CN-121993237-A - Deep well coal mine roadway surrounding rock grading support construction method

CN121993237ACN 121993237 ACN121993237 ACN 121993237ACN-121993237-A

Abstract

The invention provides a deep well coal mine roadway surrounding rock hierarchical supporting construction method which comprises the steps of carrying out geological investigation and ground exploration on an area to be tunneled, determining distribution positions of joint stratum in the area to be tunneled, carrying out advanced detection on the area to be tunneled according to the distribution positions of the joint stratum, obtaining a rock mass of the area to be tunneled, determining geological features and structural integrity features of the rock mass, determining roadway surrounding rock grades according to the geological features and the structural integrity features of the rock mass, determining a supporting scheme matched with the roadway surrounding rock grades, carrying out supporting operation on the tunneled deep well coal mine roadway, and carrying out displacement monitoring on the supported roadway surrounding rock until the displacement of the supported roadway surrounding rock converges, so that the supporting operation is completed. The invention can grade the surrounding rock of the roadway and correspondingly adjust the supporting scheme, thereby not only improving the supporting efficiency, but also effectively improving the stability and the safety of the roadway.

Inventors

JIAO JIANKANG
WANG TAO
ZHANG ZHEN
LI WENZHOU
YANG HONGZHI
LI MING

Assignees

中煤科工开采研究院有限公司

Dates

Publication Date: 20260508
Application Date: 20251225

Claims (10)

