A construction method for newly building the lower structure of a bridge at an existing underground culvert

Abstract

The present invention discloses a construction method for building a new bridge substructure at an existing underground culvert, comprising the following steps: S1: setting a long casing in a drilled pile foundation hole, and injecting concrete into the long casing to form a pile foundation; S2: constructing a box culvert of the drilled existing underground culvert, and setting a waterproof structure and a water pipe penetrating the waterproof structure; S3: constructing a cap on the pile foundation; S4: constructing piers on the cap, and building a new underground culvert on the other side of the cap. The construction of the pile foundation is achieved by setting a long casing, thereby preventing the mud in the long casing from leaking out and polluting the environment, and also preventing the water in the existing underground culvert from flowing into the casing to dilute the mud and cause a collapse; in addition, a waterproof structure and a water pipe penetrating the waterproof structure are set in the box culvert to prevent the water in the box culvert from flowing into the pile foundation, while ensuring normal drainage in the existing box culvert, solving the municipal drainage problem after the existing underground culvert is demolished and before the new culvert is built.

Description

Technical Field

[0001] The present invention relates to the technical field of municipal construction, and in particular to a construction method for building a new bridge substructure at an existing underground culvert. Background Art

[0002] In recent years, with the continuous growth of urban populations, traffic demand has continued to increase. New urban elevated bridges and additional lanes can significantly alleviate urban traffic pressure. During urban bridge construction, due to conflicts between the new bridge substructure and existing underground culverts (including but not limited to drainage and gas), the design incorporates a new underground drainage culvert. Only after the new culvert is completed and operational can the existing culvert be removed before bridge construction can proceed. However, in actual construction, due to geological and hydrological conditions, and complex underground pipelines, the progress of the new culvert is slow. If the existing culvert is removed after the new culvert is operational, the construction schedule cannot be guaranteed. If the existing culvert is removed first, construction and flood season drainage cannot be guaranteed, which can easily cause significant social impacts. Summary of the Invention

[0003] In view of the above-mentioned defects of the existing technology, a construction method for building a new bridge substructure at the existing underground culvert is provided, which solves the municipal drainage problem after the existing underground culvert is demolished and before the new culvert is built.

[0004] The technical solution adopted by the present invention to solve the above technical problems is:

[0005] A construction method for constructing a new bridge substructure at an existing underground culvert, characterized by comprising the following steps:

[0006] S1: A long casing is set in the drilled pile foundation hole, and concrete is poured into the long casing to form the pile foundation;

[0007] S2: Treat the box culvert of the existing underground pipe culvert that has been drilled, and install a waterproof structure and a water pipe that penetrates the waterproof structure inside the box culvert;

[0008] S3: Carry out foundation cap construction on pile foundation;

[0009] S4: Pier construction is carried out on the cap and a new underground culvert is built on the other side of the cap.

[0010] According to the above technical solution, if the new rainwater pipeline is close to the existing gas pipeline, add the following steps between S3 and S4 or after S4:

[0011] A: Move the new rainwater pipe to the existing box culvert for construction.

[0012] According to the above technical solution, in step S1, a rotary drilling rig is used to drill along the ground according to the design drawings, and the drilling is carried out to 0.5~1m below the bottom elevation of the box culvert of the existing underground pipe culvert, and the bottom of the long casing is located 0.5~1m below the bottom plate of the box culvert.

[0013] According to the above technical solution, the long casing is welded by multiple sections of standard casing with the same size. The welds between two adjacent casings should be dense and full, and there should be no leaks.

[0014] According to the above technical solution, the waterproof structure includes clay bags and clay ton bags. The clay bags are arranged around the long casing and located in the box culvert. The clay ton bags are arranged upstream and downstream of the underground culvert, and the long casing is located between the upstream and downstream clay ton bags. The water pipe passes through the clay ton bags to connect the upstream and downstream underground culverts.

[0015] According to the above technical solution, step S2 includes:

[0016] S21: Remove the road and soil layer above the existing underground culvert of the excavated piles, and lift the top plate of the existing underground culvert near the pile foundation:

[0017] S22: Setting clay bags around the long casing;

[0018] S23: Clay ton bags upstream and downstream of the existing underground culvert;

[0019] S24: A water pipe penetrating the waterproof structure is provided in the waterproof structure in the existing underground culvert.

