A method for rectifying the diseases of the abutment of a highway bridge spanning an existing railway

Abstract

The present invention discloses a method for rectifying the diseases of the abutment of a highway bridge spanning an existing railway. During the rectification process, first, the beam body of the highway bridge is hoisted onto the existing highway and placed. The part of the abutment with diseases and affecting the safety of the existing railway is demolished. A cross beam is constructed on the pile foundation. Utilizing the railway skylight time, the precast slab beam and the beam body are hoisted onto the cross beam, and the slab beam is located on the demolished abutment. Finally, the bridge deck pavement is constructed to complete the rectification of the diseased highway bridge. By using the method of the present invention, the pile foundation can be constructed before the abutment is demolished, without affecting the operation of the highway bridge. When demolishing the abutment, only the part with diseases and affecting the safety of the existing railway needs to be demolished, reducing the demolition of the existing abutment. At the same time, the excavation and backfilling of the subgrade behind the highway abutment are reduced, accelerating the construction speed, minimizing the impact on the traffic of the highway bridge during the integration and rectification process, and reducing the demolition of the existing abutment and the bearing platform can save investment.

Description

Technical Field

[0001] The present invention relates to the technical field of highway bridge construction, and particularly relates to a method for rectifying diseases of the abutment of a highway bridge spanning an existing railway. Background Art

[0002] With the economic development of our country, transportation has become more and more developed. The intersection of railways and highways has become relatively common. Usually, railways cross highways, but in special cases, it is inevitable for highways to cross railways. Especially for the ordinary-speed railways designed in the last century and the beginning of this century, there are many highway bridges spanning railways. Under the long-term action of loads, diseases will occur in the abutments of highway bridges. Diseases of the abutments such as cracks, concrete spalling, and even inclination. Cracks appear in the abutments as Figure 1 shown. The occurrence of these diseases affects the safety of railways and highways, and it is necessary to reinforce and reconstruct the highway bridge. During the reinforcement or reconstruction process, it is necessary to minimize the impact on the existing operating railway and highway traffic, and save investment as much as possible.

[0003] Reinforcement is to reinforce the structure of the highway bridge when the diseases are relatively small and will not cause the safety of the highway bridge. When the diseases are relatively serious, it is necessary to reconstruct the highway bridge. The existing reconstruction plan first suspends the traffic on the bridge, uses a crane to lift the existing highway bridge body to both sides of the highway during the skylight time, and then gradually demolishes the existing abutment, bearing platform, and subgrade behind the abutment. Since it is close to the operating line, large machinery cannot be used for demolition, and small tools need to be used for demolition; after the demolition is completed, the construction of the pile foundation, bearing platform, pier, and subgrade behind the abutment of the new highway bridge is carried out step by step, and the beam part is hoisted by a crane during the skylight time, and the construction is completed. The existing disease reconstruction method needs to demolish the original abutment and then build a new one, which has a large workload, a long construction time, a large investment, and a large economic loss. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for rectifying diseases of the abutment of a highway bridge spanning an existing railway, aiming at the problems of long construction time, large investment, and large economic loss of the existing disease reconstruction method, which demolishes less of the existing abutment and subgrade, saves investment and speeds up the project construction speed.

[0005] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0006] A method for rectifying diseases of the abutment of a highway bridge spanning an existing railway. There are two abutments of the highway bridge. A portal pier is constructed on the abutment, and the beam body of the highway bridge is transferred to the portal pier. The portal pier includes a pile foundation and a cross beam. The rectification method includes the following steps:

[0007] S1. Construct the pile foundations on both sides of the abutment along the bridge direction, and set a plurality of the pile foundations on both sides of each abutment;

[0008] S2. Utilize the railway's skylight time to lift the beam body of the highway bridge and place it on the existing highway.

[0009] S3. Demolish the part of the abutment that has diseases and affects the safety of the existing railway.

[0010] S4. Construct a crossbeam on the pile foundation. The crossbeam includes a first crossbeam and an ear platform crossbeam. The first crossbeam is placed on the pile foundation far from the existing highway, and the ear platform crossbeam is placed on the pile foundation close to the existing highway.

[0011] S5. Utilize the railway's skylight time to lift the precast slab beam and the beam body onto the crossbeam. The slab beam is located on the demolished abutment.

[0012] S6. Construct the bridge deck paving to complete the renovation of the diseased highway bridge.

