Method for building bridge piers in middle isolation strip of existing lines of busy expressway

Abstract

The invention discloses a method for building piers in a middle isolation belt of existing lines of a busy expressway, and relates to a pier manufacturing process. Comprising the following steps: measuring the floor contour of piers; building a fence outside the floor contour; excavating an inclined pit outside an expressway; excavating a tunnel from the bottom of the inclined pit to the center position of the fence, upwards excavating a foundation pit in the tunnel located below the fence, excavating pile pits in the positions of the floor contours of the two piers at the bottom of the foundation pit, and erecting template brackets at the pile pits. Pouring the reinforcement cage outside the expressway by using a concrete pump truck, forming a concrete pile after the reinforcement cage is poured, maintaining, removing the mold, backfilling the foundation pit, backfilling the tunnel, and backfilling the tunnel. The tunnel capable of penetrating through the isolation belt needing to build the bridge pier is excavated outside the lane of the expressway, materials needing to build the bridge pier are transported along the tunnel, and the defects that when the bridge pier is built on the isolation belt, the normal driving lane of the expressway is blocked, and driving safety is endangered are overcome.

Description

Technical Field

[0001] This invention relates to a bridge pier manufacturing process, and more particularly to a method for constructing bridge piers in the median strip of a busy existing highway. Background Technology

[0002] Based on the needs of transportation development, it is necessary to replan and construct highways and bridges on the existing road network. Since highways and railways are generally continuous, when encountering existing ordinary highways, new highways can be merged or intersected with them. When encountering railways or expressways, new ordinary highways can only choose to pass under or over expressways. When choosing to build a bridge over an expressway, multiple piers need to be constructed at intervals to support the overpass. Due to the large overall width of expressways, it is necessary to use the median strip of the expressway to build piers for the bridge over the expressway. The pier is mainly composed of a cap and a pier body. The function of the cap is to distribute and evenly transmit the large and concentrated force from the bridge span support to the pier body and abutment. The pier is generally a solid structure made of concrete or stone masonry, with a pier cap on the pier body, which connects to the foundation.

[0003] The traditional method for constructing bridge piers across the median strip of a highway typically involves enclosing the median strip where the piers will be built and constructing the bridge within the enclosure. The median strip is generally 2.5-3 meters wide, while the bridge piers are typically 1.2 meters wide. After construction, the impact on the highway is minimal. However, because building bridge piers requires excavating pile holes and subsequently inserting steel cages and pouring concrete, it necessitates the assistance of engineering vehicles and a large number of personnel. Therefore, the lateral width of the median strip enclosure at the pier construction site is generally 10 meters. Since two piers need to be built side-by-side, the length must reach over 10 meters. Such a large enclosure inevitably encroaches on the normal highway road surface, causing a sudden narrowing of the highway at the enclosure location. On busy trunk highways, this can easily lead to traffic congestion due to the sudden narrowing of the road. Furthermore, the need for construction workers to frequently enter and exit the enclosure poses a significant safety hazard. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention discloses a method for constructing bridge piers in the median strip of a busy existing highway. By excavating a tunnel outside the highway lanes that can connect to the median strip where the bridge piers need to be constructed, the materials for constructing the bridge piers can be transported along the tunnel. This method overcomes the drawbacks of occupying the normal driving lanes of the highway when constructing bridge piers in the median strip between the two lanes of the highway, which causes congestion of the normal driving lanes and endangers driving safety.