[0020] According to the above technical solution, before stacking clay bags around the long casing, a layer of colored strips of cloth is first laid along the bottom plate of the box culvert and around the long casing to separate the existing box culvert from the long casing.

[0021] According to the above technical solution, in step S3, the water between the clay bags at both ends is drained out, and then the foundation support and construction are carried out.

[0022] According to the above technical solution, in step S4, before the pier construction, the excavated soil of the foundation is backfilled between the clay bags at both ends, and then the pier tie beam support frame and the pier work frame are erected to carry out the pier construction.

[0023] According to the above technical solution, the newly built rainwater pipe located in the existing underground culvert is encapsulated with concrete, and other parts of the existing underground culvert are backfilled with aggregate sand and gravel mixture.

[0024] The present invention has the following beneficial effects:

[0025] 1. The construction of pile foundation is realized by setting up long casing to prevent the mud in the long casing from leaking out and polluting the environment. At the same time, it also prevents the water in the existing underground culvert from flowing into the casing to dilute the mud and cause collapse. In addition, a waterproof structure and a water pipe running through the waterproof structure are set up in the box culvert to prevent the water in the box culvert from flowing into the pile foundation. At the same time, the normal drainage of the existing box culvert is guaranteed, solving the municipal drainage problem after the existing underground culvert is broken and before the new culvert is built.

[0026] 2. By setting up clay ton bags upstream and downstream of the new foundation in the existing underground culvert, dry working conditions are created for the foundation construction. By setting up temporary water pipes between the clay ton bags on both sides, the drainage needs during construction and flood season are guaranteed.

[0027] 3. Because the new rainwater pipe is close to the existing gas pipeline, any support and excavation work on the rainwater pipe would inevitably have a significant impact on the gas pipeline, posing a significant safety hazard. Relocating the new rainwater pipe to the existing box culvert reduces the cost of support and excavation during the construction of the new rainwater pipe, while also avoiding the safety hazards of construction near the existing gas pipeline.

[0028] 4. Temporary backfilling of soil in the existing underground culvert creates conditions for pier construction. At the same time, the design of the water pipe also ensures drainage needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is the original site section and newly constructed structure drawing of the embodiment provided by the present invention;

[0030] Figure 2 This is a cross-sectional view during enclosure construction according to an embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of the locations of the new bridge substructure and the existing underground culvert according to an embodiment of the present invention;

[0032] Figure 4 This is a schematic diagram of the upper pile foundation drilling and long casing installation of an existing underground culvert according to an embodiment of the present invention;

[0033] Figure 5 Schematic diagram of the box culvert excavation and arrangement of clay bags around the long casing according to an embodiment of the present invention;

[0034] Figure 6 The present invention provides embodiment 1-1;

[0035] Figure 7 This is a cross-sectional view of the foundation pile construction according to an embodiment of the present invention;

[0036] Figure 8 This is a plan view of the foundation construction of an embodiment of the present invention;

[0037] Figure 9 This is a cross-sectional view of the pier construction according to an embodiment of the present invention;

[0038] Figure 10 This is a construction drawing of the embodiment of the present invention for migrating the rainwater pipe into the existing box culvert;

[0039] Figure 11 It is a cross-sectional view of an existing underground pipe culvert according to an embodiment of the present invention;

[0040] Figure 12 It is a flow chart of an embodiment of the present invention;

[0041] In the figure, 1. New underground culvert; 2. Capping platform; 3. Pile foundation; 4. Existing underground culvert; 5. Long casing; 6. Clay bag; 7. Soil layer; 8. Existing underground culvert side plate; 9. Existing underground culvert top plate; 10. Existing underground culvert bottom plate; 11. Steel sheet pile; 12. Water pipe; 13. Clay ton bag; 14. Pier; 15. Pier tie beam support frame; 16. Pier work frame; 17. Backfill; 19. Gas pipeline; 20. New rainwater pipeline; 21. Concrete; 22. Sand and gravel mixture. DETAILED DESCRIPTION

