Anti-sidesway foundation for deep soft soil tunnel

Abstract

The utility model provides an anti-sidesway foundation for a deep soft soil tunnel. The foundation comprises a shield tunnel and a plurality of bearing structures arranged in the length direction of the shield tunnel at intervals. The shield tunnel is embedded in the gravel grouting foundation or the rock stratum foundation. And the shield tunnel is covered with a soil body filling layer. Each bearing structure comprises a bearing plate and a plurality of lower pile foundations. The bearing structure is an upper concave arc plate. And the shield tunnel is erected on the bearing structure. A gap exists between the bearing plate and the shield tunnel. The upper end of the lower pile foundation is connected with the bearing plate, and the lower end of the lower pile foundation is anchored into a gravel grouting foundation or a rock stratum foundation. The lower pile foundations in the same group are arranged at intervals in the direction perpendicular to the length direction of the shield tunnel. The tunnel anti-sidesway foundation under the deep soft soil condition can enhance the stability of a tunnel structure and reduce the risk of sidesway, so that the safety of a project is improved. The tunnel anti-sidesway foundation under the deep soft soil condition can effectively improve the tunnel anti-sidesway capacity, the service life of a tunnel can be prolonged, the maintenance and repair cost is reduced, and the sustainability of a project is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of geotechnical engineering construction, in particular to an anti-lateral displacement foundation of a deep soft soil tunnel. Background Art

[0002] When constructing a tunnel, it is inevitable to pass through various unfavorable geological areas, among which deep soft soil layers are extremely unfavorable for tunnel construction. When constructing a tunnel in a deep soft soil area, due to the weak engineering properties of the deep soft soil layer, the soil is prone to large lateral displacement and settlement under the action of construction loads, thus affecting the tunnel structure. Large lateral displacement will lead to instability and damage of the tunnel structure, affecting the safety and stability of the project, possibly causing serious accidents and casualties, and increasing the maintenance and repair costs of the project.

[0003] Traditional construction methods may not be able to effectively deal with the lateral displacement problem. In order to improve the safety and reliability of the project and reduce risks and costs, it is necessary to provide a new construction reinforcement structure and construction method to improve the tunnel's ability to resist lateral displacement. Utility Model Content

[0004] The utility model aims to provide a deep soft soil tunnel lateral displacement resistance foundation to solve the problems existing in the prior art.

[0005] The technical solution adopted to achieve the purpose of the utility model is as follows: a deep soft soil tunnel anti-lateral displacement foundation includes a shield tunnel and a plurality of supporting structures arranged at intervals along the length direction of the shield tunnel.

[0006] The shield tunnel is anchored in a sandstone grouting foundation or a rock foundation through a supporting structure. The shield tunnel is buried at a designed depth below the ground and is covered with a soil filling layer.

[0007] Each group of supporting structures includes a supporting plate and a plurality of lower pile foundations. The supporting structure is a concave arc plate. The shield tunnel is erected on the supporting structure. There is a gap between the supporting plate and the shield tunnel. The upper end of the lower pile foundation is connected to the supporting plate, and the lower end is anchored into the sandstone grouting foundation or the rock foundation. The same group of lower pile foundations are arranged at intervals along a direction perpendicular to the length direction of the shield tunnel.

[0008] Furthermore, the shield tunnel is connected to the supporting structure via expansion bolts.

[0009] Furthermore, the shield tunnel is a channel with a circular cross section formed by assembling six segments, wherein the six segments include three standard blocks, two adjacent blocks and one capping block.

[0010] Furthermore, the support plate is cast using waterproof concrete mortar.

[0011] The technical effects of this utility model are unquestionable:

[0012] A. The anti-lateral displacement foundation of the tunnel under deep soft soil conditions can enhance the stability of the tunnel structure, reduce the risk of lateral displacement, and thus improve the safety of the project;

[0013] B. The tunnel anti-sway foundation under deep soft soil conditions can effectively improve the tunnel's anti-sway capability, help extend the tunnel's life, reduce maintenance and repair costs, and improve the sustainability of the project;

[0014] C. The materials and equipment used in the tunnel lateral displacement resistance foundation construction method under deep soft soil conditions are common on the construction site and are suitable for actual projects;

[0015] D. The device is reasonable, the construction operation is convenient and quick, and it has high feasibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of the device structure;

[0017] Figure 2 It is a front view of the device;

[0018] Figure 3 is a side view of the device;

[0019] In the figure: it includes a shield tunnel 1, a supporting plate 2, and a lower pile foundation 3. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with the embodiments, but it should not be understood that the above subject matter of the present invention is limited to the following embodiments. Without departing from the above technical ideas of the present invention, various substitutions and changes are made according to the common technical knowledge and conventional means in the field, which should be included in the protection scope of the present invention.

[0021] Embodiment 1:

[0022] See also Figure 1 to Figure 3 This embodiment provides a lateral displacement resistance foundation for a deep soft soil tunnel, including a shield tunnel 1, and a plurality of supporting structures arranged at intervals along the length direction of the shield tunnel 1.