[0013] Further, the detailed steps of S1 are as follows: Four pile foundations are set on both sides of each abutment. The four pile foundations are divided into two groups. The two pile foundations in the same group are symmetrically located on both sides of the abutment. One group of pile foundations is set on both sides of the abutment close to the existing highway, and one group of pile foundations is set on both sides of the abutment far from the existing highway. Construct the pile foundations on both sides of the abutment to the bottom of the portal pier.

[0014] Further, in step S3, when the center of the abutment is a hollow structure, demolishing the part of the abutment that has diseases and affects the safety of the existing railway means demolishing all the abutment above the bottom of the hollow structure of the abutment.

[0015] Further, the first crossbeam is a cuboid and is placed on the tops of two pile foundations symmetrically arranged on the abutment.

[0016] Further, the ear platform crossbeam includes a second crossbeam, a first ear plate, and a second ear plate. There are two first ear plates. The first ear plate and the second ear plate form a U shape for retaining soil.

[0017] Further, in step S5, before hoisting the slab beam and the beam body, first construct bearings on the crossbeam. There are multiple bearings, which are arranged at intervals on the crossbeam. Further, the bearings are rubber bearings.

[0018] Furthermore, there are also retaining blocks on the crossbeam. There are multiple retaining blocks, which are arranged at intervals along the length direction of the highway bridge on both sides of the slab beam or the beam body. The top surface of the retaining block is higher than the bottom surface of the slab beam or the beam body, and is used to limit the slab beam or the beam body to prevent the slab beam or the beam body from shifting.

[0019] Furthermore, when constructing the bridge deck pavement, auxiliary works and approach slabs also need to be constructed. The auxiliary works include bridge deck pavement, expansion joints, sidewalks, railings, anti-throw nets, etc. The approach slab is used to connect the beam body with the existing highway.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] The renovation method of the present invention can solve the situation where a highway bridge spanning a railway needs to be rebuilt due to diseases. The construction of the pile foundation can be carried out before the abutment is demolished, without affecting the operation of the highway bridge. Since it is close to the railway operating line, large machinery is not allowed to be used for demolishing the abutment and the bearing platform. When demolishing the abutment, only the part with diseases and affecting the safety of the existing railway needs to be demolished, reducing the demolition of the existing abutment. At the same time, the excavation and backfilling of the subgrade behind the highway abutment are reduced. The method of the present invention speeds up the construction speed, reduces the impact on the traffic of the highway bridge during the integration and renovation process, and the reduction of the demolition of the existing abutment and the bearing platform can save investment.

[0022] The renovation method of the present invention can be widely applied to highway bridges spanning existing railways that need to be renovated, shortening the impact on highway traffic and improving economy and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a field view of the highway bridge abutment with crack diseases in Embodiment 1;

[0024] Figure 2 It is a side view of the highway bridge in Embodiment 1;

[0025] Figure 3 It is a side view of the renovated highway bridge in Embodiment 1;

[0026] Figure 4 It is a top view of the construction of the portal pier in Embodiment 1;

[0027] Figure 5 It is a side view of the construction of the ear table cross beam in Embodiment 1;

[0028] Figure 6 It is a cross-sectional view of the construction of the slab beam in Embodiment 1;

[0029] Markings in the figure: 1 - railway line, 2 - beam body, 3 - bearing platform, 4 - abutment, 41 - abutment demolition line, 5 - slope protection structure, 6 - portal pier, 61 - pile foundation, 62 - first cross beam, 63 - ear table cross beam, 631 - first ear plate, 632 - second ear plate, 64 - bearing, 65 - stop block, 7 - slab beam, 8 - existing highway, 9 - approach slab. DETAILED DESCRIPTION OF THE INVENTION

[0030] The present invention will be further described in detail below in combination with engineering examples and specific implementation manners. However, it should not be understood that the scope of the above-mentioned subject matter of the present invention is limited to the following embodiments. All technologies implemented based on the content of the present invention belong to the scope of the present invention.