1. The deep well coal mine roadway surrounding rock grading support construction method is characterized by comprising the following steps of: Geological investigation and ground exploration are carried out on the area to be tunneled, and the distribution position of the joint stratum in the area to be tunneled is determined; performing advanced detection on the area to be tunneled according to the distribution position of the joint stratum to obtain a rock mass of the area to be tunneled, and determining the geological features and structural integrity features of the rock mass; Determining a roadway surrounding rock grade according to the geological features and the structural integrity features of the rock mass, wherein the roadway surrounding rock grade comprises a plurality of grades; according to a mapping relation between a preset supporting scheme and a roadway surrounding rock grade, determining a supporting scheme matched with the roadway surrounding rock grade, and carrying out supporting operation on a tunneled deep well coal mine roadway; and (3) monitoring displacement of the supported roadway surrounding rock until the displacement of the supported roadway surrounding rock converges, and finishing the support.
2. The deep well coal mine roadway surrounding rock grading support construction method according to claim 1, wherein the step of determining the roadway surrounding rock grade according to the geological features and the structural integrity features of the rock mass comprises: according to the geological features and the structural integrity features of the rock mass, calculating the basic quality index of the rock mass; And according to the basic quality index of the rock mass and a preset mapping table of the roadway surrounding rock grade and the basic quality index, the roadway surrounding rock grade corresponding to the rock mass is matched and determined, wherein the roadway surrounding rock grade comprises primary surrounding rock, secondary surrounding rock, tertiary surrounding rock, quaternary surrounding rock and penta-level surrounding rock, and the stability of surrounding rock corresponding to the primary surrounding rock, the secondary surrounding rock, the tertiary surrounding rock, the quaternary surrounding rock and the penta-level surrounding rock is sequentially weakened.
3. The deep well coal mine roadway surrounding rock grading support construction method according to claim 2, wherein the geological feature of the primary surrounding rock is hard rock, the joint is not developed, no weak surface exists, the layered rock layer is a giant thick layer or thick layer, the structural integrity feature is a giant block integral structure, and the basic quality index is more than 550; The geological characteristics of the secondary surrounding rock are hard rock or hard rock Dan Ou soft rock, the soft rock comprises 1 to 2 groups of relatively developed joints, the layered rock layer is a medium-thick layer or thick layer, the structural integrity is characterized by a crushed stone-shaped crushing structure, and the basic quality index is more than or equal to 451 and less than or equal to 550; The geological characteristics of the three-level surrounding rock are soft rock, the soft rock comprises 1 to 3 groups of relatively developed joints, the layered softer surface is damaged, the structural integrity is characterized by a fragment-like mosaic structure, and the basic quality index is more than or equal to 351 and less than or equal to 450; The geological characteristics of the four-stage surrounding rock are soft rock, the four-stage surrounding rock comprises 2 to 3 groups of developed joints, the structural integrity is characterized by a fragment-shaped mosaic structure, and the basic quality index is more than or equal to 251 and less than or equal to 350; The geological feature of the five-stage surrounding rock is one of broken softer rock, broken soft rock, extremely soft rock and extremely broken rock, and the structural integrity is characterized by a boulder-shaped broken loose structure, and the basic quality index is less than or equal to 250.
4. The deep well coal mine roadway surrounding rock grading support construction method according to claim 3, wherein the support scheme comprises a primary support scheme, a secondary support scheme, a tertiary support scheme and a quaternary support scheme, the primary support scheme is matched with the primary surrounding rock and the secondary surrounding rock, and roadway surrounding rock grades corresponding to the secondary support scheme, the tertiary support scheme and the quaternary support scheme are three-stage surrounding rock, four-stage surrounding rock and five-stage surrounding rock respectively.
5. The deep well coal mine roadway surrounding rock grading support construction method according to claim 4, wherein the primary support scheme comprises the following steps: A plurality of anchor rod groups are installed on the surrounding rock of the tunnel after the excavation along the direction far away from the heading head, the row distance of two adjacent anchor rod groups is 800-1000 mm, the distance between two adjacent anchor rods in each anchor rod group is 800mm, and 14-18 anchor rods are arranged in each anchor rod group; arranging a plurality of entity anchor cable groups on roadway surrounding rock paved with anchor rod groups along a direction far away from a tunneling head, wherein the row spacing of two adjacent entity anchor cable groups is 1600-2000 mm, and the entity anchor cable groups are arranged in a 7-0-7 mode; after the supporting of the solid anchor cable group is completed, a concrete layer is sprayed in a range of 30m of a lagging tunneling working face to seal surrounding rock, and the thickness of the concrete layer is set to be 100+/-10 mm.
6. The deep well coal mine roadway surrounding rock grading support construction method according to claim 5, wherein the secondary support scheme further comprises the following steps on the basis of the primary support scheme: And (3) a plurality of high-pressure grouting anchor cable groups are arranged on roadway surrounding rock with a delayed tunneling working face in a range of 30-50 m after concrete layer spraying, the row spacing of two adjacent high-pressure grouting anchor cable groups is set to 1600+/-200 mm, and the plurality of high-pressure grouting anchor cable groups are arranged in a 6-0-6 mode.
7. The deep well coal mine roadway surrounding rock grading support construction method of claim 6, wherein the grouting material in the high-pressure grouting anchor cable group is nano modified composite single-liquid grouting material, and the particle size D95 is less than 10 mu m.
8. The deep well coal mine roadway surrounding rock grading support construction method according to claim 4, wherein the three-stage support scheme comprises the following steps: a plurality of entity anchor cable groups are arranged on the surrounding rock of the tunnel after the excavation and the mining along the direction away from the heading head, the row spacing of two adjacent entity anchor cable groups is 800mm, and the spacing of two adjacent entity anchor cables in each entity anchor cable group is 800mm; after the supporting of the solid anchor cable group is finished, spraying a concrete layer within the range of not more than 30m of a delayed tunneling working face to seal surrounding rock, wherein the thickness of the concrete layer is set to be 100+/-10 mm; And (3) a plurality of high-pressure grouting anchor cable groups are arranged on roadway surrounding rock with a delayed tunneling working face in a range of 30-50 m after concrete layer spraying, the row spacing of two adjacent high-pressure grouting anchor cable groups is set to 1600+/-200 mm, and the high-pressure grouting anchor cable groups are arranged in a form of 7-0-7.
9. The deep well coal mine roadway surrounding rock grading support construction method of claim 4, wherein the four-stage support scheme further comprises the steps of: arranging a plurality of grouting holes at the tunneling head, wherein the depth of each grouting hole is 10+/-1 m, and the grouting pressure is less than or equal to 20MPa; grouting and reinforcing the roadway side edges in a mode that deep holes and shallow holes are arranged at intervals, wherein the depth of the deep holes is 8000+/-1000 mm, the depth of the shallow holes is 4000+/-1000 mm, and grouting pressure is 5-8 MPa; after grouting reinforcement is completed, a plurality of entity anchor cable groups are installed on the excavated roadway surrounding rock at intervals along the direction away from the heading head, the row spacing of two adjacent entity anchor cable groups is 800mm, and the distance between two adjacent entity anchor cables in each entity anchor cable group is 800mm; after the supporting of the solid anchor cable group is finished, spraying a concrete layer within the range of 30m of a delayed tunneling working face to seal surrounding rock, wherein the thickness of the concrete layer is set to be 100+/-10 mm; And (3) a plurality of high-pressure grouting anchor cable groups are arranged on roadway surrounding rock with a delayed tunneling working face in a range of 30-50 m after concrete layer spraying, the row spacing of two adjacent high-pressure grouting anchor cable groups is set to 1600+/-200 mm, and the high-pressure grouting anchor cable groups are arranged in a form of 7-0-7.
10. The deep well coal mine roadway surrounding rock classification support construction method according to claim 1, characterized in that the deep well coal mine roadway surrounding rock classification support construction method further comprises the steps of: and before the tunnel tunneling is started, pre-grouting reinforcement is carried out on the area to be tunneled according to the distribution position of the joint stratum.