[0005] To achieve the aforementioned objective, the present invention employs the following technical solution: A method for constructing bridge piers in the median strip of an existing busy highway includes the following steps: Step 1: Measure the footprint of the bridge piers: Measure the footprint of the two bridge piers that need to be built at intervals within the median strip between two highway lanes that are spaced apart and have opposite directions of travel. Step 2: Construct a fence outside the land area outline: Erect a fence at the outer edge of the area formed by the two bridge piers located at intervals within the isolation zone; Step 3: Excavate a sloping pit outside the highway: Excavate a sloping pit at the corresponding position outside one of the highway lanes and in the middle of the fence, and provide side wall support. Step 4: Excavate a tunnel from the bottom of the sloping pit towards the center of the enclosure: Excavate a tunnel horizontally from the bottom of the sloping pit towards the soil layer below the center of the enclosure and ensure proper sidewall support. Step 5: Excavate the foundation pit upwards at the end of the tunnel located directly below the center of the enclosure: Excavate the inclined tunnel upwards at the end of the tunnel until the exit inside the enclosure is dug out and support it in time. At the exit inside the enclosure, gradually excavate the foundation pit that is level with the bottom of the tunnel and slightly smaller than the enclosure on the outer edge and do a good job of side wall support. Step 6: Excavate pile pits at the bottom of the foundation pit where the two bridge piers occupy the land outline: Manually excavate pile pits of the required depth at the bottom of the foundation pit located below the land outline of the two bridge piers and provide side wall support. Step 7: Erect formwork supports at the opening of the pile pits: Erect formwork supports at the openings of the two pile pits to the required height. Step 8: Place the steel reinforcement cages into the formwork support: Make two steel reinforcement cages of the required length, temporarily close one side of the highway lane, use a crane to lift the two steel reinforcement cages and place them into the two sets of formwork support along the top of the two sets of formwork support. After placement, open the closed side of the highway lane. Step 9: Use a concrete pump truck to pour concrete into the steel cage outside the highway: Drive the concrete pump truck to the outside of one side of the highway lane, move the pump head to the top of the steel cage, and pour concrete into the top of the steel cage until the formwork support is filled. Step 10: After the steel reinforcement cage is poured, it forms a concrete pile and is cured: After the two steel reinforcement cages that have been poured with concrete are dried and cured, they form two concrete bridge piers. Step 11, Demolding: Remove the formwork supports surrounding the two concrete piers; Step 12: Backfill the foundation pit: Backfill the foundation pit manually, so that the backfill soil covers the parts of the two concrete bridge piers located in the foundation pit. Step 13: Backfill the tunnel: Backfill the tunnel and the sloping pit with backfill soil manually; Step Fourteen: Remove and restore the enclosure: After the backfill soil has been basically completed in the foundation pit, tunnel and inclined pit, remove the enclosure erected in the isolation zone and restore the original greenery after leveling the foundation pit.

[0006] The method for constructing bridge piers in the median strip of a busy existing highway, in step one, each bridge pier has a footprint with a length of 2 meters and a width of 1.2 meters, and the distance between the footprints of two bridge piers is 5.6 meters.

[0007] In the method for constructing bridge piers in the median strip of a busy existing highway, step two involves enclosing an area with a length of 12 meters, a width of 2.6 meters, and a height of 2.5 meters.

[0008] In the method for constructing bridge piers in the median strip of a busy existing highway, step three involves using a laser rangefinder to define the location of the sloping pit. The depth of the sloping pit is 5 meters, the width is 2 meters, and the slope is 20 degrees.

[0009] The method for constructing bridge piers in the median strip of a busy existing highway, step four involves excavating a tunnel using the shallow buried tunneling method, with the tunnel being 2.2 meters high and 2 meters wide.

[0010] In the method for constructing bridge piers in the median strip of a busy existing highway, step five involves a foundation pit with a depth of 5 meters, a length of 11 meters, and a width of 2.4 meters.

[0011] In the method for constructing bridge piers in the median strip of a busy existing highway, the depth of the two pile pits in step six is ​​5 meters.

[0012] In the method for constructing bridge piers in the median strip of a busy existing highway, step seven involves a formwork support with a height of 15 meters and connection and installation holes on the side wall of the formwork support, 5 meters from the bottom of the formwork support.

[0013] In the method for constructing bridge piers in the median strip of a busy existing highway, each steel cage is divided into two parts, each 10 meters long, in step eight. The bottom of the straight steel bars in the upper half of the steel cage is provided with external thread A, and the top of the straight steel bars in the lower half of the steel cage is provided with external thread B. The external threads A and B are in opposite directions. First, the lower half of the steel cage is hoisted into place along the top of the formwork support, and then the upper half of the steel cage is hoisted into place along the top of the formwork support. The two halves of the steel cage are connected by connecting sleeves with oppositely oriented screw holes at both ends at the connection and installation hole. After the two halves of the steel cage are connected, the connection and installation hole is sealed.

[0014] The method for constructing bridge piers in the median strip of a busy existing highway, in steps twelve to fourteen, involves backfilling the foundation pit by first filling it with backfill soil to form two opposite slopes, with the top of the slopes located outside the foundation pit and supported by the inner edge of the enclosure. Then, the tunnel and the sloping pit are backfilled. Subsequently, the excess backfill soil located outside the foundation pit is filled into the foundation pit in layers.

