CN102797480A - Method for controlling bottom squeeze deformation of high-stress soft rock roadway by using discontinuous pressure-bearing grating concrete wall - Google Patents

Abstract

A method for discontinuous pressure-bearing grid concrete walls to control the deformation of floor drums in high-stress soft rock roadways, cutting and excavating inclined downward grooves at the bottom plates on both sides of the track and pouring discontinuous pressure-bearing grid concrete walls, and then pouring the discontinuous pressure-bearing grid concrete walls, and then The reinforced grid concrete is poured into the groove to form a wall structure that can withstand high compressive stress and high rigidity. On the one hand, the reinforced grid concrete that replaces part of the soft rock is cemented together with the weak rock mass of the floor, improving the integrity of the roadway floor and stiffness; on the other hand, the inward extrusion stress at the bottom corners on both sides of the roadway and the upward compressive stress in the floor will act on the grid concrete wall more evenly, so that the effects of the stress will cancel each other out and reduce the surrounding rock of the floor. At the same time, the wall structure can also resist the shear stress in the floor rock mass and prevent shear slip damage. The discontinuous arrangement of the grid concrete wall can effectively reduce the construction amount under the premise of satisfying the control effect, and the construction method is simple and fast.

Description

Method for controlling floor heave deformation of high-stress soft rock roadway with discontinuous pressure-bearing grid concrete wall

method field

The invention relates to a method for controlling the deformation of the floor heave of a high-stress soft rock roadway, in particular to a method for controlling the deformation of the floor heave of a high-stress soft rock roadway by using a discontinuous pressure-bearing grid concrete wall, which is suitable for controlling and treating the bottom plate of a coal mine roadway.

background method

Roadway floor heave deformation failure is a common failure mode in coal mine roadways, especially in deep high-stress soft rock roadways, and because the floor is the foundation of the roadway, severe floor heave deformation will cause the instability of the entire roadway and affect the normal operation of the roadway Use, increase maintenance investment, and even cause safety accidents. The prevention and control methods of roadway bottom heave can be generally summarized into two categories: reinforcement and pressure relief. Reinforcement methods include U-shaped steel retractable brackets with bottom arches, concrete masonry and arc plates and other full-section support methods, as well as bottom plate anchors, bottom plate grouting and anchor injection, etc.; pressure relief methods include pressure relief methods around the roadway, Such as opening and unloading pressure grooves on the bottom and loosening blasting in the deep part of the bottom plate. These methods reduce the amount of kick drum deformation under different conditions to varying degrees. However, when the roadway is in a state of high stress and the surrounding rock of the roadway is relatively weak and broken, the floor rock mass is prone to rheological deformation or shear slip deformation. The above methods cannot effectively control the floor heave deformation and damage of this roadway , and the construction process will hinder the normal use of the roadway and affect the construction period of the entire project.

Contents of the invention

Technical problem: The purpose of this invention is to overcome the deficiencies of the prior art and provide a non-continuous pressure-bearing grid concrete wall to control high-stress soft rock roadway with simple construction, less impact on the normal operation of the roadway, and good control effect Kick drum deformation method.

Technical solution: The method for controlling the deformation of the bottom drum of the high-stress soft rock roadway by the non-continuous pressure-bearing grid concrete wall of the present invention:

a. At the bottom plates on both sides of the track in the roadway, excavate grooves inclined 10°~30° toward the side of the roadway intermittently. The length of each groove is 3m~5m, the depth is 1m~2.5m, and the width is 0.5m. The spacing is 1m~2m;

b. After the excavation of the trench is completed, place the prefabricated steel bar grid in the trench, pour concrete, and vibrate compactly, and the discontinuous pressure-bearing grid concrete wall is composed of the trench, concrete and steel bar grid;

c. According to the length of the bottom plate treatment roadway as required, repeat steps a to b, and construct sequentially or at multiple points at the same time until the construction of the non-continuous pressure-bearing grid concrete wall is completed.

