阅读说明：本技术 一种差异角度底角预应力注浆锚杆与锚索协同稳定巷道帮底支护方法 (Roadway side-bottom supporting method adopting bottom angle prestress grouting anchor rod and anchor cable with different angles to cooperatively stabilize roadway ) 是由 经来旺 薛维培 经纬 郝朋伟 曹菲菲 于 2021-09-16 设计创作，主要内容包括：本发明涉及一种差异角度底角预应力注浆锚杆与锚索协同稳定巷道帮底支护方法,属于矿井支护领域,包括以下实施步骤：1)沿巷道底角与水平面呈45°方向钻取底角预应力注浆锚杆注浆孔；2)安装所述底角预应力注浆锚杆,施加预应力并完成注浆；3)沿巷道底角与水平面呈30°方向钻取底角预应力注浆锚索注浆孔；4)安装所述底角预应力注浆锚索,施加预应力并完成注浆。本发明利用差异角度安装预应力锚杆与锚索使二者之间呈一个锥形区域,对锚杆索进行注浆之后沿巷道方向形成一个钢筋混凝土锥形坝体,能够将很大一部分其上围岩承载结构传递过来的环向应力转移至围岩或煤深处,从而有效地抑制巷帮和底臌位移,保证矿井安全生产。(The invention relates to a roadway side and bottom supporting method by using a bottom angle prestress grouting anchor rod and an anchor cable with different angles to cooperatively stabilize, which belongs to the field of mine supporting and comprises the following implementation steps: 1) drilling a bottom angle prestressed grouting anchor rod grouting hole along the direction that the bottom angle of the roadway and the horizontal plane form a 45-degree angle; 2) mounting the bottom angle prestress grouting anchor rod, applying prestress and finishing grouting; 3) drilling a bottom angle prestress grouting anchor cable grouting hole along the direction that the bottom angle of the roadway and the horizontal plane form 30 degrees; 4) and installing the bottom angle prestress grouting anchor cable, applying prestress and finishing grouting. The invention utilizes the difference angle to install the prestressed anchor rod and the anchor cable to form a conical area between the prestressed anchor rod and the anchor cable, forms a reinforced concrete conical dam body along the roadway direction after grouting the anchor rod cable, and can transfer a great part of the hoop stress transmitted by the surrounding rock bearing structure to the surrounding rock or the deep coal, thereby effectively inhibiting the displacement of roadway walls and floor heave and ensuring the safe production of mines.)

1. A roadway side-bottom supporting method with the cooperative stabilization of a bottom angle prestress grouting anchor rod and an anchor cable at different angles comprises the following implementation steps:

1) drilling a first batch of bottom angle prestressed grouting anchor rod grouting holes along the direction that the bottom angle of the roadway and the horizontal plane form a 45-degree angle;

2) installing the first batch of bottom angle prestress grouting anchor rods, applying prestress and completing grouting;

3) drilling a second batch of bottom angle prestressed grouting anchor cable grouting holes along the direction that the bottom angle of the roadway and the horizontal plane form 30 degrees;

4) mounting the second batch of bottom angle prestress grouting anchor cables, applying prestress and finishing grouting; the implementation positions of the first batch of bottom angle prestress grouting anchor rods and the second batch of bottom angle prestress grouting anchor cables are the junction positions of the roadway side part and the bottom plate, all grouting holes are drilled by air hammers, the hole openings are plugged by quick-drying cement during grouting, and grouting slurry is configured by mineral inorganic reinforcing grouting materials according to a certain water-cement ratio.

2. The roadway side-bottom support method for cooperative stabilization of the bottom angle prestress grouting anchor rod and the anchor cable according to claim 1, wherein the depth of a grouting hole of the bottom angle prestress grouting anchor rod is 100mm more than the length of the anchor rod; the depth of the bottom angle prestress grouting anchor cable grouting hole is more than 100mm than the length of the anchor cable; the excessive part of the grouting hole is used for storing residual slag at the bottom of the hole.

