Construction structure for subsurface tunnel in hilly area

Abstract

The utility model discloses a construction structure for a subsurface tunnel in a hilly area, which comprises fender posts, an upward slope support and an advanced pipe shed protective arch, the fender posts are vertically supported on two opposite sides of a foundation pit and a tunnel entrance upward slope, and the bottom surfaces of the fender posts are positioned below an excavation line at the bottom of an open-cut foundation pit. A top ring beam is arranged on the top faces of the fender posts, the top face of the top ring beam is flush with the ground, the upward slope support is located at the end of an open excavation foundation pit, the advanced pipe shed protection arch is located at the boundary of light excavation and dark excavation, and the advanced pipe shed is arranged on the arch portion of an underground excavation tunnel. Compared with working well hole entering, a row of fender posts, anchor cables, waterproof curtains and the like can be reduced, and economic benefits are improved; the fender posts are used as the cover arch foundation, stability of the cover arch foundation can be guaranteed, and waste of transverse space caused by conventional foundation expansion is reduced.

Description

Technical Field

[0001] This utility model belongs to the field of tunnel construction technology, specifically relating to a construction structure for underground tunnels in hilly areas. Background Technology

[0002] Rapid tunnel entry refers to minimizing the time spent at the tunnel portal during tunnel construction to improve work efficiency. It is a complex and challenging task, facing numerous technical and environmental difficulties, such as: unstable geological conditions and strata variations at the portal; complex transitions between cut-and-cover and mined-excavation methods; portal instability due to insufficient initial support or lack of coordination between excavation and support; adaptation and matching of machinery during construction; various limitations during the retaining wall stage; drainage and seepage issues; construction safety risks; and cost losses, covering multiple aspects. Currently, the cut-and-cover tunnel entry conversion method still involves setting up a working shaft at the cut-and-cover end, and then commencing mined-excavation construction after the main structure of the working shaft or the frame beam is completed. This method has a long construction period, complex procedures, and relatively high costs. Furthermore, there is a significant risk of collapse when breaking through the retaining piles, further increasing construction risks and design difficulties. Utility Model Content

[0003] In view of this, the purpose of this utility model is to provide a construction structure for underground tunnels in hilly areas, so as to overcome the shortcomings of the prior art.

[0004] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0005] A construction structure for cut-and-cover tunnels in hilly areas is provided, comprising retaining piles, slope support, and advanced pipe roof arch support. The retaining piles are vertically supported on both sides of the foundation pit and the tunnel entrance slope. The bottom surface of the retaining piles is located below the bottom excavation line of the open-cut foundation pit. The top surface of the retaining piles is provided with a top ring beam, and the top surface of the top ring beam is flush with the ground. The slope support is located at the end of the open-cut foundation pit. The advanced pipe roof arch support is located at the boundary between the open-cut and cut-and-cover sections, and the advanced pipe roof is installed in the arch of the cut-and-cover tunnel.

[0006] As described in the construction structure for underground tunnels in hilly areas, the opposite sides of the retaining piles are respectively provided with corbel-type arch foundations, and the bottom end of the advanced pipe roof arch is supported on the corbel-type arch foundations.

[0007] As described in the construction structure for tunnel excavation in hilly areas, it also includes multiple anchor cables. The opposite faces of the retaining piles each have several horizontally arranged steel waist beams. One end of each anchor cable is fixed to the steel waist beam, and the retaining piles are anchored by the anchor cables.

[0008] The beneficial effects of this utility model's technical solution are:

[0009] Compared to using a working shaft for tunneling, this method can reduce the need for a row of retaining piles, anchor cables, and water-stop curtains, thus improving economic efficiency. Using retaining piles as the arch foundation can ensure the stability of the arch foundation and reduce the waste of lateral space caused by conventional enlarged foundations. Attached Figure Description

[0010] To further illustrate the above-mentioned objectives, structural features, and effects of this utility model, the following will describe this utility model in detail with reference to the accompanying drawings.

[0011] Figure 1 This is a longitudinal cross-sectional view of the opening in a preferred embodiment of the present invention;

[0012] Figure 2 This is a cross-sectional view of the opening in a preferred embodiment of the present invention;

[0013] In the diagram: 1. Retaining piles; 2. Advanced pipe roof arch support; 3. Top ring beam; 4. Corbel arch support foundation; 5. Anchor cables; 6. Steel waist beam. Detailed Implementation

[0014] The terms “utility model” and “this utility model” used in this specification are intended to broadly refer to all subject matter of this specification and any of the following patent claims. Statements containing these terms should not be construed as limiting the subject matter described herein or limiting the meaning or scope of any of the following patent claims. Furthermore, this specification does not attempt to describe or limit the subject matter covered by any claim of any particular component, paragraph, statement, or drawing of this application. The subject matter should be understood with reference to the entire specification, all drawings, and any of the following claims. This utility model may have other embodiments and be practiced or implemented in other ways. Moreover, it should be understood that the wording and terminology used herein are for illustrative purposes and should not be considered limiting.

