bottom sealing cylinder. By using the cooperation of the bottom sealing cylinder and the support cylinder, and filling the cavity between the bottom sealing cylinder and the support plate with fine sand, the stability and load-bearing capacity of the entire support system are ensured, the safety risks are greatly reduced, and it also has the advantages of being height-adjustable, reusable, requiring no open flame, and easy to disassemble and assemble. The sand discharge component is set obliquely downward along the height direction of the bottom sealing cylinder, which facilitates the discharge of fine sand in the bottom sealing cylinder through this structure, thus making it easy to fine-tune the height difference between the support cylinder and the bottom sealing cylinder.

[0012] Preferably, the sand discharge assembly includes a sand discharge pipe and a cap nut. One end of the sand discharge pipe is fixed and connected to a through hole opened at the bottom of the side wall of the bottom sealing cylinder, and the other end of the sand discharge pipe is provided with an external thread and is tightened and fixed with the cap nut. The sand discharge pipe is set obliquely downward along the height direction of the bottom sealing cylinder. With the above structure, the height difference between the support cylinder and the bottom sealing cylinder can be finely adjusted by controlling the amount of fine sand discharged. At the same time, setting the sand discharge pipe obliquely downward along the height direction of the bottom sealing cylinder not only facilitates the above-mentioned fine adjustment function, but also allows most of the sand to be discharged through the sand discharge pipe after the entire device is used up, which is convenient for disassembly.

[0013] Preferably, the load-bearing component includes a top cover plate and a bottom support plate. The top cover plate is fixed to the upper end of the support cylinder, and the bottom support plate is fixed to the lower end of the bottom sealing cylinder. Both the top cover plate and the bottom support plate are rectangular and have the same area. The above structure makes the device more stable during the support process.

[0014] Preferably, the connecting assembly includes screws and bolts. There are four screws that pass through the bottom support plate to the top cover plate, and the bolts are tightened with the screws and fixed to the top cover plate. With the above structure, after the height of the device is adjusted, it is easy to tighten and fix the bolts and screws, and disassembly and assembly are more convenient.

[0015] Preferably, the bottom support plate is provided with a countersunk hole, and the screw head of the screw is embedded in the countersunk hole, with the bottom of the screw head flush with the bottom surface of the bottom support plate. Because the screw head of the screw is located at the bottom of the bottom support plate, the above structure ensures that the screw head will not come into contact with the concrete block below the bottom support plate, resulting in a larger bearing area and better stability.

[0016] Preferably, the connecting components are located at the four corners of the top cover plate and the bottom support plate, and the spacing between adjacent screws is greater than the width of the guide rail of the bridge erecting machine; this allows the guide rail to rest completely on the top cover plate, resulting in more stable force distribution. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of step S1 of the construction method of the present invention.

[0018] Figure 2 This is a schematic diagram of the main structure of step S1 of the construction method of the present invention.

[0019] Figure 3 This is a schematic diagram of the main structure of the construction method S2-S3 of the present invention.

[0020] Figure 4 This is a schematic diagram of the construction method S4 of the present invention.

[0021] Figure 5 This is a schematic diagram of the construction method S5-S6 of the present invention.

[0022] Figure 6 These are schematic diagrams of the main structure of the construction method S7-S9 of the present invention.

[0023] Figure 7 These are top view structural diagrams of the construction methods S7-S9 of this invention.

[0024] Figure 8 This is a three-dimensional structural diagram of the elevation device of the present invention.

[0025] Figure 9 This is a schematic diagram of the main structure of the elevation device of the present invention.

[0026] Figure 10 This is a schematic diagram of the structure of the elevation device of the present invention on the cover beam.