[0031] Embodiment 1

[0032] This embodiment takes the disease treatment of a highway bridge straddling a railway in the southwestern region as an example. The side view of the highway bridge is as shown in Figure 2 . The highway bridge includes a bearing platform 3, abutments 4, and a beam body 2. The bearing platform 3 is arranged on the roadbed. The bearing platform 3 includes a plurality of vertically arranged support piles and a foundation platform arranged on the top of the support piles. There are two abutments 4 in this embodiment. Slope protection structures 5 are arranged on both sides of the abutments 4. The slope protection structures 5 are usually soil slope protections. The abutments 4 are arranged on the bearing platform 3. A beam body 2 is arranged between the tops of the abutments 4. The beam body 2 connects the existing highways 8 on both sides of the highway bridge. The bottom of the existing highway 8 is the subgrade behind the abutment. Cracks running through the entire abutment 4 appear on the body of the abutment 4 of this highway bridge, and the crack width reaches 10 mm. As shown in Figure 1 , the existence of the cracks causes the bearing capacity of the abutment 4 to decline, affecting the traffic safety on the bridge. If the front wall of the abutment 4 overturns onto the railway, it will affect the railway operation under the bridge, and the existing highway 8 bridge needs to be reconstructed. The traditional renovation plan for highway bridge diseases is as follows: First, suspend the traffic on the bridge. Use a crane to lift the highway bridge beam body 2 onto the existing highways 8 on both sides during the skylight time, and then gradually demolish the abutments 4 and the bearing platform 3. Since the highway bridge in this embodiment is close to the operating railway line 1, large machinery cannot be used for demolition, and only small tools can be used for demolition. After the demolition is completed, gradually construct the new highway bridge bearing platform, pier, and subgrade behind the abutment, and use a crane to hoist the beam body during the skylight time to complete the construction. However, this method requires the demolition of the existing abutment,

[0033] In order to minimize the demolition and reconstruction of the existing highway 8 bridge and the subgrade behind the abutment, a method for treating diseases of the abutment of a highway bridge spanning an existing railway is proposed. There are two abutments 4 of the highway bridge with diseases. Construct a portal pier 6 on the abutment 4, and transfer the beam body 2 of the highway bridge to the portal pier 6. The portal pier 6 includes a pile foundation 61 and a cross beam. As shown in Figure 3 , the treatment method includes the following steps:

[0034] S1. Construct pile foundations 61 on both sides of the abutment 4 along the bridge direction, and set a plurality of pile foundations 61 on both sides of each abutment 4;

[0035] The detailed steps of S1 are as follows: Four pile foundations 61 are arranged on both sides of each abutment 4. The four pile foundations 61 are divided into two groups. The two pile foundations 61 in the same group are symmetrically located on both sides of the abutment 4. One group of pile foundations 61 is arranged on both sides of the abutment 4 close to the existing road 8, and one group of pile foundations 61 is arranged on both sides of the abutment 4 far from the existing road 8. The pile foundations 61 are constructed on both sides of the abutment 4 until the bottom of the portal pier. In this embodiment, there are two abutments 4 for the highway bridge, and one portal pier 6 is constructed on the side of each abutment 4.

[0036] S2. During the railway skylight time, lift the beam body 2 of the highway bridge onto the existing road 8 for placement;

[0037] In step S2, before hoisting the beam body 2, the traffic of the highway bridge needs to be interrupted. During the railway skylight time, use a crane to lift the original beam body 2 of the highway bridge onto the existing roads 8 on both sides. Clean and protect the hoisted beam body 2 so that this beam body 2 can be hoisted again.

[0038] S3. Demolish the part of the abutment 4 that has diseases and affects the safety of the existing railway;

[0039] Adopt a portal pier 6 to be erected on the existing abutment 4. Utilize the fact that the portal pier 6 can bear the force of the highway bridge beam body 2 to unload the load of the existing abutment 4. Only demolish the abutment body 4 that affects the railway safety. In this embodiment, the demolition is carried out according to the abutment demolition line 41 as shown. After demolition, retain the part of the abutment 4 that does not affect the railway safety, and do not demolish the subgrade behind the abutment. Since such demolition demolishes less of the existing abutment 4 and the subgrade, it saves investment and speeds up the project construction speed. The center of part of the abutment 4 is a hollow structure. When demolishing, demolish all of the abutment 4 above the bottom of the hollow structure of the abutment 4. After demolishing the abutment 4, tidy up the site for construction. Figure 3 As shown, after demolition, retain the part of the abutment 4 that does not affect the railway safety, and do not demolish the subgrade behind the abutment. Since such demolition demolishes less of the existing abutment 4 and the subgrade, it saves investment and speeds up the project construction speed. The center of part of the abutment 4 is a hollow structure. When demolishing, demolish all of the abutment 4 above the bottom of the hollow structure of the abutment 4. After demolishing the abutment 4, tidy up the site for construction.