[0023] The shield tunnel 1 is anchored in a sandstone grouting foundation or a rock foundation through a supporting structure. The shield tunnel 1 is buried at a designed depth below the ground and is covered with a soil filling layer. The shield tunnel 1 is a channel with a circular cross section formed by assembling six segments. The six segments include three standard blocks, two adjacent blocks and one capping block.

[0024] Each group of supporting structures includes a supporting plate 2 and a plurality of lower pile foundations 3. The supporting plate 2 is cast with waterproof concrete mortar. The supporting structure 2 is an upper concave arc plate. The shield tunnel 1 is erected on the supporting plate 2. There is a gap between the supporting plate 2 and the shield tunnel 1. The shield tunnel 1 is connected to the supporting structure by expansion bolts. The upper end of the lower pile foundation 3 is connected to the supporting plate 2, and the lower end is anchored into the gravel grouting foundation or the rock foundation. The bottom and lateral loads of the tunnel are transferred to the foundation. The foundation has a large bearing capacity and can provide sufficient horizontal support force and anti-lateral displacement capability to prevent lateral displacement of the tunnel. The same group of lower pile foundations 3 are arranged at intervals in a direction perpendicular to the length direction of the shield tunnel.

[0025] Embodiment 2:

[0026] The main contents of this embodiment are the same as those of embodiment 1, wherein a transition zone exists in the area where the support plate 2 is connected to the side wall of the shield tunnel 1. A smaller radius is used to gradually transition the bottom plate to the shape of the shield tunnel 1 erected on the side wall of the support plate 2, ensuring the continuity and balanced force of the structure.

[0027] Embodiment 3:

[0028] The main contents of this embodiment are the same as those of Embodiment 1 or 2, wherein waterproof concrete mortar is used when casting the support plate 2, and the water-cement ratio ranges from 0.35 to 0.45, and appropriate amounts of water reducing agent, mineral admixture, reinforcing agent and other admixtures are added to enhance the waterproof performance.

[0029] Embodiment 4:

[0030] This embodiment provides a construction method of the foundation according to any one of Embodiments 1 to 3, comprising the following steps:

[0031] 1) Conduct geotechnical engineering survey on the construction site.

[0032] 2) Drill holes at the expected pile foundation location. According to the location and number of bored piles to be constructed, start the drilling rig and gradually make the holes reach the required depth. During the drilling process, an ultrasonic monitoring system is used to regularly check the diameter, horizontality and verticality of the holes.

[0033] 3) Grouting and placing steel cage at the pile hole. According to the design requirements, concrete is injected into the drilled hole through pipes or pumping equipment. The steel cage is placed during the concrete pouring process. After the pouring is completed, the pile top is leveled and trimmed. After the construction is completed and passed the quality inspection, the next step of construction can be carried out.

[0034] 4) The shield machine advances to form a shield tunnel 1. The shield machine cuts and crushes the soil and takes it out of the tunnel. The prefabricated reinforced concrete segments are assembled through the segment installation system of the shield machine. After the segments are installed, this step is repeated until the designed end of the tunnel.

[0035] 5) Grouting is performed at the lower part of the tunnel to form the support plate 2. Prepare the grouting material according to the designed proportion. Drill holes in the lower part of the tunnel structure to embed the grouting pipe, and transport the grouting material to the expected support plate 2 position through the grouting pump and fill it fully. The construction quality of the support plate 2 is monitored by ultrasound. After confirmation, the grouting pipe is removed to seal the reserved holes.

[0036] 6) The shield tunnel 1, the support plate 2, and the lower pile foundation 3 are connected as a whole by expansion bolts. Drill holes in the shield tunnel 1 vertically above each lower pile foundation 3 along the direction of the lower pile foundation 3, and cut and level the excess part after installation.

Claims

1. A deep soft soil tunnel anti-lateral displacement foundation, characterized by: It comprises a shield tunnel (1), and a plurality of supporting structures arranged in groups at intervals along the length direction of the shield tunnel (1); The shield tunnel (1) is anchored in a sandstone grouting foundation or a rock foundation through a supporting structure; the shield tunnel (1) is buried at a designed depth below the ground and is covered with a soil filling layer; Each group of supporting structures comprises a supporting plate (2) and a plurality of lower pile foundations (3); the supporting plate (2) is a concave arc plate; the shield tunnel (1) is erected on the supporting plate (2); there is a gap between the supporting plate (2) and the shield tunnel (1); the upper end of the lower pile foundation (3) is connected to the supporting plate (2), and the lower end is anchored in a sandstone grouting foundation or a rock foundation; the same group of lower pile foundations (3) are arranged at intervals along a direction perpendicular to the length direction of the shield tunnel.

2. The anti-lateral displacement foundation of a deep soft soil tunnel according to claim 1 is characterized by: The shield tunnel (1) is connected to the supporting structure via expansion bolts.

3. The anti-lateral displacement foundation of a deep soft soil tunnel according to claim 1 is characterized by: The shield tunnel (1) is a channel with a circular cross-section formed by assembling six segments; the six segments include three standard blocks, two adjacent blocks and one capping block.

4. The anti-lateral displacement foundation of a deep soft soil tunnel according to claim 1 is characterized by: The support plate (2) is cast using waterproof concrete mortar.

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