[0027] The labels in the attached diagram are as follows: 1. Concrete pad block; 2. No. 1 long cap beam; 3. Precast small box girder; 4. Bridge erecting machine; 5. No. 2 long cap beam; 6. Guide rail; 7. Elevation device; 8. Rear crane; 9. Front crane; 10. Intersection widening section; 11. Pre-erected small box girder; 12. No. 3 long cap beam; 13. Cast-in-place box girder ramp; 14. Pier; 15. Abutment; 16. Pile; 41. Tail support leg; 42. Front support leg; 43. Front temporary support leg; 44. Middle support leg; 100. Bottom sealing cylinder; 101. Support cylinder; 102. Support plate; 200. Bearing component; 201. Top cover plate; 202. Bottom support plate; 203. Countersunk hole; 300. Connecting component; 301. Screw; 302. Bolt; 303. Screw head; 400. Sand discharge assembly; 401. Sand discharge pipe; 402. Cap nut. Detailed Implementation

[0028] The invention will now be described in detail with reference to the accompanying drawings: as shown in the drawings Figures 1 to 7 As shown, the construction method of the present invention includes the following steps: S1. Install the bridge erecting machine 4 along the length of the elevated main line on the precast small box girder 3 that has been erected. S2. Place the tail support leg 41 of the bridge erecting machine 4 on the precast small box girder 3 that has been erected, place the front support leg 42 of the bridge erecting machine 4 on the No. 1 long cover beam 2, suspend the front temporary support leg 43, adjust the position of the middle support leg 44 and move it forward to a position about 5m in front of the precast small box girder 3 that has been erected and place it on the precast small box girder 3. S3, move the truss beam on the bridge erecting machine 4 forward and place the front temporary support leg 43 on the second long cap beam 5; S4. Retract the front support leg 42 to begin the collapse, and suspend the front support leg 42 between the No. 1 long cover beam 2 and the No. 2 long cover beam 5. S5. After the collapse is completed, a lifting device 7 is placed on the side of the precast small box beam 3 on the first long cover beam 2, and the front support leg 42 is placed on the guide rail on the second long cover beam 5. S6. Adjust the height of the shim 7 so that the height of the shim 7 is flush with the height of the precast small box girder 3, and extend the guide rail 6 that moves in coordination with the middle support leg 44 and place it on the shim 7. S7, the truss beam on the forward-moving bridge erecting machine 4, and the forward-moving rear crane 8 and front crane 9, and move the entire bridge erecting machine 4 to the intersection and widening section 10 of the cast-in-place box girder ramp 13 and the main line precast small box girder 3 through the middle support leg 44 and the front support leg 42. S8. The small box girder 11 is pre-erected by lifting it on the rear crane 8 and the front crane 9 using wire ropes, and the pre-erected small box girder 11 is placed on the intersection widening section 10 between the No. 1 long cap beam 2 and the No. 2 long cap beam 5. S9. Cast a cast-in-place box girder again between the No. 1 long cap beam 2 and the No. 3 long cap beam 12, and the cast-in-place box girder is flush with the already cast-in-place box girder ramp 13 and the several pre-erected small box girders 11.

[0029] In step S5, several shim devices 7 are provided and are placed at equal intervals along the length of the first long cover beam 2, and one side of each shim device 7 is flush with the end face of the precast small box girder 3 along its length.

[0030] In step S8, the entire bridge erecting machine 4 sequentially places pre-erected small box girders 11 along the length direction of the first long cap beam 2 and the second long cap beam 5 in the intersection widening section 10, and the entire bridge erecting machine 4 moves sequentially along the placement direction until the placed pre-erected small box girders 11 are the same width as the cast-in-place box girder ramp 13.

[0031] The No. 1 long cap beam 2, the No. 2 long cap beam 5, and the No. 3 long cap beam 12 are all supported by piers 14, pile caps 15, and piles 16.

[0032] As attached Figures 8 to 10 As shown, the elevation device 7 includes a bottom sealing cylinder 100 and a support cylinder 101; the lower end of the support cylinder 101 is provided with a support plate 102, which is sleeved on the inner wall of the bottom sealing cylinder 100 and can slide up and down. The outer diameter of the support plate 102 is smaller than the inner diameter of the bottom sealing cylinder 100. Fine sand is filled into the cavity between the bottom sealing cylinder 100 and the support plate 102. A bearing assembly 200 is provided between the upper end of the support cylinder 101 and the lower end of the bottom sealing cylinder 100, and the bearing assemblies 200 are fixed together by a connecting assembly 300. A sand discharge assembly 400 is provided at the bottom of the side wall of the bottom sealing cylinder 100 to facilitate the discharge of fine sand. The sand discharge assembly 400 is obliquely downward along the height direction of the bottom sealing cylinder 100.