Description

Deep well coal mine roadway surrounding rock grading support construction method Technical Field The invention relates to the technical field of coal mine roadway tunneling, in particular to a deep well coal mine roadway surrounding rock grading support construction method. Background In the deep well coal mine tunnel tunneling process, surrounding rock stability is directly related to tunneling efficiency of a tunneling machine and safety of the whole operation process. Deep well environments have unique complexities that construct formations exhibiting diverse characteristics. The high ground stress is one of the remarkable characteristics in the deep well environment, and as the mining depth is increased, the ground stress is continuously increased, and a huge extrusion effect is generated on surrounding rock, so that the stress state of the surrounding rock is changed in a complex manner. Meanwhile, the joint density degree also has larger difference in different areas, the joint is used as a weak surface in the surrounding rock, the distribution and development degree of the joint directly influence the integrity and mechanical properties of the surrounding rock, and the surrounding rock conditions of each stage are obviously different due to the factors. Currently, in the related technology of deep well coal mine roadway tunneling, a unified supporting scheme is generally adopted for supporting surrounding rock of a roadway. However, for the area with poor surrounding rock conditions, the supporting strength and the supporting mode provided by the unified supporting scheme are difficult to meet the requirement of surrounding rock stabilization in the area, so that deformation, cracking, collapse and other phenomena of the surrounding rock occur in the tunneling process or in the subsequent using stage, the stable supporting effect cannot be realized, for the area with relatively good surrounding rock conditions, the supporting measures adopted by the unified supporting scheme are too conservative, the situation of excessive supporting exists, the supporting cost is increased, the consumption of supporting materials, the increase of construction working hours and the like are included, and the stress adjustment and release of the surrounding rock are influenced due to the excessive constraint of the supporting scheme on the surrounding rock, so that the long-term stabilization of the surrounding rock is not facilitated, and the integral supporting efficiency is reduced. Disclosure of Invention The present invention aims to solve at least one of the technical problems in the related art to some extent. Therefore, the embodiment of the invention provides a deep well coal mine roadway surrounding rock grading support construction method, which not only improves the support efficiency, but also effectively improves the stability and safety of the roadway and reduces the safety risk in the coal mining process. The deep well coal mine roadway surrounding rock grading support construction method provided by the invention comprises the following steps: Geological investigation and ground exploration are carried out on the area to be tunneled, and the distribution position of the joint stratum in the area to be tunneled is determined; performing advanced detection on the area to be tunneled according to the distribution position of the joint stratum to obtain a rock mass of the area to be tunneled, and determining the geological features and structural integrity features of the rock mass; Determining a roadway surrounding rock grade according to the geological features and the structural integrity features of the rock mass, wherein the roadway surrounding rock grade comprises a plurality of grades; according to a mapping relation between a preset supporting scheme and a roadway surrounding rock grade, determining a supporting scheme matched with the roadway surrounding rock grade, and carrying out supporting operation on a tunneled deep well coal mine roadway; and (3) monitoring displacement of the supported roadway surrounding rock until the displacement of the supported roadway surrounding rock converges, and finishing the support. In some embodiments, the step of determining the roadway surrounding rock grade from the geological and structural integrity characteristics of the rock mass comprises: according to the geological features and the structural integrity features of the rock mass, calculating the basic quality index of the rock mass; And according to the basic quality index of the rock mass and a preset mapping table of the roadway surrounding rock grade and the basic quality index, the roadway surrounding rock grade corresponding to the rock mass is matched and determined, wherein the roadway surrounding rock grade comprises primary surrounding rock, secondary surrounding rock, tertiary surrounding rock, quaternary surrounding rock and penta-level surrounding rock, and the stability of surrounding ro