Technical Field

The invention relates to the field of mines, in particular to a roadway side-bottom supporting method with the cooperative stabilization of a bottom angle difference prestress grouting anchor rod and an anchor cable.

Background

The method is characterized in that surrounding rock stress redistribution is caused when a roadway and a chamber are excavated, a surrounding rock loosening zone which is a surrounding rock loosening fracture area is generated, under the combined action of concentrated stress, underground water and high temperature, the soft rock roadway does not support and reinforce, so that the surrounding rock loosening zone can gradually diffuse to the deep part, the surrounding rock of the roadway is gradually destabilized and damaged, and finally a series of engineering disasters such as floor heave, convergence in roadway walls, roof collapse and the like occur, and the safety production of a mine is seriously threatened. Because the tunnel base angle position produces stress concentration more easily, can be fine after consolidating the tunnel base angle position weaken the "short slab effect" of country rock bearing capacity, so in order to restrain the lane group country rock to the inside displacement of tunnel and control the end heave, need set up stock and anchor rope in the tunnel bottom and consolidate and strut the country rock to control the deformation of lane country rock. Because the deformation of surrounding rock of a roadway cannot be effectively controlled by the conventional anchor cable support, it is important to provide a novel support method capable of effectively controlling the displacement of roadway sides and floor heave.

The invention forms a conical area by arranging the base angle anchor rods and the base angle anchor cables at different angles, the conical area is the area with the maximum stress concentration degree in the whole surrounding rock and the area with the most loose coal rock mass, after the prestressed anchor rod cables are arranged and grouting is carried out, the conical body becomes a span reinforced concrete conical beam, the base angle anchor rods and the base angle anchor cables transfer a large part of the circumferential stress transmitted by the bearing structure of the upper surrounding rock to the depth of the surrounding rock or coal through the reinforced concrete conical dam body formed by grouting, the stress and extrusion of the coal rock mass caused by the loosening of the coal rock mass by the water immersion of the bottom plate are avoided to a large extent, and the occurrence amount of floor heave is reduced to a large extent. In addition, after grouting in the conical area, the whole conical dam is formed along the roadway direction, because the upper end of the anchor rod cable is only in the obliquely upward direction due to the displacement direction of the roadway bottom corner position, and the lower end of the anchor rod cable is anchored in the deep coal rock mass, the cross reinforced concrete beam has stronger bearing capacity, more importantly, an approximately rigid displacement constraint is manufactured for the roadway side on the upper portion, a displacement boundary is formed, the circumferential stress transmitted by the aid of the side top structure in the integral bearing structure of the roadway is transmitted to the deep coal rock mass, the transmission of the stress to the roadway bottom plate is avoided, and great help is provided for reducing the floor heave degree. The roadway side-bottom supporting method based on the mechanical mechanism and based on the cooperative stabilization of the different-angle bottom-angle prestress grouting anchor rod and the anchor cable is formed.

Disclosure of Invention

The invention aims to solve the technical problem of providing a roadway side-bottom supporting method by using the bottom angle prestress grouting anchor rod and the anchor cable with different angles to cooperatively stabilize, thereby solving the problems in the background art.

The technical problem solved by the invention is realized by adopting the following technical scheme:

a roadway side-bottom supporting method for cooperative stabilization of a bottom angle prestress grouting anchor rod and an anchor cable at different angles comprises the following construction steps:

1) drilling a first batch of bottom angle prestressed grouting anchor rod grouting holes along the direction that the bottom angle of the roadway and the horizontal plane form a 45-degree angle;

2) installing the first batch of bottom angle prestress grouting anchor rods, applying prestress and completing grouting;

3) drilling a second batch of bottom angle prestressed grouting anchor cable grouting holes along the direction that the bottom angle of the roadway and the horizontal plane form 30 degrees;

4) mounting the second batch of bottom angle prestress grouting anchor cables, applying prestress and finishing grouting; the implementation positions of the first batch of bottom angle prestress grouting anchor rods and the second batch of bottom angle prestress grouting anchor cables are the junction positions of the roadway side part and the bottom plate, all grouting holes are drilled by air hammers, the hole openings are plugged by quick-drying cement during grouting, and grouting slurry is configured by mineral inorganic reinforcing grouting materials according to a certain water-cement ratio.