[0042] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0043] Reference Figures 1 to 12 As shown, the pile foundation and pier cap of the new bridge project conflict with the existing box culvert to the south (taking the embodiment shown in the figure as an example, the pile foundation extends 100mm into the inner edge of the box culvert side wall, and the pier cap extends 600mm into the inner edge of the box culvert side wall; the existing underground culvert top plate 9 is a 300mm thick precast reinforced concrete cover plate, the existing underground culvert side plates 8 on both sides are 500mm thick brick walls, and the existing underground culvert bottom plate 10 is a 300mm thick reinforced concrete slab, resulting in a net size of 2.8m*1.8m inside the box culvert). During the drilling process for the pile foundation, drilling is performed directly from the ground to penetrate the box culvert side wall.

[0044] The present invention provides a construction method for constructing a new bridge substructure at an existing underground culvert, comprising the following steps:

[0045] S1: A long casing 5 is installed in the drilled pile foundation hole, and concrete is poured into the long casing to form a pile foundation 3;

[0046] S2: Treat the box culvert of the existing underground pipe culvert 4 that has been drilled, and install a waterproof structure and a water pipe penetrating the waterproof structure in the box culvert;

[0047] S3: Construction of cap 2 on the pile foundation;

[0048] S4: Pier 14 is constructed on the cap and a new underground culvert 1 is built on the other side of the cap.

[0049] This embodiment realizes the construction of pile foundation by setting up long casing, preventing the mud in the long casing from leaking out and polluting the environment, and also preventing the water in the existing underground culvert from flowing into the casing to dilute the mud and cause collapse. In addition, a waterproof structure and a water pipe passing through the waterproof structure are set up in the box culvert to prevent the water in the box culvert from flowing into the pile foundation, while ensuring the normal drainage of the existing box culvert, solving the municipal drainage problem after the existing underground culvert is broken and before the new culvert is built.

[0050] Furthermore, if the new stormwater pipe 20 is located close to the existing gas pipeline 18, then add the following step between S3 and S4, or after S4: A: Relocate the new stormwater pipe to the existing box culvert for construction. Because the new stormwater pipe is located close to the existing gas pipeline, supporting and excavating the new stormwater pipe would significantly impact the gas pipeline, posing a significant safety hazard. Relocating the new stormwater pipe to the existing box culvert reduces the costs of supporting and excavating the new stormwater pipe, while also avoiding the safety hazards of construction near the existing gas pipeline.

[0051] Furthermore, in step S1, a rotary drilling rig is used to drill along the ground according to the design drawings, and the drilling is carried out to 0.5 to 1 m below the bottom elevation of the box culvert of the existing underground pipe culvert, and the bottom of the long casing is located 0.5 to 1 m below the bottom plate of the box culvert.

[0052] Furthermore, the long casing is welded together from multiple sections of standard casing of the same size. The welds between two adjacent casings should be dense and full, without any leaks. This prevents the mud inside the long casing from leaking out and polluting the environment. It also prevents water from existing underground culverts from flowing into the long casing and diluting the mud, causing collapse.

[0053] Furthermore, the waterproof structure includes clay bags 6 and clay bulk bags 13. The clay bags are placed around the long casing and located within the box culvert. The clay bulk bags are stacked upstream and downstream of the underground culvert, with the long casing located between the upstream and downstream clay bulk bags. A water pipe passes through the clay bulk bags to connect the upstream and downstream underground culverts. The length of the water pipe exceeds the distance between the clay bulk bags on both sides, ensuring drainage requirements during the foundation construction.

[0054] Further, step S2 includes:

[0055] S21: Remove the road and soil layer 7 above the existing underground culvert of the excavated pile, and lift the top plate of the existing underground culvert near the pile foundation:

[0056] S22: Setting clay bags around the long casing;

[0057] S23: Clay ton bags upstream and downstream of the existing underground culvert;

[0058] S24: A water pipe 12 is provided in the waterproof structure in the existing underground culvert and penetrates the waterproof structure.

[0059] Furthermore, before stacking clay bags around the long casing, a layer of colored strips of cloth is laid along the bottom plate of the box culvert and around the long casing to separate the existing box culvert from the long casing, thereby ensuring the quality of pile foundation construction and ensuring normal drainage.

