Double-layer traffic descending tunnel construction method

Abstract

The invention discloses a construction method of a double-layer traffic down tunnel, a double-layer traffic road section sequentially comprises an east-west direction road section and a south-north direction traffic road section from top to bottom, and the construction method comprises the following steps that S1, a temporary steel bridge is erected above the south-north direction traffic road section, and the bridge surface of the temporary steel bridge is communicated with the east-west direction traffic road section; s2, forming a box culvert below the east-west traffic road section by adopting an open excavation method, and communicating the box culvert with the south-north traffic road section; s3, the east-west direction traffic road section and the south-north direction traffic road section above the down tunnel to be constructed are dismantled, then the down tunnel is constructed through an open excavation method, after construction is completed, passing of the east-west direction traffic road section is recovered, then the temporary steel bridge is dismantled, and passing of the south-north direction traffic road section is recovered; and S4, pipeline laying is conducted in the box culvert. Compared with the prior art, the safety risk of pavement settlement is eliminated, the construction period is shortened, the construction efficiency is improved, and the waterproof performance of the downward tunnel structure is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel construction, and in particular to a construction method for a double-layer traffic down tunnel. Background Art

[0002] An urban downhill tunnel refers to a tunnel located in a city for vehicles to travel in a specific downward direction. It is designed specifically for vehicles to pass quickly and safely from higher areas to lower areas. It can effectively alleviate urban traffic pressure, improve road capacity, reduce ground traffic congestion, and ensure the rapid passage of vehicles on urban main roads.

[0003] During the construction of urban downward tunnels, it is often necessary to ensure smooth traffic on the upper road section. At present, when the upper traffic section is divided into two layers, and from top to bottom they are the east-west traffic section and the north-south traffic section, a jacking box culvert is set on the east side to bury the pipeline, and the downward tunnel is constructed using the cover and excavation method to ensure smooth traffic on the upper road section.

[0004] However, the above construction has the following shortcomings: 1. Horizontal structural joints will be generated during the cover-excavation reverse construction method, resulting in low waterproof performance of the down tunnel structure, long construction period and low construction efficiency; 2. The jacking of the box culvert may cause safety risks such as road surface settlement in the east-west traffic section above. Summary of the invention

[0005] The present invention provides a double-layer traffic down tunnel construction method to solve the technical problems that when constructing a down tunnel under a double-layer traffic section, there is a safety risk of road surface settlement, a long construction period, low construction efficiency, and low waterproof performance of the down tunnel structure.

[0006] According to one aspect of the present invention, a method for constructing a double-deck traffic down tunnel is provided, which is used for constructing a down tunnel at a double-deck traffic section, wherein the double-deck traffic section includes an east-west section and a north-south traffic section from top to bottom, and comprises the following steps: S1, constructing a steel temporary bridge above the north-south traffic section, wherein the bridge deck of the steel temporary bridge is connected to the east-west traffic section; S2, forming a box culvert by open-cut method below the east-west traffic section, and connecting the box culvert to the north-south traffic section; S3, dismantling the east-west traffic section and the north-south traffic section above the down tunnel to be constructed, and then constructing the down tunnel by open-cut method, and after the construction is completed, resuming traffic on the east-west traffic section, and then dismantling the steel temporary bridge, and resuming traffic on the north-south traffic section; S4, laying pipelines in the box culvert.

[0007] As a further improvement of the above technical solution:

[0008] Furthermore, in step S2, the box culvert is divided into two sections, north and south, and open-cut construction is performed in sequence.

[0009] Furthermore, in step S2, the box culvert has dimensions of 15.3 m×6.9 m×36 m in width, height and length.

[0010] Furthermore, in step S2, after the box culvert is formed, a concrete pavement is constructed between the box culvert and the north-south traffic section.

[0011] Furthermore, step S3 specifically includes the following steps: S31, setting isolation piles in the middle of the foundation pit of the descending tunnel, and dividing the east-west traffic section and the north-south traffic section above the descending tunnel to be constructed into the south section and the north section according to the isolation piles; S32, dismantling the south section to carry out open-cut construction of the descending tunnel below the south section; S33, after the construction of the descending tunnel below the south section is completed, restoring the traffic of the east-west traffic section in the south section, and then dismantling the north section and isolation piles to carry out open-cut construction of the descending tunnel below the north section; S34, after the construction of the descending tunnel below the north section is completed, restoring the traffic of the east-west traffic section in the north section, dismantling the steel temporary bridge, and then restoring the traffic of the north-south traffic section.

[0012] Furthermore, in step S32, a rope saw is used for cutting when the southern end section is dismantled.

[0013] Further, in step S32, during the open excavation construction of the down tunnel below the southern section, the side structure of the down tunnel close to the isolation piles is a tongue-and-groove structure.

