High pier backfilling protection structure for existing urban rail bridge

Abstract

The utility model provides an existing urban rail bridge high pier backfill protection structure which comprises a pile casing body, a pile casing group pile foundation and a pile casing top cover plate, the pile casing group pile foundation comprises a plurality of stand columns annularly arranged around an existing pier, a pile casing bearing platform is arranged at the top ends of the stand columns, the pile casing body is arranged on the pile casing bearing platform, and the pile casing body is arranged on the pile casing bearing platform. The pile casing body is arranged on the outer side of an existing pier in a sleeving mode, a gap is reserved between the inner wall of the pile casing and the outer wall of the existing pier, a backfilling layer is arranged in the gap, and a pile casing top cover plate is arranged at the top end of the pile casing. The backfill pressure and the construction load are dispersed outside the existing bridge structure, it is guaranteed that an original bridge stress system does not change, and under the condition of quality safety and economic reasonability, it is guaranteed that the existing bridge structure is safe and reliable in the whole process.

Description

Technical Field

[0001] The utility model relates to the technical field of rail transportation, in particular to a high pier backfill protection structure of an existing urban rail bridge. Background Art

[0002] As urbanization continues to advance, construction land resources are becoming increasingly scarce, and construction land is no longer limited to flat areas. Urban construction often requires backfilling of areas with large height differences such as valleys and slopes, transforming areas with large height differences into usable construction land. However, as the urban rail transit network continues to increase, existing urban rail bridge structures often exist in valleys, slopes and other areas, and the bridge piers are generally high. The control of deformation of urban rail transit bridges is stricter than that of conventional bridges. If the site is backfilled directly in this area, the soil pressure will act directly on the piers, resulting in increased lateral loads on the piers, excessive lateral deformation, and excessive crack width. If the original bridge is a high-pier continuous rigid frame bridge, the backfill treatment will reduce the actual calculated pier height, increase the pier top stiffness, increase the bending moment, and ultimately increase the negative bending moment at the root of the bridge superstructure, thereby changing the stress state of the entire bridge and affecting the safety of the bridge. Utility Model Content

[0003] In view of this, the problem to be solved by the utility model is to provide a backfill protection structure for the high piers of an existing urban rail bridge, so as to disperse the backfill soil pressure and construction load outside the existing bridge structure, ensure that the original bridge force system does not change, and ensure the safety and reliability of the existing bridge structure throughout the whole process under the conditions of quality safety and economic rationality.

[0004] The utility model solves the above technical problems through the following technical means: The utility model provides a backfill protection structure for high piers of an existing urban rail bridge, comprising a casing body, a casing pile group foundation and a casing top cover plate, wherein the casing pile group foundation is a plurality of columns arranged in a ring around the existing bridge pier, a casing pedestal is arranged at the top of the column, the casing body is arranged on the casing pedestal, the casing body is sleeved on the outside of the existing bridge pier, a gap is left between the inner wall of the casing and the outer wall of the existing bridge pier, a backfill layer is arranged in the gap, and a casing top cover plate is arranged at the top of the casing.

[0005] Furthermore, the backfill layer is arranged as multiple continuous layers, and the height of each backfill layer is not greater than 1.5 meters.

[0006] Furthermore, the pile bottom elevation of the casing pile group foundation is located below the bridge foundation elevation of the existing bridge pier, and the pile top elevation of the casing pile group foundation is located 0.5 to 1 meter above the bridge foundation elevation of the existing bridge pier.

[0007] Furthermore, the gap between the inner wall of the casing body and the outer wall of the existing bridge pier is 0.5-0.8 meters, and the top elevation of the casing body is more than 1 meter higher than the backfill ground.

[0008] Furthermore, the casing top cover is set as a steel plate, the casing body is set as reinforced concrete, the backfill layer is fine sand, and the casing cap and casing pile group foundation are both reinforced concrete structures.