[0060] Furthermore, in step S3, the water between the clay bags at both ends is drained to create dry working conditions for the foundation cap construction, and then the foundation cap support and construction are carried out. Steel sheet piles 11 are set on both sides of the foundation cap for support, and the steel sheet piles are pulled out after the foundation cap construction is completed.

[0061] Furthermore, in step S4, before pier construction begins, the excavated soil from the foundation is backfilled between the clay bags at both ends (see backfill 17 in the figure). Pier tie beam support frames 15 and pier work frames 16 are then erected for pier construction. Temporary backfill within the existing underground culvert creates conditions for pier construction, while the design of the water pipe also ensures drainage requirements.

[0062] Furthermore, the new rainwater pipe located in the existing underground culvert is encapsulated with concrete 21, and the rest of the existing underground culvert is backfilled with aggregated sand and gravel mixture 22. During the construction of relocating the new rainwater pipe to the existing box culvert, the water pipe is removed and the new rainwater pipe is constructed.

[0063] The above are only preferred embodiments of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention still fall within the scope of protection of the present invention.

Claims

1. A construction method for constructing a new bridge substructure at an existing underground culvert, characterized by: The steps include: S1: A long casing is set in the drilled pile foundation hole, and concrete is poured into the long casing to form the pile foundation; S2: Treat the box culvert of the existing underground pipe culvert that has been drilled, and install a waterproof structure and a water pipe that penetrates the waterproof structure inside the box culvert; The waterproof structure includes clay bags and clay ton bags. The clay bags are placed around the long casing and inside the box culvert. The clay ton bags are placed upstream and downstream of the underground culvert, and the long casing is located between the upstream and downstream clay ton bags. The water pipe passes through the clay ton bags to connect the upstream and downstream underground culverts. S3: Carry out foundation cap construction on pile foundation; S4: Pier construction is carried out on the cap and a new underground culvert is built on the other side of the cap; If the new rainwater pipe is close to the existing gas pipe, add the following steps between S3 and S4 or after S4: A: Move the new rainwater pipe to the existing box culvert for construction.

2. The construction method for constructing a new bridge substructure at an existing underground culvert according to claim 1, characterized in that: In step S1, a rotary drilling rig is used to drill along the ground according to the design drawings, and the drilling is carried out to 0.5-1 m below the bottom elevation of the box culvert of the existing underground pipe culvert, and the bottom of the long casing is located 0.5-1 m below the bottom plate of the box culvert.

3. The construction method for constructing a new bridge substructure at an existing underground culvert according to claim 2, characterized in that: The long casing is welded by multiple sections of standard casing with the same size. The welds between two adjacent casings should be dense and full without any leaks.

4. The construction method for constructing a new bridge substructure at an existing underground culvert according to claim 1, characterized in that: Step S2 includes: S21: Remove the road and soil layer above the existing underground culvert of the excavated piles, and lift the top plate of the existing underground culvert near the pile foundation: S22: Setting clay bags around the long casing; S23: Clay ton bags upstream and downstream of the existing underground culvert; S24: A water pipe penetrating the waterproof structure is provided in the waterproof structure in the existing underground culvert.

5. The construction method for constructing a new bridge substructure at an existing underground culvert according to claim 4, characterized in that: Before stacking clay bags around the long casing, a layer of colored strips of cloth is laid along the bottom plate of the box culvert and around the long casing to separate the existing box culvert from the long casing.

6. The construction method for constructing a new bridge substructure at an existing underground culvert according to claim 4, characterized in that: In step S3, the water between the clay bags at both ends is drained out, and then the foundation support and construction are carried out.

7. The construction method for constructing a new bridge substructure at an existing underground culvert according to claim 4, characterized in that: In step S4, before the pier construction, the excavated soil of the foundation is backfilled between the clay bags at both ends, and then the pier tie beam support frame and the pier work frame are erected to carry out the pier construction.

8. The construction method for constructing a new bridge substructure at an existing underground culvert according to claim 1, characterized in that: The newly built rainwater pipe located in the existing underground culvert is encapsulated with concrete, and other parts of the existing underground culvert are backfilled with aggregate sand and gravel mixture.

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