[0040] S4. Construct a cross beam on the pile foundation 61. The cross beam includes a first cross beam 62 and an ear platform cross beam 63. The first cross beam 62 is placed on the pile foundation 61 far from the existing road 8. The first cross beam 62 is a cuboid and is placed on the tops of two pile foundations 61 symmetrically arranged on the abutment 4. The structure of the ear platform cross beam 63 is as shown. The ear platform cross beam 63 is placed on the pile foundation 61 close to the existing road 8. The ear platform cross beam 63 includes a second cross beam, a first ear plate 631, and a second ear plate 632. There are two first ear plates 631. The first ear plate 631 and the second ear plate 632 form a U shape, which plays a role in retaining soil and prevents the soil of the backstage subgrade from entering the ear platform cross beam 63 and affecting the construction of the slab beam 7, as shown in Figure 4 As shown, the ear platform cross beam 63 is placed on the pile foundation 61 close to the existing road 8. The ear platform cross beam 63 includes a second cross beam, a first ear plate 631, and a second ear plate 632. There are two first ear plates 631. The first ear plate 631 and the second ear plate 632 form a U shape, which plays a role in retaining soil and prevents the soil of the backstage subgrade from entering the ear platform cross beam 63 and affecting the construction of the slab beam 7, as shown in Figure 4 、 Figure 5 As shown.

[0041] S5. During the railway skylight time, lift the precast slab beam 7 and the beam body 2 onto the cross beam. The slab beam 7 is located above the demolished abutment 4.

[0042] The slab beam 7 is used for the overhead abutment 4 and is prefabricated in advance. The slab beam 7 is usually a hollow slab beam. After hoisting, the slab beam 7 is located above the demolished abutment 4. In this embodiment, two slab beams 7 are used. Each slab beam 7 is placed between the first cross beam 62 and the ear table cross beam 63 of the same abutment 4, and the beam body 2 is placed on the tops of the two first cross beams 62. In some embodiments, bearings 64 are constructed on the cross beams. There are multiple bearings 64, which are arranged on the cross beams at intervals. The bearings 64 are rubber bearings. Bearings 64 are provided on both the first cross beam 62 and the ear table cross beam 63. The arrangement of the bearings on the ear table cross beam 63 is as Figure 6 shown. Further, stoppers 65 are also provided on the cross beams. There are multiple stoppers 65, which are arranged at intervals along the length direction of the highway bridge on both sides of the slab beam 7 or the beam body 2. The top surface of the stopper 65 is higher than the bottom surface of the slab beam 7 or the beam body 2, and is used to limit the slab beam 7 or the beam body 2 to prevent the slab beam 7 or the beam body 2 from shifting.

[0043] S6. Construct the bridge deck pavement to complete the renovation of the diseased highway bridge.

[0044] In some embodiments, after the hoisting of the beam body 2 is completed, when constructing the bridge deck pavement, it is also necessary to construct auxiliary projects and the approach slab 9. The auxiliary projects include bridge deck pavement, expansion joint, sidewalk, railing, anti-throw net, etc. The approach slab 9 connects the slab beam 7 and the existing highway 8. The approach slab 9 is arranged on the subgrade adjacent to the abutment and is used to transition the uneven stiffness between the subgrade behind the abutment and the highway bridge.

[0045] In order to test the safety and feasibility of the present invention, stress simulation analyses are carried out on the slab beam, portal pier and pile foundation in the design. After analysis, the beam body, pier and foundation all meet the stress requirements of the highway bridge. The main limiting factor of this solution for renovating the diseased highway bridge by using the present invention is the lateral span between the portal piers of the two abutments. The width of the highway bridge in this embodiment is 7m, and the renovation method of the present invention can be adopted. According to the simulation analysis and calculation, the solution of the present invention can be adopted for highway bridges with a width of within 25m.