[0015] Due to the adoption of the above technical solution, the present invention has the following beneficial effects: The method for constructing bridge piers in the median strip of a busy existing highway, as described in this invention, overcomes the drawbacks of constructing bridge piers in the median strip between two lanes of a highway, which requires occupying the normal driving lanes, causing traffic congestion and endangering driving safety. This invention is unique, easy to operate, and highly safe, effectively improving construction efficiency, minimizing personal and property safety risks, ensuring normal highway traffic, and avoiding large-scale congestion on busy highways. It has high market promotion value. Attached Figure Description

[0016] Figure 1 This is a flowchart of the construction steps of the present invention; Figure 2 This is a structural schematic diagram of the first construction step of the present invention; Figure 3 This is a structural schematic diagram of the second construction step of the present invention; Figure 4 This is a structural schematic diagram of the third construction step of the present invention; Figure 5 This is a cross-sectional view of the third construction step of the present invention; Figure 6 This is a structural schematic diagram of the fourth construction step of the present invention; Figure 7 This is a cross-sectional view of the fourth construction step of the present invention; Figure 8 This is a structural schematic diagram of step five of the construction process of the present invention; Figure 9 This is a cross-sectional view of step five of the construction process of this invention; Figure 10 This is a structural schematic diagram of construction step six of the present invention; Figure 11 This is a cross-sectional view of step six of the construction process of this invention; Figure 12 This is a structural schematic diagram of construction step seven of the present invention; Figure 13 This is a cross-sectional view of construction step seven of the present invention; Figure 14This is a structural schematic diagram of construction step eight of the present invention; Figure 15 This is a structural schematic diagram of construction step nine of the present invention; Figure 16 This is a structural schematic diagram of construction step ten of the present invention; Figure 17 This is a structural schematic diagram of construction step eleven of the present invention; Figure 18 This is a structural schematic diagram of construction step twelve of the present invention; Figure 19 This is a cross-sectional view of construction step twelve of the present invention; Figure 20 This is a structural schematic diagram of construction step thirteen of the present invention; Figure 21 This is a structural schematic diagram of construction step fourteen of the present invention.

[0017] In the diagram: 1. Highway lane; 2. Bridge pier footprint outline; 3. Median strip; 4. Fence; 5. Inclined pit; 6. Tunnel; 7. Foundation pit; 8. Pile pit; 9. Formwork support; 10. Reinforcing cage; 11. Concrete pump truck; 12. Concrete bridge pier; 13. Backfill soil. Detailed Implementation