[0033] The structure and arrangement of the above-mentioned elevation device have the following advantages: 1. Provide a modular and standardized elevation device that enables rapid assembly and disassembly, thereby improving construction efficiency.

[0034] 2. Ensure the rigidity and stability of the support system, effectively distribute concentrated loads, and guarantee the safety of the bridge erecting machine during beam erection operations in the widening section.

[0035] 3. It has adjustable height and planar dimensions, which can flexibly adapt to the needs of different slopes and different support positions, and has strong versatility.

[0036] 4. Reduce on-site welding and cutting operations, lower safety risks, and the equipment can be reused, saving project costs.

[0037] The sand discharge assembly 400 includes a sand discharge pipe 401 and a cap nut 402. One end of the sand discharge pipe 401 is fixed and connected to a through hole opened at the bottom of the side wall of the bottom sealing cylinder 100. The other end of the sand discharge pipe 401 is provided with an external thread and is screwed and fixed to the cap nut 402. The sand discharge pipe 401 is arranged obliquely downward along the height direction of the bottom sealing cylinder 100.

[0038] The load-bearing component 200 includes a top cover plate 201 and a bottom support plate 202. The top cover plate 201 is fixed to the upper end of the support cylinder 101, and the bottom support plate 202 is fixed to the lower end of the bottom sealing cylinder 100. Both the top cover plate 201 and the bottom support plate 202 are rectangular and have the same area.

[0039] The connecting assembly 300 includes screws 301 and bolts 302. There are four screws 301 that pass through the bottom support plate 202 to the top cover plate 201, and the bolts 302 are tightened with the screws 301 and fixed to the top cover plate 201.

[0040] The bottom support plate 202 is provided with a countersunk hole 203, and the screw head 303 of the screw 301 is embedded in the countersunk hole 203, and the bottom of the screw head 303 is flush with the bottom surface of the bottom support plate 202.

[0041] The connecting components 300 are all located at the four corners of the top cover plate 201 and the bottom support plate 202, and the spacing between adjacent screws 301 is greater than the width of the guide rail 6 of the bridge erecting machine.

[0042] The bottom sealing cylinder 100 rests on the concrete pad 1 via the bottom support plate 202, and the concrete pad 1 rests on the first long cap beam 2.

[0043] The working principle of this shim device 7 is as follows: First, the screw 301 is passed through the bottom support plate 202, and the screw head 303 is embedded in the countersunk hole 203. Then, fine sand is poured into the bottom sealing cylinder 100, and the support plate 102 of the support cylinder 101 is pressed on the fine sand and the height is measured to see if the required height is reached. Finally, the bolts 302 are tightened to the screw 301, and the flatness of the top cover plate 201 is adjusted.

[0044] Compared with existing technologies, this elevation device 7 has the following significant advantages: 1. Safe and reliable: The rigid structure of the middle outrigger elevation device ensures the stability and load-bearing capacity of the entire support system, greatly reducing safety risks.

[0045] 2. High efficiency and convenience: The standardized components can be assembled and disassembled quickly without the need for on-site hot work, which significantly improves construction efficiency and shortens the construction period.

[0046] 3. Flexible and Adjustable: It achieves stepless fine-tuning of the elevation height, which can accurately meet the complex elevation changes required in widening sections. The length and dimensions of the foundation support concrete blocks and the top cover plate of the elevation device can be flexibly selected according to the actual working conditions, making it highly versatile.

[0047] 4. Economic and environmentally friendly: All components of the device can be reused in different parts of the same project or different projects, which greatly reduces the consumption of disposable materials such as sandbags and sleepers in traditional methods, reduces project costs, and conforms to the concept of green construction.

[0048] 5. Quality control: Standardized construction process reduces human interference, and precise control of support elevation helps ensure the alignment quality and construction accuracy of the beam erection.