[0009] Furthermore, cement mortar grouting is provided at the joints between the casing top cover plate, the casing body and the existing bridge pier.

[0010] Furthermore, a stone blind ditch for drainage is provided at the bottom of the casing body.

[0011] It can be seen from the above technical scheme that the beneficial effects of the utility model are as follows: the utility model provides a backfill protection structure for high piers of an existing urban rail bridge, including a casing body, a casing pile group foundation and a casing top cover plate, wherein the casing pile group foundation is a plurality of columns arranged in a ring around the existing bridge pier, a casing pedestal is arranged at the top of the column, the casing body is arranged on the casing pedestal, the casing body is sleeved on the outside of the existing bridge pier, a gap is left between the inner wall of the casing and the outer wall of the existing bridge pier, a backfill layer is arranged in the gap, and a casing top cover plate is arranged at the top of the casing. The backfill soil pressure and construction load are dispersed outside the existing bridge structure, ensuring that the original bridge force system does not change, and ensuring the safety and reliability of the existing bridge structure throughout the process under the conditions of quality safety and economic rationality. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the specific implementation of the utility model or the technical solution in the prior art, the following is a brief introduction to the drawings required for the specific implementation or the prior art description. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale.

[0013] Figure 1 A cross-sectional view of the existing high pier backfill protection structure device for urban rail bridges provided by the utility model;

[0014] Figure 2 A top view of the existing high pier backfill protection structure device for urban rail bridges provided by the utility model;

[0015] Figure 3 A cross-sectional view of the casing body of the existing urban rail bridge high pier backfill protection structure device provided by the utility model;

[0016] Reference numerals:

[0017] 1- casing body; 2- casing pile foundation; 3- casing top cover; 4- existing bridge pier; 5- casing cap; 6- backfill layer. DETAILED DESCRIPTION

[0018] The following embodiments of the technical solution of the utility model are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and are therefore only used as examples, and cannot be used to limit the protection scope of the utility model.

[0019] See also Figures 1 to 3 The utility model provides a backfill protection structure for high piers of an existing urban rail bridge, comprising a casing body 1, a casing pile group foundation 2 and a casing top cover plate 3. The casing pile group foundation 2 is a plurality of columns arranged in a ring around an existing bridge pier 4, and a casing pedestal 5 is arranged on the top of the column. The casing body 1 is arranged on the casing pedestal 5, and the casing body 1 is sleeved on the outside of the existing bridge pier 4. A gap is left between the inner wall of the casing and the outer wall of the existing bridge pier 4, and a backfill layer 6 is arranged in the gap. The top of the casing is provided with a casing top cover plate 3. A layer of casing is arranged on the outer wall of the existing bridge pier to protect the existing bridge pier, and a fine sand backfill layer is arranged between the casing body and the existing bridge pier to enhance the protection effect. The backfill soil pressure and construction load are dispersed outside the existing bridge structure, ensuring that the original bridge force system does not change, and ensuring the safety and reliability of the existing bridge structure throughout the process under the conditions of quality safety and economic rationality.

[0020] As a further improvement to the above technical solution, the backfill layer 6 is set as a continuous multi-layer, and the height of each backfill layer 6 is not more than 1.5 meters. The backfill layer 6 is set as a multi-layer with a height of 1.5 meters per layer, and each layer is backfilled separately and compacted during the backfilling process.

[0021] As a further improvement to the above technical solution, the pile bottom elevation of the casing pile group foundation 2 is located below the bridge foundation elevation of the existing bridge pier 4, and the pile top elevation of the casing pile group foundation 2 is located 0.5-1 meter above the bridge foundation elevation of the existing bridge pier 4. The casing pile group foundation 2 is set outside the bridge foundation of the existing bridge pier 4, and rotary piles or manually dug pile holes are selected, and the pile bottom elevation of the column of the pile group is located below the existing bridge foundation elevation, and the pile top elevation is located about 0.5-1.0 meter above the existing bridge foundation elevation cap or the current ground elevation.