[0018] The present invention can be explained in more detail through the following embodiments. The present invention is not limited to the following embodiments. The purpose of disclosing the present invention is to protect all changes and modifications within the scope of the present invention. Combined with appendix Figures 1-21 The method for constructing bridge piers in the median strip of a busy existing highway includes the following steps: Step 1: Measure the footprint outline of the bridge piers: Measure the footprint outline 2 of the two bridge piers to be built at intervals within the median strip 3 between two highway lanes 1 that are spaced apart and have opposite directions of travel. The length of each bridge pier footprint outline 2 is 2 meters and the width is 1.2 meters. The distance between the two bridge pier footprint outlines 2 is 5.6 meters. Step 2: Construct a fence outside the land area outline: erect a fence 4 at the outer edge of the area formed by the two bridge piers located at intervals within the isolation zone 3. The fence 4 encloses an area with a length of 12 meters, a width of 2.6 meters, and a height of 2.5 meters. Step 3: Excavate a sloping pit outside the highway: Excavate a sloping pit 5 at the corresponding position outside lane 1 of one of the highways and the middle of the fence 4, and do a good job of side wall support. Use a laser rangefinder to limit the excavation position of the sloping pit 5. The depth of the bottom of the sloping pit 5 is 5 meters, the width is 2 meters, and the slope of the sloping pit 5 is 20 degrees. Step 4: Excavate a tunnel from the bottom of the sloping pit to the center of the enclosure: At the bottom of the sloping pit 5, excavate tunnel 6 horizontally into the soil layer below the middle of the enclosure 4 and provide side wall support. The method for excavating tunnel 6 is shallow buried tunneling. The height of tunnel 6 is 2.2 meters and the width is 2 meters. Step 5: Excavate the foundation pit upwards at the end of the tunnel located directly below the center of the enclosure: Excavate the inclined passage upwards at the end of the tunnel 6 until the exit inside the enclosure 4 is dug out and support it in time. At the exit inside the enclosure 4, gradually excavate the foundation pit 7, which is level with the bottom of the tunnel 6 and slightly smaller than the outer edge of the enclosure 4, and do a good job of side wall support. The depth of the foundation pit 7 is 5 meters, the length is 11 meters and the width is 2.4 meters. Step 6: Excavate pile pits at the bottom of the foundation pit where the two bridge piers occupy the land outline: At the bottom of the foundation pit 7 located below the land outline 2 of the two bridge piers, manually excavate pile pits 8 to the required depth and provide side wall support. The depth of the two pile pits 8 is 5 meters. Step 7: Erect formwork supports at the opening of the pile pits: Erect formwork supports 9 at the openings of the two pile pits 8 to the required height. The height of the formwork supports 9 is 15 meters. Connection and installation holes are provided on the side wall of the formwork supports 9 5 meters away from the bottom of the formwork supports 9. Step 8: Place the steel cages into the formwork support: Make two steel cages 10 of the required length, temporarily close one side of the highway lane 1, use a crane to lift the two steel cages 10 and place them into the two sets of formwork supports 9 from the top. After placement, open the closed side of the highway lane 1. Each steel cage 10 is divided into two parts, each 10 meters long. The bottom of the straight steel bars of each upper half of the steel cage is provided with external thread A, and the top of the straight steel bars of each lower half of the steel cage is provided with external thread B. The external threads A and B are opposite in direction. First, lift the lower half of the steel cage into the formwork support 9 from the top, and then lift the upper half of the steel cage into the formwork support 9 from the top. The two halves of the steel cage are connected by connecting sleeves with opposite screw holes at both ends at the connection installation hole. After the two halves of the steel cage are connected, close the connection installation hole. Step 9: Use a concrete pump truck to pour concrete into the steel cage outside the highway: Drive the concrete pump truck 11 to the outside of one side of the highway lane 1, move the pump head to the top of the steel cage 10, and pour concrete into the top of the steel cage 10 until the formwork support 9 is filled. Step 10: After the steel reinforcement cage is poured, it forms a concrete pile and is cured: After the two steel reinforcement cages 10 that have been poured with concrete are dried and cured, they form two concrete piers 12. Step 11, Demolding: Remove the formwork supports 9 surrounding the two concrete piers 12; Step 12: Backfill the foundation pit: Backfill the foundation pit 7 with soil 13 manually, so that the backfill soil 13 covers the parts of the two concrete piers 12 located in the foundation pit 7. Step 13: Backfill the tunnel: Use manual labor to backfill the tunnel 6 and the inclined pit 5 with backfill soil 13; Step 14: Remove the fence and restore: After the backfill soil 13 has been used to backfill the foundation pit 7, tunnel 6 and inclined pit 5, remove the fence 4 erected in the isolation zone 3 and level the foundation pit 7 and restore the original greenery. In steps twelve to fourteen, the backfilling method for foundation pit 7 is as follows: first, backfill soil 13 is used to fill foundation pit 7 into two oppositely set slopes, so that the top of the slope is located outside foundation pit 7 and relies on the inner edge of enclosure 4 for support. Then, tunnel 6 and sloping pit 5 are backfilled. Subsequently, the excess backfill soil 13 located outside foundation pit 7 is filled into foundation pit 7 in layers. This application overcomes the drawbacks of constructing bridge piers on highways by excavating tunnels outside the highway lanes to connect the median strip where bridge piers need to be built, and transporting the materials needed for the bridge piers along the tunnels. This overcomes the drawbacks of occupying the normal driving lanes of the highway when constructing bridge piers in the median strip between two-way lanes, which causes traffic congestion and endangers driving safety.

[0019] The parts of this invention not described in detail are prior art.