[0014] Furthermore, in step S33, a rope saw is used for cutting when dismantling the northern end section.

[0015] Furthermore, in step S33, the isolation piles are removed by cutting them in sections using a rope saw, with each section being 1m-2m high.

[0016] Furthermore, in steps S33-S34, when the traffic section is restored to traffic, the concrete strength of the top slab needs to reach 100% of the design strength, and the pavement paving and maintenance need to reach the opening conditions.

[0017] The present invention has the following beneficial effects:

[0018] The double-deck traffic down tunnel construction method of the present invention builds a steel temporary bridge above the north-south traffic section, and the bridge deck of the steel temporary bridge is connected with the east-west traffic section, so that when the down tunnel is constructed, vehicles in the east-west direction are diverted to pass through the steel temporary bridge, thereby ensuring smooth traffic on the east-west road; on the other hand, because the steel temporary bridge ensures smooth traffic on the east-west road, an open-cut method can be used to form a box culvert below the east-west traffic section, so as to fundamentally eliminate the safety risk of road surface settlement caused by jacking the box culvert, and the box culvert is connected with the north-south traffic section, so that when the down tunnel is constructed, vehicles in the north-south direction are diverted to pass through the box culvert, thereby ensuring smooth traffic on the north-south road; the east-west traffic culvert above the down tunnel to be constructed is removed. The access road section and the north-south traffic section provide construction conditions for the open-cut method, so that the open-cut method can be used for the down tunnel construction, thereby greatly shortening the construction progress and improving the construction efficiency, and ensuring the waterproof performance of the down tunnel. After the construction is completed, the east-west traffic section is restored to traffic, and then the steel temporary bridge is dismantled to restore the north-south traffic section to traffic; finally, the pipeline is laid in the box culvert; compared with the existing technology, this scheme ensures smooth traffic in the double-layer traffic section through the cooperation of the steel temporary bridge and the box culvert, so as to reduce the impact of the open-cut method construction of the down tunnel, and the open-cut formation of the box culvert eliminates the safety risk of road subsidence, shortens the construction period, improves the construction efficiency, and ensures the waterproof performance of the down tunnel structure. It is highly practical and suitable for wide promotion and application.

[0019] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0021] Figure 1 It is a flowchart showing the steps of the construction method of a double-layer traffic down tunnel according to a preferred embodiment of the present invention;

[0022] Figure 2 It is a structural schematic diagram of a double-layer traffic down tunnel construction method during construction according to a preferred embodiment of the present invention;

[0023] Figure 3 It is a partial structural schematic diagram of a double-layer traffic down tunnel construction method during construction according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0024] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0025] like Figure 1-Figure 3 As shown, the double-deck traffic down tunnel construction method of this embodiment is used for the down tunnel construction at a double-deck traffic section, and the double-deck traffic section includes an east-west section and a north-south traffic section from top to bottom, and includes the following steps: S1, constructing a steel temporary bridge above the north-south traffic section, and the bridge deck of the steel temporary bridge is connected to the east-west traffic section; S2, forming a box culvert by open-cut method below the east-west traffic section, and connecting the box culvert with the north-south traffic section; S3, dismantling the east-west traffic section and the north-south traffic section above the down tunnel to be constructed, and then using the open-cut method to construct the down tunnel. After the construction is completed, the east-west traffic section is restored to traffic, and then the steel temporary bridge is dismantled to restore traffic to the north-south traffic section; S4, laying pipelines in the box culvert.

[0026] like Figure 1-Figure 3 As shown, specifically, the double-deck traffic down tunnel construction method of the present invention is to build a steel temporary bridge above the north-south traffic section, and the bridge deck of the steel temporary bridge is connected with the east-west traffic section, so that when the down tunnel is constructed, the vehicles in the east-west direction are rerouted to pass through the steel temporary bridge, thereby ensuring smooth traffic on the east-west road; on the other hand, because the steel temporary bridge ensures smooth traffic on the east-west road, an open-cut method can be used to form a box culvert below the east-west traffic section, so as to fundamentally eliminate the safety risk of road surface settlement caused by jacking the box culvert, and connect the box culvert with the north-south traffic section, so that when the down tunnel is constructed, the vehicles in the north-south direction are rerouted to pass through the box culvert, thereby ensuring smooth traffic on the north-south road; the east culvert above the down tunnel to be constructed is removed. The west-bound traffic section and the north-south traffic section provide construction conditions for the open-cut method, so that the open-cut method can be used for the down tunnel construction, thereby greatly shortening the construction progress and improving the construction efficiency, and ensuring the waterproof performance of the down tunnel. After the construction is completed, the east-west traffic section is restored to traffic, and then the steel temporary bridge is removed to restore the north-south traffic section to traffic; finally, the pipeline is laid in the box culvert; compared with the existing technology, this scheme ensures smooth traffic in the double-layer traffic section through the cooperation of the steel temporary bridge and the box culvert, so as to reduce the impact of the open-cut method construction of the down tunnel, and the open-cut formation of the box culvert eliminates the safety risk of road subsidence, shortens the construction period, improves the construction efficiency, and ensures the waterproof performance of the down tunnel structure. It is highly practical and suitable for wide promotion and application.