[0049] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for constructing bridge beams on a widening section of an elevated interchange, characterized in that: The construction method includes the following steps: S1. Install the bridge erecting machine along the length of the elevated main line on the precast small box girder erected on the main line of the elevated structure. S2. Place the tail leg of the bridge erecting machine on the precast small box girder that has been erected, place the front leg of the bridge erecting machine on the No. 1 long cover beam, suspend the front temporary leg in the air, adjust the position of the middle leg and move it forward to a position about 5m in front of the precast small box girder that has been erected and place it on the precast small box girder. S3. Move the truss beam on the bridge erecting machine forward and place the front temporary support leg on the No. 2 long cap beam; S4. Retract the front outriggers and begin the collapse, suspending the front outriggers between the No. 1 long cap beam and the No. 2 long cap beam. S5. The breaching is complete, and a shim is placed on the side of the precast small box girder on the No. 1 long cap beam. S6. Adjust the height of the shim device so that it is flush with the height of the precast small box girder, and extend the guide rail that moves in conjunction with the middle support leg and place it on the shim device. S7. Move the truss beam on the bridge erecting machine forward, and move the rear and front cranes forward, and move the entire bridge erecting machine to the widening section where the cast-in-place box girder ramp intersects with the precast small box girder of the main line via the middle and front legs. S8. The small box girder is pre-erected by lifting it on the rear crane and the front crane using wire ropes, and the pre-erected small box girder is placed on the intersection widening section between the No. 1 long cap beam and the No. 2 long cap beam. S9. Cast a cast-in-place box girder again between the No. 1 long cap beam and the No. 3 long cap beam, and make the cast-in-place box girder flush with the ramps of the cast-in-place box girder and the several pre-erected small box girders that have been placed.

2. The method for constructing beams in the elevated intersection widening section according to claim 1, characterized in that: In step S5, several elevation devices are provided and are placed at equal intervals along the length of the first long cap beam, with one side of each elevation device flush with the end face of the precast small box girder along its length.

3. The method for constructing bridge beams at elevated intersections with widening sections according to claim 1, characterized in that: In step S8, the entire bridge erecting machine sequentially places pre-erected small box girders along the length of the No. 1 and No. 2 long cap beams in the intersection widening section, and the entire bridge erecting machine moves sequentially along the placement direction until the placed pre-erected small box girders are the same width as the cast-in-place box girder ramp.

4. The method for constructing bridge beams at elevated intersections with widening sections according to claim 1, characterized in that: The elevation device includes a bottom sealing cylinder and a support cylinder; the lower end of the support cylinder is provided with a support plate, which is sleeved on the inner wall of the bottom sealing cylinder and can slide up and down. Fine sand is filled into the cavity between the bottom sealing cylinder and the support plate. A bearing component is provided between the upper end of the support cylinder and the lower end of the bottom sealing cylinder, and the bearing components are fixed together by a connecting component. A sand discharge component is provided at the bottom of the side wall of the bottom sealing cylinder to facilitate the discharge of fine sand. The sand discharge component is set obliquely downward along the height direction of the bottom sealing cylinder.

5. The method for constructing beams in the elevated intersection widening section according to claim 4, characterized in that: The sand discharge assembly includes a sand discharge pipe and a cap nut. One end of the sand discharge pipe is fixed and connected to a through hole opened at the bottom of the side wall of the bottom sealing cylinder. The other end of the sand discharge pipe is provided with an external thread and is tightened and fixed with the cap nut. The sand discharge pipe is set obliquely downward along the height direction of the bottom sealing cylinder.

6. The method for constructing bridge beams at elevated intersections with widening sections according to claim 4, characterized in that: The load-bearing components include a top cover plate and a bottom support plate. The top cover plate is fixed to the upper end of the support cylinder, and the bottom support plate is fixed to the lower end of the bottom sealing cylinder. Both the top cover plate and the bottom support plate are rectangular and have the same area.

7. The method for constructing beams on the elevated intersection widening section according to claim 6, characterized in that: The connecting assembly includes screws and bolts. There are four screws that pass through the bottom support plate to the top cover plate, and the bolts are tightened with the screws and fixed to the top cover plate.

8. The method for constructing beams at elevated intersection widening sections according to claim 7, characterized in that: The bottom support plate has a countersunk hole, and the screw head of the screw is embedded in the countersunk hole, with the bottom of the screw head flush with the bottom surface of the bottom support plate.

9. The method for constructing beams on the elevated intersection widening section according to claim 6, characterized in that: The connecting components are all located at the four corners of the top cover plate and the bottom support plate, and the spacing between adjacent screws is greater than the width of the bridge erecting machine's guide rail.

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