Claims

1. A method for constructing bridge piers in the median strip of an existing busy highway, characterized by: Includes the following steps: Step 1: Measure the footprint of the bridge piers: Measure the footprint of the two bridge piers that need to be built at intervals within the median strip (3) set between two highway lanes (1) that are spaced apart and have opposite directions of travel (2). Step 2: Construct a fence outside the land area outline: erect a fence (4) at the outer edge of the area formed by the land area outline (2) of the two bridge piers located in the isolation zone (3). Step 3: Excavate a sloping pit outside the highway: Excavate a sloping pit (5) at the corresponding position outside one of the highway lanes (1) and in the middle of the fence (4) and provide side wall support; Step 4: Excavate a tunnel from the bottom of the sloping pit to the center of the enclosure: Excavate a tunnel (6) horizontally from the bottom of the sloping pit (5) to the soil layer below the center of the enclosure (4) and provide side wall support. Step 5: Excavate the foundation pit upward at the end of the tunnel located directly below the center of the enclosure: Excavate the inclined passage upward at the end of the tunnel (6) until the exit inside the enclosure (4) is dug out and supported in time. At the exit inside the enclosure (4), gradually excavate the foundation pit (7) that is level with the bottom of the tunnel (6) and slightly smaller than the enclosure (4) on the outer edge and support the side walls. Step 6: Excavate pile pits at the bottom of the foundation pit where the two bridge piers occupy the land outline (2): Manually excavate pile pits (8) of the required depth at the bottom of the foundation pit (7) located below the land outline (2) of the two bridge piers and do a good job of side wall support. Step 7: Erect formwork supports at the opening of the pile pits: Erect formwork supports (9) at the openings of the two pile pits (8) to the required height; Step 8: Place the steel cages into the formwork support: Make two steel cages (10) of the required length, temporarily close one side of the highway lane (1), use a crane to lift the two steel cages (10) and place them into the two sets of formwork supports (9) from the top of the two sets of formwork supports (9). After placement, open the closed side of the highway lane (1). Step 9: Use a concrete pump truck to pour concrete into the steel cage outside the highway: Drive the concrete pump truck (11) to the outside of one side of the highway lane (1), move the pump head to the top of the steel cage (10), and pour concrete into the top of the steel cage (10) until the formwork support (9) is filled. Step 10: After the steel cage is poured, it forms a concrete pile and is cured: After the two steel cages (10) that have been poured with concrete are dried and cured, they form two concrete piers (12). Step 11, Demolding: Remove the formwork supports (9) surrounding the two concrete piers (12); Step 12: Backfill the foundation pit: Backfill the foundation pit (7) with soil (13) manually, so that the backfill soil (13) covers the part of the two concrete piers (12) located in the foundation pit (7); Step 13: Backfill the tunnel: Use manual labor to backfill the tunnel (6) and the sloping pit (5) with backfill soil (13); Step 14: Remove the fence and restore: After the backfill soil (13) is used to backfill the foundation pit (7), tunnel (6) and inclined pit (5), remove the fence (4) erected in the isolation zone (3) and restore the original green plants after leveling the foundation pit (7).

2. The method for constructing bridge piers in the median strip of a busy existing highway as described in claim 1, characterized in that: In step one, the length of the outline (2) of each pier is 2 meters and the width is 1.2 meters, and the distance between the outlines (2) of the two piers is 5.6 meters.

3. The method for constructing bridge piers in the median strip of a busy existing highway as described in claim 1, characterized in that: In step two, the length of the fence (4) enclosed area is 12 meters, the width is 2.6 meters, and the height of the fence (4) is 2.5 meters.

4. The method for constructing bridge piers in the median strip of a busy existing highway as described in claim 1, characterized in that: In step three, a laser rangefinder is used to define the excavation location of the sloping pit (5). The bottom of the sloping pit (5) is 5 meters deep, 2 meters wide, and the slope of the sloping pit (5) is 20 degrees.

5. The method for constructing bridge piers in the median strip of a busy existing highway according to claim 1, characterized in that: In step four, the method for excavating the tunnel (6) is shallow buried tunneling. The tunnel (6) is 2.2 meters high and 2 meters wide.

6. The method for constructing bridge piers in the median strip of a busy existing highway according to claim 1, characterized in that: In step five, the foundation pit (7) has a depth of 5 meters, a length of 11 meters, and a width of 2.4 meters.

7. The method for constructing bridge piers in the median strip of a busy existing highway according to claim 1, characterized in that: In step six, the depth of both pile pits (8) is 5 meters.

8. The method for constructing bridge piers in the median strip of a busy existing highway according to claim 1, characterized in that: In step seven, the height of the template support (9) is 15 meters, and a connection and installation hole is provided on the side wall of the template support (9) 5 meters away from the bottom of the template support (9).

9. The method for constructing bridge piers in the median strip of a busy existing highway according to claim 1, characterized in that: In step eight, each steel cage (10) is divided into two parts, each 10 meters long. The bottom of the straight steel bars of each upper half of the steel cage is provided with external thread A, and the top of the straight steel bars of each lower half of the steel cage is provided with external thread B. The external threads A and B are opposite in direction. First, the lower half of the steel cage is hoisted into the top of the formwork support (9), and then the upper half of the steel cage is hoisted into the top of the formwork support (9). The two halves of the steel cage are connected by connecting sleeves with opposite screw holes at both ends at the connection installation hole. After the two halves of the steel cage are connected, the connection installation hole is closed.

10. The method for constructing bridge piers in the median strip of a busy existing highway according to claim 1, characterized in that: In steps twelve to fourteen, the backfilling method for the foundation pit (7) is to first fill the foundation pit (7) with backfill soil (13) to form two opposite slopes, so that the top of the slope is located outside the foundation pit (7) and relies on the inner edge of the enclosure (4) for support. Then, the tunnel (6) and the sloping pit (5) are backfilled. Subsequently, the excess backfill soil (13) located outside the foundation pit (7) is filled into the foundation pit (7) in layers.

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