Preferably, according to the roadway side-bottom supporting method with the cooperative stabilization of the bottom angle prestress grouting anchor rod and the anchor cable at different angles, the depth of a grouting hole of the bottom angle prestress grouting anchor rod is 100mm more than the length of the anchor rod; the depth of the bottom angle prestress grouting anchor cable grouting hole is more than 100mm than the length of the anchor cable; the excessive part of the grouting hole is used for storing residual slag at the bottom of the hole.

Description of the drawings:

the invention will be further described with reference to the accompanying drawings.

Fig. 1 is a schematic diagram illustrating arrangement of anchor rods and anchor cables in a roadway side-bottom supporting method in which different-angle bottom angle pre-stressed grouting anchor rods and anchor cables cooperate to stabilize roadway side-bottom supporting according to an embodiment of the invention.

Fig. 2 is a schematic cross-sectional view illustrating arrangement of anchor rods and anchor cables in a roadway side-bottom supporting method by using different-angle bottom angle pre-stressed grouting of the anchor rods and the anchor cables in cooperation with stabilization of the anchor rods and the anchor cables.

In the figure: 1-soft rock roadway wall; 2-anchor cable for bottom corner of soft rock roadway; 3-soft rock roadway bottom angle anchor rod.

The specific implementation mode is as follows:

the technical solutions in the embodiments of the present invention will be described in detail below with reference to the drawings in the embodiments of the present invention. The described embodiments are only a part of the embodiments of the present invention, and all other embodiments obtained by those skilled in the art without any inventive work belong to the scope of the present invention.

Example (b):

as shown in fig. 1-2, a specific embodiment of the present invention provides a roadway side-bottom supporting method with cooperative stabilization of a bottom angle differential prestressed grouting anchor rod and an anchor cable, including the following steps:

a. drilling a bottom angle anchor rod hole with the specification ofThe hole depth of the drilled hole is 100mm longer than that of the anchor rod and the anchor cable because the slag is left at the bottom of the hole. The bottom angle anchor rod has the specification ofThe row spacing of the high-strength deformed steel anchor rods is 800mm, and an included angle of 45 degrees is formed between the high-strength deformed steel anchor rods and the horizontal direction. And (3) carrying out end anchoring on the anchor rod and applying prestress, wherein 1 quick-setting resin cartridge and 1 medium-speed resin cartridge are used, and the pre-tightening torque is 400 N.m.

b. And installing 10 bottom angle anchor rods into a group, and then grouting one by one. The water-cement ratio is 0.3: 1, grouting the anchor rod hole by using the mining non-base grouting material, wherein the grouting pressure is 1MPa, and the grouting time is 5 min.

c. Drilling a bottom angle anchor cable hole 24 hours after grouting the anchor rod hole, wherein the specification of the bottom angle anchor cable hole isThe hole depth of the drilled hole is 100mm longer than that of the anchor cable, and broken slag is left at the bottom of the hole; the anchor cable grid at the bottom angle isThe row spacing is 1600mm, and an included angle of 30 degrees is formed between the row spacing and the horizontal direction. And (3) carrying out end anchoring on the anchor cable and applying prestress, wherein 1 quick-setting resin cartridge and 2 medium-speed resin cartridges are used, the prestress is 300kN, and the prestress is not lower than 250kN after loss.

d. And installing 5 bottom angle anchor cables as a group, and then grouting one by one. The water-cement ratio is 0.3: 1, grouting the anchor cable hole by the mining non-base grouting material, wherein the grouting pressure is 2-3MPa, and the grouting time is 5-10 min.

And (3) construction results: the tunnel bottom angle anchor rod hole is drilled by 2500mm successfully, the bottom angle anchor cable hole is drilled by 6500mm successfully, and the installation work of anchoring the bottom angle anchor rod cable end and applying prestress is completed smoothly.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.