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CN-121976843-A - Tunnel friction pile supporting structure penetrating through coal seam goaf and construction method

CN121976843ACN 121976843 ACN121976843 ACN 121976843ACN-121976843-A

Abstract

The invention relates to a tunnel friction pile supporting structure penetrating through a coal seam goaf, which comprises supporting friction pile bodies, wherein the supporting friction pile bodies are arranged at the lower end of a tunnel, a plurality of supporting friction pile bodies are arranged between adjacent supporting friction pile bodies, an arch grouting structure is formed between the adjacent supporting friction pile bodies, the end parts of the arch grouting structure are matched with the supporting friction pile bodies to be cast and molded, and the supporting structure of the tunnel friction pile penetrating through the coal seam goaf can effectively resist loose pressure, bias voltage and later sedimentation deformation of surrounding broken surrounding rocks by forming the arch grouting structure between the supporting friction pile bodies above a mined-out layer, and has shallower punching depth than other traditional modes, so that damage to a rock body structure is smaller, construction technical threshold and cost are reduced, complex stratum adaptability is enhanced, and deformation resistance and durability are improved.

Inventors

  • WANG LEI
  • XIA BINWEI
  • ZHANG CHENGPENG
  • LU YIYU
  • LIU HONGJIE
  • ZHANG YONGKUN
  • ZHANG XINGGUO

Assignees

  • 重庆大学

Dates

Publication Date
20260505
Application Date
20260309

Claims (10)

  1. 1. A tunnel friction pile supporting structure penetrating through a coal seam goaf is characterized by comprising supporting friction pile bodies (2), wherein the supporting friction pile bodies (2) are arranged at the lower end of a tunnel (1) and are multiple in number, an arch grouting structure (4) is formed between every two adjacent supporting friction pile bodies (2), and the ends of the arch grouting structures (4) are matched with the supporting friction pile bodies (2) to be cast.
  2. 2. The tunnel friction pile supporting structure penetrating through the coal seam goaf according to claim 1, wherein the arch-shaped grouting structure (4) comprises an arch-shaped body, a central grouting hole (5) and vertical grouting holes (7) which are formed in the arch-shaped body, the plurality of vertical grouting holes (7) are arranged in parallel, and the plurality of vertical grouting holes (7) are arranged on two sides of the central grouting hole (5).
  3. 3. The construction of claim 2, wherein the vertical grouting holes (7) have a vertical drilling depth, and the vertical drilling depths of the plurality of vertical grouting holes (7) are gradually shortened from the support friction pile body (2) to the central grouting hole (5).
  4. 4. The tunnel friction pile supporting structure penetrating through the goaf of the coal seam according to claim 2, wherein the arch body is provided with an oblique grouting hole (6), and the oblique grouting hole (6) extends downwards and obliquely from the upper end face of the arch body to the circumferential direction of the supporting friction pile body (2).
  5. 5. The tunnel friction pile supporting structure penetrating through the goaf of the coal seam according to claim 4, wherein the plurality of the inclined grouting holes (6) are arranged in parallel at equal intervals.
  6. 6. The tunnel friction pile supporting structure penetrating through a coal seam goaf according to claim 4, wherein the supporting friction pile body (2) comprises a friction pile lower section (21) and a friction pile upper section (22), circumferential steel bars (23) are arranged on the friction pile upper section (22) in the circumferential direction, and the ends of the circumferential steel bars (23) are installed in the inclined grouting holes (6).
  7. 7. The construction of claim 6, wherein the circumferential steel bars (23) are inclined upward in a vertical direction to form an angle A.
  8. 8. The tunnel friction pile supporting structure penetrating through the coal seam goaf according to claim 6, wherein annular supporting ribs (24) are arranged on the upper section (22) of the friction pile in the circumferential direction, and the annular supporting ribs (24) are attached to the lower ends of the circumferential reinforcing bars (23).
  9. 9. The tunnel friction pile supporting structure penetrating through the goaf of the coal seam according to claim 8, wherein the number of the circumferential steel bars (23) is plural, and the circumferential steel bars (23) are arranged in parallel and equidistant.
  10. 10. A construction method of a tunnel friction pile supporting structure penetrating through a coal seam goaf is characterized by comprising the following construction steps: s1, selecting the diameter and construction spacing of a supporting friction pile body (2) according to construction requirements, and vertically drilling holes to form supporting friction pile holes; s2, punching construction of a central grouting hole (5), a vertical grouting hole (7) and an inclined grouting hole (6) is carried out between adjacent support friction pile holes according to construction requirements, and the inclined grouting hole (6) is communicated with the support friction pile holes; S3, downwards mounting the reinforcement cage and the grouting pipe into a supporting friction pile hole, ensuring that the end parts of circumferential reinforcement bars (23) are mounted in the inclined grouting holes (6), carrying out preliminary grouting on the supporting friction pile hole, enabling the grouting height to reach the bottom position of the upper section (22) of the friction pile, and extracting the grouting pipe; S4, grouting construction is firstly carried out on the central grouting hole (5) and the vertical grouting hole (7), and then synchronous grouting is carried out on the upper parts of the inclined grouting hole (6) and the supporting friction pile hole.