[0022] As a further improvement to the above technical solution, the gap between the inner wall of the casing body 1 and the outer wall of the existing bridge pier 4 is 0.5-0.8 meters, and the top elevation of the casing body 1 is more than 1 meter higher than the backfill ground. The casing body 1 is set to a tube structure similar to the existing bridge pier 4, and the gap between the inner wall of each side of the casing body 1 and the corresponding outer wall of the existing bridge pier 4 is the same, and the gap is 0.5-0.8 meters to provide appropriate strength; the height of the casing is set 1 meter higher than the backfill ground elevation, so that it can completely cover the backfill part and completely protect the bridge pier.

[0023] As a further improvement to the above technical solution, the casing top cover plate 3 is set as a steel plate, the casing body 1 is set as reinforced concrete, the backfill layer 6 is fine sand, and the casing cap 5 and the casing pile group foundation 2 are both reinforced concrete structures. Cement mortar joints are set at the joints between the casing top cover plate 3 and the casing body 1 and the existing bridge pier 4. A steel plate cover plate is set on the top plate of the casing body 1, and cement mortar joints are set at the connection between the steel plate cover plate and the bridge pier and the casing body 1 to completely close the casing body 1, so as to prevent rainwater from entering the casing body 1.

[0024] As a further improvement of the above technical solution, a stone blind ditch for drainage is provided at the bottom of the casing body 1. A stone blind ditch is laid at the bottom of the casing body 1 in conjunction with the road flat field for drainage to prevent water accumulation at the bottom of the casing.

[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the utility model, and they should all be included in the scope of the claims and specification of the utility model.

Claims

1. A high pier backfill protection structure for an existing urban rail bridge, characterized in that: The invention comprises a casing body (1), a casing pile group foundation (2) and a casing top cover plate (3), wherein the casing pile group foundation (2) is a plurality of columns arranged in a ring around an existing bridge pier (4), a casing base (5) is arranged at the top of each column, the casing body (1) is arranged on the casing base (5), the casing body (1) is sleeved on the outside of the existing bridge pier (4), a gap is left between the inner wall of the casing and the outer wall of the existing bridge pier (4), a backfill layer (6) is arranged in the gap, and a casing top cover plate (3) is arranged at the top of the casing.

2. The existing high pier backfill protection structure of urban rail bridge according to claim 1 is characterized by: The backfill layer (6) is arranged as multiple continuous layers, and the height of each backfill layer (6) is no greater than 1.5 metres.

3. The existing high pier backfill protection structure of urban rail bridge according to claim 2 is characterized by: The pile bottom elevation of the casing pile group foundation (2) is located below the bridge foundation elevation of the existing bridge pier (4), and the pile top elevation of the casing pile group foundation (2) is located 0.5 to 1 meter above the bridge foundation elevation of the existing bridge pier (4).

4. The existing high pier backfill protection structure of urban rail bridge according to claim 3 is characterized by: The gap between the inner wall of the casing body (1) and the outer wall of the existing bridge pier (4) is 0.5-0.8 meters, and the top elevation of the casing body (1) is more than 1 meter higher than the backfill ground.

5. The existing high pier backfill protection structure of urban rail bridge according to claim 4 is characterized by: The casing top cover plate (3) is configured as a steel plate, the casing body (1) is configured as reinforced concrete, the backfill layer (6) is fine sand, and the casing cap (5) and the casing pile group foundation (2) are both reinforced concrete structures.

6. The existing high pier backfill protection structure of urban rail bridge according to claim 1 is characterized by: Cement mortar grouting is provided at the joints between the casing top cover plate (3), the casing body (1) and the existing bridge pier (4).

7. The existing high pier backfill protection structure of urban rail bridge according to claim 1 is characterized by: A stone blind ditch for drainage is provided at the bottom of the casing body (1).

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