CN-116927824-B - Front pre-splitting and rear grouting reinforcement supporting structure and method for severe underground environment

Abstract

The invention discloses a pre-fracturing post-grouting reinforcement support structure and method for a severe underground environment, which belong to the technical field of underground support, and are characterized in that pre-fracturing holes and grouting holes are respectively and vertically arranged around a rock stratum space in a severe roof, a hole protection steel pipe with a single side opening and an opening direction facing the rock stratum space is respectively placed in the holes, static expanding cracking agents are firstly injected into the pre-fracturing holes to enable the severe roof to be in a critical crushing state, cement-based materials are injected into the grouting holes to fill rock stratum cracks, and the pre-fracturing holes and the grouting holes are plugged after grouting is completed.

Inventors

• HUANG JINJING
• WANG YANHANG
• Kuang Luwei
• YAN GUOCHAO
• GE ZHIGUO
• BAI XUYANG
• ZHANG JIAWEI
• LI JIAJUN
• LI GANG
• Wu Kuangkuang
• LI BOYU

Assignees

• 太原理工大学

Dates

Publication Date

20260508

Application Date

20230908

Claims (4)

1. 1. A front pre-splitting and rear grouting reinforcement supporting structure of a severe underground environment is characterized in that pre-splitting holes (6) and grouting holes (7) are vertically arranged around a rock stratum space (2) in a severe roof (1), the number of the pre-splitting holes (6) and the number of the grouting holes (7) are more than or equal to 1, a hole protection steel pipe (5) with a single side opening is arranged in each of the pre-splitting holes (6) and the grouting holes (7), and the opening direction of the hole protection steel pipe (5) faces the rock stratum space (2) in the severe roof (1); The grouting device comprises a pre-cracking hole (6), a grouting hole (7), a hole opening plugging device and a hole opening plugging device, wherein the pre-cracking hole (6) is used for injecting a static cracking agent into a rock stratum space (2) to enable a severe top plate (1) to be in a critical crushing state; the hole plugging device is an explosion-proof electromagnet (3), one end of the explosion-proof electromagnet (3) is connected with the hole protection steel pipe (5), the other end of the explosion-proof electromagnet is in a closed state and is used for plugging the hole, and the explosion-proof electromagnet (3) is connected with an explosion-proof power supply (4); the explosion-proof electromagnet (3) is an explosion-proof electromagnet module (10) with a mortise hole in the middle, and the outside of the explosion-proof electromagnet module (10) with the mortise hole in the middle is connected with an explosion-proof power supply (4) through a mortise and tenon structure; an electromagnet expansion module is further connected between the outside of the explosion-proof electromagnet module (10) with the mortise and the explosion-proof power supply (4), and the electromagnet expansion module comprises an explosion-proof electromagnet module (8) with a tenon and an explosion-proof electromagnet module (9) with the mortise which are connected.
2. 2. The pre-presplitting post-grouting reinforcement support structure of a severe downhole environment according to claim 1, wherein one presplitting hole (6) and one grouting hole (7) are symmetrically arranged at two sides of the formation space (2), or a plurality of presplitting holes (6) and grouting holes (7) are uniformly distributed around the formation space (2) at intervals.
3. 3. The front pre-splitting and rear grouting reinforcement supporting structure of a severe underground environment according to claim 1, wherein a pressure sensor is arranged in the center of a pre-splitting area of a severe roof (1), the pressure sensor is connected with a grouting device through a controller, the grouting device is used for feeding back information of pressure load at the pre-splitting position of the roof through the pressure sensor, the grouting device is used for adjusting flow or pressure of a hydraulic grouting pump, and injection quantity of static cracking agent and cement-based materials entering a crack of a rock stratum space (2) at the roof is controlled.
4. 4. A method of reinforcing a pre-presplitting post grouting reinforcing structure based on a severe downhole environment as claimed in any one of claims 1-3, comprising the steps of: 1) The method comprises the steps of vertically arranging pre-cracking holes (6) and grouting holes (7) around a rock stratum space (2) in a severe top plate (1), wherein the number of the pre-cracking holes (6) and the number of the grouting holes (7) are more than or equal to 1; 2) Hole protection steel pipes (5) with single-side openings are respectively put into the pre-cracking holes (6) and the grouting holes (7), and the opening directions of the hole protection steel pipes (5) face to the rock stratum space (2) in the severe roof (1); 3) Firstly, injecting a static cracking agent into a hole protection steel pipe (5) in a pre-cracking hole (6) to further develop cracks in a rock stratum space (2) and enable a severe top plate (1) to be in a critical crushing state; 4) And injecting cement-based material into the formed rock stratum cracks through the grouting holes (7) to fill the rock stratum cracks, and plugging the pre-cracking holes (6) and the grouting holes (7) after the slurry is injected.