Description

Tunnel friction pile supporting structure penetrating through coal seam goaf and construction method Technical Field The invention relates to the field of tunnel construction, in particular to a tunnel friction pile supporting structure penetrating through a coal seam goaf and a construction method. Background The tunnel passes through the goaf of the coal seam is a construction scene with high risk in geotechnical engineering, the core risk is caused by the problems of instability of a top plate, collapse of surrounding rock, gas leakage, water gushing, mud bursting and the like of the goaf, and the goaf often has hidden problems ‌ such as unclear distribution, complex cavity morphology, residual stress release and the like. The existing scheme generally adopts the following modes of backfilling goaf holes and then mechanically compacting, wherein when the goaf is far away from a tunnel, the compactness of the material is difficult to reach the standard, the deep compacting efficiency is low, the risk of water and soil softening exists, the construction period is long, and the cost is high; the method comprises the steps of adopting piling to penetrate through bedrock, enabling a goaf to penetrate through the goaf to directly reach the bedrock to provide supporting force when the goaf is far away from a tunnel, enabling the goaf to penetrate through the goaf to directly reach the bedrock, enabling construction technology to be difficult, low in efficiency, limited in geological conditions and high in cost, further enabling a large amount of slurry to be injected into the goaf through drilling holes, filling holes and cementing broken rock bodies to form a stone supporting structure, enabling slurry shrinkage and solidification hidden danger, slurry leakage and pollution problems, slurry loss under the conditions of fine particle stratum being difficult to penetrate, enabling construction period to be long and high in cost, enabling grouting amount to be huge, enabling the tunnel to penetrate through the goaf to be fully compact, enabling the goaf to be prevented and controlling water trouble to be achieved, and enabling the goaf to be far away from the tunnel in a traditional processing mode to be difficult in various construction and not beneficial to practical operation. Therefore, in order to solve the above problems, a tunnel friction pile supporting structure penetrating through a goaf of a coal seam and a construction method thereof are needed. Disclosure of Invention According to the tunnel friction pile supporting structure penetrating through the coal seam goaf, the arch grouting structure is formed between the supporting friction pile bodies above the goaf, loose pressure, bias voltage and later sedimentation deformation of surrounding broken surrounding rocks can be effectively resisted, the punching depth is shallower than that of other traditional modes, damage to a rock mass structure is smaller, construction technical threshold and cost are reduced, complex stratum adaptability is enhanced, and deformation resistance and durability are improved. The technical scheme for solving the technical problems is as follows: According to the tunnel friction pile supporting structure penetrating through the coal seam goaf, the tunnel friction pile supporting structure comprises the supporting friction pile bodies, wherein the supporting friction pile bodies are arranged at the lower end of a tunnel, the number of the supporting friction pile bodies is multiple, an arch grouting structure is formed between the adjacent supporting friction pile bodies, and the end parts of the arch grouting structure are matched with the supporting friction pile bodies to be cast. Further, the arch grouting structure comprises an arch body, a central grouting hole and vertical grouting holes, wherein the central grouting hole and the vertical grouting holes are formed in the arch body, the vertical grouting holes are arranged in parallel, and the vertical grouting holes are arranged on two sides of the central grouting hole. Further, the vertical grouting holes have vertical drilling depths, and the vertical drilling depths of the vertical grouting holes become shorter gradually from the supporting friction pile body to the central grouting holes. Further, the arch body is provided with an oblique grouting hole, and the oblique grouting hole extends downwards and obliquely from the upper end surface of the arch body to the circumferential direction of the supporting friction pile body. Further, the oblique grouting holes are multiple, and the oblique grouting holes are arranged in parallel at equal intervals. Further, the friction pile body comprises a friction pile lower section and a friction pile upper section, circumferential steel bars are arranged in the circumferential direction of the friction pile upper section, and the end parts of the circumferential steel bars are installed in the oblique grouting holes. Furt