[0027] Optionally, the east and west ends of the steel temporary bridge include cast-in-place piles, abutments, cap beams and columns, and piers are avoided from being designed in the foundation pit of the descending tunnel to avoid affecting the open excavation construction of the foundation pit.

[0028] In this embodiment, in step S2, the box culvert is divided into two sections, north and south, and is open-cut in sequence. Specifically, the box culvert is divided into two sections, north and south, and is open-cut in sequence, so that when the south section of the box culvert is open-cut, the south side road of the east-west section will be occupied, and vehicles in the east-west direction can pass through the steel temporary bridge and the north side lane of the east-west section; when the north section of the box culvert is open-cut, the north side road of the east-west section will be occupied, and vehicles in the east-west direction can pass through the steel temporary bridge and the south side lane of the east-west section; that is, the box culvert is divided into two sections, north and south, and is open-cut in sequence, which can greatly reduce the impact of the box culvert open-cut construction on road traffic.

[0029] In this embodiment, in step S2, the width, height and length of the box culvert are 15.3m×6.9m×36m. It should be understood that in the prior art, the jacking box culvert is used to lay pipelines, and its width, height and length are 7.2m×6.6m×50.82m, which cannot meet the requirements of north-south vehicle traffic. The width, height and length of the box culvert in this embodiment are 15.3m×6.9m×36m, and the box culvert width of 15.3m can meet the requirements of north-south vehicle traffic.

[0030] In this embodiment, in step S2, after the box culvert is formed, a concrete pavement is built between the box culvert and the north-south traffic section. Specifically, by building a concrete pavement between the box culvert and the north-south traffic section, it is ensured that during the open-cut construction of the down tunnel, north-south vehicles can be diverted to pass through the box culvert.

[0031] In this embodiment, step S3 specifically includes the following steps: S31, setting isolation piles in the middle of the foundation pit of the descending tunnel, and dividing the east-west traffic section and the north-south traffic section above the descending tunnel to be constructed into the south section and the north section according to the isolation piles; S32, dismantling the south section to carry out open-cut construction of the descending tunnel below the south section; S33, after the construction of the descending tunnel below the south section is completed, restoring the traffic of the east-west traffic section in the south section, and then dismantling the north section and isolation piles to carry out open-cut construction of the descending tunnel below the north section; S34, after the construction of the descending tunnel below the north section is completed, restoring the traffic of the east-west traffic section in the north section, dismantling the steel temporary bridge, and then restoring the traffic of the north-south traffic section. Specifically, isolation piles are used to provide adjustments for the open-cut construction of the down tunnel, and then the open-cut construction of the down tunnel is carried out under the southern and northern sections in turn to reduce the impact of the open-cut construction on road traffic. After the construction is completed, the steel temporary bridge can be dismantled to restore the road to its original state.

[0032] In this embodiment, in step S32, a rope saw is used for cutting when the southern section of the road is demolished. Specifically, when the southern section of the road is demolished by rope saw cutting, the impact on the surrounding roads can be reduced. It should be understood that rope saw cutting has the following characteristics: 1. The rope saw cutting construction does not require mechanical vibration, so it will not cause vibration impact on the surrounding roads; 2. The rope saw cutting is driven by electrostatics, which has low noise and reduces interference with the surrounding environment and personnel; 3. The rope saw cutting construction does not generate dust, avoiding dust pollution to the surrounding environment and roads; 4. The rope saw cutting uses precise cutting lines and high-speed rotating wire ropes, which can control the scope of road damage within a smaller range, which is conducive to protecting the structures and facilities of the surrounding roads.

[0033] In this embodiment, in step S32, when the down tunnel under the southern section is open-cut, the side structure of the down tunnel near the isolation pile is a tongue-and-groove structure. Specifically, when the down tunnel under the southern section is open-cut, the side structure of the down tunnel near the isolation pile is a tongue-and-groove structure, so as to facilitate connection with the down tunnel structure under the northern section. Optionally, the down tunnel structure includes a bottom plate, a side wall and a top plate.

[0034] In this embodiment, in step S33, a rope saw is used for cutting when the north end section is removed. Specifically, when the north end section is removed by a rope saw, the impact on the surrounding roads can be reduced.

[0035] In this embodiment, in step S33, the isolation piles are removed by cutting in sections using a rope saw, and each section is 1m-2m high. Specifically, the removal of the isolation piles by cutting in sections using a rope saw can reduce the impact on surrounding roads.