Description

Front pre-splitting and rear grouting reinforcement supporting structure and method for severe underground environment Technical Field The invention belongs to the technical field of underground support, and relates to a front pre-splitting and rear grouting reinforcement support structure and method for a severe underground environment. Background In the mine exploitation process, as the mine environment is complex and is influenced by rock characteristics and geological conditions, a plurality of special conditions appear on the underground roadway roof or roadway two secret society, which is not beneficial to underground supporting work. Moreover, corresponding means and equipment cannot be fully deployed under the complicated geographic conditions, and the roof or the two sides are easily broken. In the above case, the roof fall phenomenon is extremely liable to occur due to the roof. The roof fall phenomenon not only causes production delay, but also causes casualties due to accidents such as water permeation, gas outburst and the like. In the prior art, an anchor rope composite beam is mainly adopted for supporting, and a supporting structure is formed by hot-pressing common section steel, I-steel and steel belts. However, for a severe roof, the structure of the roof is unstable, and once the roof is broken, the anchor cable composite beam support can be damaged, so that underground accidents are caused, and the underground accident has a large potential safety hazard. Other supporting modes, such as supporting by adopting a telescopic bracket, have larger limitation, small supporting area and difficult to provide enough pressure to support the top plate, so that the supporting purpose cannot be achieved. Disclosure of Invention The invention overcomes the defects of the prior art, provides a front pre-splitting and rear grouting reinforcement supporting structure and method for a severe underground environment, and solves the problem that the existing severe roof or protective wall cannot be effectively controlled and supported. In order to achieve the above purpose, the present invention is realized by the following technical scheme. The front pre-splitting and rear grouting reinforcement supporting structure of the severe underground environment is characterized in that pre-splitting holes and grouting holes are respectively and vertically arranged around a rock stratum space in a severe roof, the number of the pre-splitting holes and the grouting holes is more than or equal to 1, and hole protection steel pipes with single-side openings are respectively arranged in the pre-splitting holes and the grouting holes, and the opening directions of the hole protection steel pipes face the rock stratum space in the severe roof; The pre-cracking hole is used for injecting a static cracking agent into the rock stratum space to enable the severe top plate to be in a critical crushing state, the grouting hole is used for injecting a cement-based material into the rock stratum space, and after grout injection is finished, orifice plugging devices are arranged at orifice positions of the pre-cracking hole and the grouting hole. Further, one pre-cracking hole and one grouting hole are symmetrically arranged on two sides of the rock stratum space, or a plurality of pre-cracking holes and grouting holes are uniformly distributed around the rock stratum space at intervals. Further, a pressure sensor is arranged in the center of the pre-cracking area of the severe top plate, the pressure sensor is connected with the grouting device through a controller, the grouting device adjusts the flow or pressure of the hydraulic grouting pump through information feedback of the pressure load of the pre-cracking position of the top plate, and the injection quantity of the static cracking agent and the cement-based material entering the rock stratum space crack of the top plate is controlled. Further, the orifice plugging device is an explosion-proof electromagnet, one end of the explosion-proof electromagnet is connected with the guard hole steel pipe, the other end of the explosion-proof electromagnet is in a closed state and is used for plugging the orifice, and the explosion-proof electromagnet is connected with an explosion-proof power supply. Furthermore, the explosion-proof electromagnet is an explosion-proof electromagnet module with a mortise hole in the middle, and the outside of the explosion-proof electromagnet module with the mortise hole in the middle is connected with an explosion-proof power supply through a mortise and tenon structure. Furthermore, an electromagnet expansion module is further connected between the outside of the explosion-proof electromagnet module with the mortise and the explosion-proof power supply, and the electromagnet expansion module comprises an explosion-proof electromagnet module with a tenon and an explosion-proof electromagnet module with a mortise which are connected. The reinforcin