[0046] When the highway bridge spanning the railway has diseases and needs to be rebuilt, the renovation method of the present invention can speed up the construction speed. The construction pile foundation can be constructed before the abutment is demolished, without affecting the operation of the highway bridge. During the whole renovation process, the impact on the traffic of the highway bridge is small. The existing beam body can be utilized, saving investment. When demolishing the abutment, only the part with diseases and affecting the safety of the existing railway needs to be demolished, reducing the demolition of the existing abutment. Because it is close to the railway operating line, large machinery is not allowed to be used for demolishing the abutment and the bearing platform. Reducing the demolition of the existing abutment and the bearing platform can save investment. The excavation and backfilling of the subgrade behind the highway abutment are reduced. When backfilling the subgrade behind the abutment, it is impossible to roll the soil because the foundation pit is small, and expensive materials such as concrete need to be used for backfilling. The implementation of this scheme avoids the backfilling behind the abutment. Because the demolition of the abutment and the bearing platform and the backfilling behind the abutment take time, avoiding these works can speed up the construction speed of the highway bridge and reduce the impact on highway traffic. In this example, about 800,000 yuan of investment is saved and about 2 months of construction period is saved by adopting this scheme.

[0047] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for rectifying the diseases of the abutments of a highway bridge spanning an existing railway. There are two abutments (4) of the highway bridge. Characterized in that, Construct a portal pier (6) on the abutment (4), transfer the beam body (2) of the highway bridge to the portal pier (6). The portal pier (6) includes a pile foundation (61) and a cross beam. The rectification method includes the following steps: S1. Construct the pile foundation (61) on both sides of the abutment (4) along the bridge direction. Set a plurality of the pile foundations (61) on both sides of each abutment (4). The detailed steps are as follows: Set four pile foundations (61) on both sides of each abutment. The four pile foundations (61) are divided into two groups. The two pile foundations (61) in the same group are symmetrically located on both sides of the abutment. One group of pile foundations (61) is set on both sides of the abutment close to the existing highway (8), and one group of pile foundations (61) is set on both sides of the abutment far from the existing highway (8); S2. Utilize the railway skylight time to hoist the beam body (2) of the highway bridge onto the existing highway (8) for placement; S3. Demolish the part of the abutment structure with diseases and affecting the safety of the existing railway; S4. Construct the cross beam on the pile foundation (61). The cross beam includes a first cross beam (62) and an ear platform cross beam (63). The first cross beam (62) is placed on the pile foundation (61) far from the existing highway (8), and the ear platform cross beam (63) is placed on the pile foundation (61) close to the existing highway (8). The ear platform cross beam (63) includes a second cross beam, a first ear plate (631), and a second ear plate (632). There are two first ear plates (631). The first ear plate (631) and the second ear plate (632) form a U shape; S5. Utilize the railway skylight time to hoist the precast slab beam (7) and the beam body (2) onto the cross beam. The slab beam (7) is located on the demolished abutment (4); S6. Construct the bridge deck pavement to complete the rectification of the diseased highway bridge.

2. The method for rectifying the diseases of the abutments of a highway bridge spanning an existing railway according to claim 1, Characterized in that, In step S3, when the center of the abutment is a hollow structure, demolishing the part of the abutment with diseases and affecting the safety of the existing railway means demolishing all the abutments above the bottom of the hollow structure of the abutment.

3. The method for rectifying the diseases of the abutments of a highway bridge spanning an existing railway according to claim 1, Characterized in that, The first cross beam (62) is a cuboid and is placed on the tops of two pile foundations (61) symmetrically arranged on the abutment.

4. The method for rectifying the diseases of the abutments of a highway bridge spanning an existing railway according to claim 1, Characterized in that, In step S5, before hoisting the slab beam (7) and the beam body (2), first construct bearings (64) on the cross beam. There are a plurality of the bearings (64), which are arranged on the cross beam at intervals.

5. The method for rectifying the diseases of the abutments of a highway bridge spanning an existing railway according to claim 4, Characterized in that, The bearing (64) is a rubber bearing (64).

6. The method for rectifying the diseases of the abutments of a highway bridge spanning an existing railway according to claim 4, Characterized in that, A stop block (65) is further arranged on the cross beam. A plurality of stop blocks (65) are provided, and the stop blocks (65) are arranged at intervals along the length direction of the highway bridge on both sides of the slab beam (7) or the beam body (2). The top surface of the stop block (65) is higher than the bottom surface of the slab beam (7) or the beam body (2).

7. The method for rectifying the diseases of the abutment of the highway bridge spanning the existing railway according to claim 1, characterized in that, when constructing the bridge deck pavement, it is also necessary to construct auxiliary works and a transition slab (9). The auxiliary works include the bridge deck pavement, expansion joints, sidewalks, railings, and anti-throwing nets. The transition slab (9) is used to connect the slab beam (7) and the existing highway (8).

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