[0036] In this embodiment, in steps S33-S34, when the traffic section is restored to traffic, the top slab concrete strength needs to reach 100% of the design strength, and the road paving and maintenance need to reach the opening conditions to ensure the traffic safety of the traffic section.

[0037] like Figure 1-Figure 3 As shown, in one embodiment, the construction steps of a double-deck traffic down tunnel are as follows:

[0038] A four-lane steel temporary bridge is built above the north-south traffic section and on the north side of the east-west traffic section;

[0039] The box culvert is divided into two sections, north and south, for open excavation construction under the east-west traffic section. The width, height and length of the box culvert are 15.3m×6.9m×36m. In addition, within the scope of the steel temporary bridge widening road, a concrete pavement is built between the box culvert and the north-south road, and north-south vehicles are diverted to pass through the box culvert;

[0040] Design Φ1000@1300 reinforced concrete isolation piles in the middle of the down tunnel foundation pit, and use a rope saw to cut off the drilling range before construction;

[0041] The southern section is removed by cutting with a rope saw to carry out open excavation of the down tunnel below the southern section, and the side structure of the down tunnel near the isolation pile is tongue-and-groove;

[0042] After the construction of the down tunnel under the southern section is completed, the east-west traffic section of the southern section is restored, the northern section is removed by rope sawing, and the isolation piles are removed by rope sawing in sections to carry out the open excavation construction of the down tunnel under the northern section;

[0043] After the construction of the down tunnel under the northern section is completed, the east-west traffic section of the northern section will be restored, the steel temporary bridge will be removed, and then the north-south traffic section will be restored;

[0044] Pipe laying is carried out in the box culvert.

[0045] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. 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 constructing a double-layer traffic down tunnel, used for constructing a down tunnel at a double-layer traffic section, wherein the double-layer traffic section includes an east-west section and a north-south traffic section from top to bottom, and is characterized in that: The following steps are involved: S1: A temporary steel bridge is built above the north-south traffic section, and the deck of the temporary steel bridge is connected to the east-west traffic section; S2, a box culvert is formed under the east-west traffic section by open-cut method, and the box culvert is connected with the north-south traffic section; S3: demolish the east-west traffic section and north-south traffic section above the down tunnel to be constructed, and then use the open-cut method to construct the down tunnel. After the construction is completed, restore the east-west traffic section, then demolish the steel temporary bridge and restore the north-south traffic section; S4, laying of pipes in the box culvert.

2. The double-layer traffic down tunnel construction method according to claim 1 is characterized in that: In step S2, the box culvert is divided into two sections, north and south, and open excavation is performed in sequence.

3. The double-layer traffic down tunnel construction method according to claim 1 is characterized in that: In step S2, the box culvert dimensions are 15.3m×6.9m×36m in width, height and length.

4. The double-layer traffic down tunnel construction method according to claim 1 is characterized in that: In step S2, after the box culvert is formed, a concrete pavement is constructed between the box culvert and the north-south traffic section.

5. The method for constructing a double-deck down-going traffic tunnel according to any one of claims 1 to 4, characterized in that: Step S3 specifically includes the following steps: S31, setting isolation piles in the middle of the foundation pit of the down tunnel, and dividing the east-west traffic section and the north-south traffic section above the down tunnel to be constructed into a south section and a north section according to the isolation piles; S32, demolish the southern section to allow for open cut construction of the down tunnel beneath the southern section; S33, after the construction of the down tunnel under the southern section is completed, the east-west traffic section of the southern section will be restored, and then the northern section and isolation piles will be removed to carry out the open-cut construction of the down tunnel under the northern section; S34, after the construction of the down tunnel under the northern section is completed, the east-west traffic section in the northern section will be restored, the steel temporary bridge will be removed, and then the north-south traffic section will be restored.

6. The method for constructing a double-layer down-going traffic tunnel according to claim 5, characterized in that: In step S32, a rope saw is used for cutting when dismantling the southern end section.

7. The method for constructing a double-deck down-going traffic tunnel according to claim 5, characterized in that: In step S32, during the open excavation construction of the down tunnel below the southern section, the side structure of the down tunnel near the isolation piles is a tongue-and-groove structure.

8. The method for constructing a double-layer down-going traffic tunnel according to claim 5, characterized in that: In step S33, a rope saw is used for cutting when dismantling the northern end section.

9. The method for constructing a double-layer down-going traffic tunnel according to claim 5, characterized in that: In step S33, the isolation piles are removed by cutting them in sections using a rope saw, with each section being 1m to 2m high.

10. The construction method of a double-layer traffic down tunnel according to claim 5, characterized in that: In steps S33-S34, when the traffic section is restored to traffic, the concrete strength of the top slab needs to reach 100% of the design strength, and the road surface paving and maintenance need to reach the opening conditions.

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