[0015] The details of the present invention will now be discussed with reference to the accompanying drawings, which are illustrated by way of example only. In the drawings, similar features or components may be labeled with the same reference numerals.

[0016] The use of the terms "comprising," "having," and "including," and variations thereof, herein means to include the items listed herein, their equivalents, and additional items. While reference may be made in the description of the drawings to directions such as above, below, upward, downward, backward, bottom, top, front, rear, etc., for convenience, reference is made relative to the drawings. These directions are not intended to literally accept or limit the invention in any form. Furthermore, terms such as "first," "second," "third," etc., are used herein for illustrative purposes and are not intended to indicate or imply importance or significance.

[0017] See Figure 1 , Figure 2As shown in the preferred embodiment, the construction structure of this utility model for underground tunnels in hilly areas includes retaining piles 1, slope support, and advanced pipe roof arch 2. The retaining piles 1 are vertically supported on both sides of the foundation pit and the tunnel entrance slope. The bottom surface of the retaining piles 1 is located below the bottom excavation line of the open-cut foundation pit. The top surface of the retaining piles 1 is provided with a top ring beam 3, and the top surface of the top ring beam 3 is flush with the ground. The slope support is located at the end of the open-cut foundation pit. The advanced pipe roof arch 2 is located at the boundary between open and underground excavation. The advanced pipe roof is set in the arch of the underground tunnel.

[0018] The opposite sides of the retaining pile 1 are respectively provided with corbel-type arch foundations 4, and the bottom end of the advanced pipe shed arch 2 is supported on the corbel-type arch foundations 4.

[0019] Referring to the diagram, it also includes multiple anchor cables 5, and the opposite sides of the retaining piles 1 have several horizontally arranged steel waist beams 6. One end of the anchor cable 5 is fixed to the steel waist beam 6, and the retaining piles 1 are anchored by the anchor cables 5.

[0020] The following steps are included when implementing the above construction structure:

[0021] S1. The site is flat.

[0022] Level the site at the opening to ensure the flatness and stability of the construction site. If necessary, construct a first-level slope until the retaining piles are at the set elevation.

[0023] S2. Construct retaining piles and top ring beam.

[0024] Construct retaining piles for the cut-and-cover tunnel section, and extend the construction of the retaining piles to the transition area of ​​the mined-and-cover tunnel section to ensure the continuity and stability of the retaining structure.

[0025] S3. Within the area of ​​the retaining piles, the slope of the tunnel is supported as it is excavated, and the excavation is carried out to the elevation of the tunnel arch foundation.

[0026] With the protection of retaining piles, only the slope within the width of the foundation pit needs to be excavated, reducing the slope range and improving safety.

[0027] S4. Simultaneously excavate the open-cut foundation pit to the construction ramp elevation, and provide support as you excavate.

[0028] Construct steel walers and anchor cables according to the excavation area, and pour a hardened ramp at the excavation elevation to facilitate tunnel entry construction. Preferably, the construction slope is less than 12%.

[0029] S5. The corbel of the arch foundation is constructed using retaining piles as corbel supports.

[0030] For the two retaining piles at the foundation location, pre-embed the connecting steel bars, pour the arch foundation corbel, and connect it with the retaining piles as corbel support. This can reduce the space occupied by the shallow foundation arch corbel, avoid the risk of soft foundation, and avoid the settlement and deformation of the arch during the excavation of the tunnel.

[0031] S6. Cast the arch and construct the pipe shed;

[0032] S7. Commence tunnel construction.

[0033] This construction structure can be used for tunnel entry and exit construction in urban areas with undulating hilly terrain. It takes into account the unique topographical characteristics of hilly areas, simplifies the construction scale and costs, and forms stable conditions for tunnel entry on an uphill slope.

[0034] The above are merely preferred embodiments of the present utility model and are not intended to limit the implementation methods and protection scope of the present utility model. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A construction structure for excavated tunnels in hilly areas, characterized in that, The system includes retaining piles, slope support, and advanced pipe roof arch support. The retaining piles are vertically supported on both sides of the slope leading to the tunnel entrance. The bottom surface of the retaining piles is located below the excavation line at the bottom of the open-cut pit. The top surface of the retaining piles is equipped with a top ring beam, which is flush with the ground. The slope support is located at the end of the open-cut pit. The advanced pipe roof arch support is located at the boundary between the open-cut and cut-cut sections. The advanced pipe roof is installed in the arch of the cut-cut tunnel.

2. The construction structure for mined tunnels in hilly areas as described in claim 1, characterized in that, The opposite sides of the retaining piles are respectively provided with corbel-type protective arch foundations, and the bottom end of the advanced pipe shed protective arch is supported on the corbel-type protective arch foundation.

3. The construction structure for mined tunnels in hilly areas as described in claim 2, characterized in that, It also includes multiple anchor cables, and the opposite sides of the retaining piles have several horizontally arranged steel waist beams. One end of each anchor cable is fixed to the steel waist beam, and the retaining piles are anchored by the anchor cables.

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