The steel bar grid is made by welding the main bars, stirrups and connecting bars in a cross, the ends of the main bars, stirrups and connecting bars are bent and overlapped, the lap length is not less than 0.1m and the connection is full welding; the specification of the main reinforcement is HRB335, the diameter is 0.022m, and the row spacing is 0.22m; The depth is the same, and the length of each steel bar grid is the same as the length of the groove;

Beneficial effects: due to the adoption of the above technical scheme, the use of discontinuous pressure-bearing grid concrete walls to control the deformation of the floor drum of high-stress soft rock roadways can not only effectively reduce the deformation of the floor drum of high-stress soft rock roadways, but also maintain the stability of the roadway floor , and the construction is simple and convenient, and has little impact on the normal use of the roadway. By using the discontinuous pressure-bearing grid concrete wall, the excavation of the trench can remove the high stress at the bottom corner of the roadway, and transfer the high stress to the deep surrounding rock, reducing the pressure of the surrounding rock of the roadway; The high-strength and high-rigidity bearing walls replace part of the weak rock mass, improve the integrity and rigidity of the roadway floor, and make the inward compressive stress at the bottom corners on both sides of the roadway and the upward compressive stress in the bottom plate act more evenly On the bearing wall, the effects of each other are offset to reduce the deformation of the surrounding rock of the floor. At the same time, the grid bearing wall can also resist the shear stress in the rock mass of the floor and prevent shear slip damage. The non-continuous layout of the grid concrete wall can effectively reduce the construction amount under the premise of satisfying the control effect, and can speed up the construction progress at multiple points at the same time, and also makes the application of this method adjustable according to the complexity of the actual situation on site .

Description of drawings

Fig. 1 is a schematic diagram of the structural arrangement of the present invention.

FIG. 2 is a top view of FIG. 1 .

Figure 3 is a layout diagram of the grid reinforcement.

In the figure: 1-roadway, 2-track, 3-side of roadway, 4-groove, 5-concrete, 6-main reinforcement, 7-stirrup, 8-connecting reinforcement.

Detailed ways

An embodiment of the present invention will be further described below in conjunction with accompanying drawing:

The method of the present invention utilizes the discontinuous pressure-bearing grid concrete wall to control the deformation of the bottom heave of the high-stress soft rock roadway, aiming at the problems that the floor of the roadway with high stress and weak surrounding rocks is prone to deformation and damage of the bottom heave, and the bottom plate is difficult to handle and construct. The bottom plate is intermittently excavated with inclined downward grooves and poured the discontinuous pressure-bearing grid concrete wall. The excavation of the trench can relieve part of the stress at the bottom corner of the roadway, and transfer the high stress to the deep part of the rock mass, reducing the surrounding rock pressure of the roadway. Then pour reinforced grid concrete in the groove to form a wall structure that can withstand high compressive stress and high rigidity. On the one hand, the reinforced grid concrete that replaces part of the soft rock is cemented with the weak rock mass of the floor, improving the floor of the roadway. On the other hand, the inward extrusion stress at the bottom corners on both sides of the roadway and the upward compressive stress in the bottom plate will act on the grid concrete wall more evenly, so that the effect of the stress will cancel each other out and reduce the stress. The deformation of the surrounding rock of the floor, and the wall structure can also resist the shear stress in the rock mass of the floor to prevent shear slip damage. The non-continuous layout of the grid concrete wall can effectively reduce the construction amount under the premise of satisfying the control effect, and can speed up the construction progress at the same time at multiple points, and can be adjusted according to the complexity of the actual situation on site. Specific steps are as follows:

a. First, at the floor on both sides of the track 2 in the roadway 1, intermittently excavate the groove 4 inclined 10°~30° toward the roadway side 3. The length of each groove 4 is 3m~5m, and the depth is 1m~2.5 m, the width is 0.5m, and the spacing is 1m~2m;

b. After the excavation of the trench 4 is completed, the prefabricated steel grid is placed in the trench 4, and then the concrete 5 is poured and compacted by vibrating. The groove 4, the concrete 5 and the steel grid together form a discontinuous bearing Pressed grid concrete wall; the steel bar grid is made by welding the main bars 6, stirrups 7 and connecting bars 8, and the ends of the main bars 6, stirrups 7 and connecting bars 8 are bent and overlapped. The connection length is not less than 0.1m and the joint is fully welded; the specification of the main reinforcement 6 is HRB335, the diameter is 0.022m, and the spacing between rows is 0.22m; the specification of the stirrup 7 and connecting reinforcement 8 is HPB235, the diameter is 0.022m, and the spacing is 0.22m; the width of each steel bar grid is the same as the depth of the groove (4), and the length of each steel bar grid is the same as the length of the groove 4;

c. According to the length of the bottom plate treatment roadway as required, repeat the above steps a to b, and construct sequentially or at multiple points at the same time until the construction of the non-continuous pressure-bearing grid concrete wall is completed.

Claims (2)

1. a discontinuous pressure-bearing grid concrete wall is controlled high stressed soft rock tunnel pucking deformation method, it is characterized in that:

A, in the tunnel base plate place, (1) middle orbit (2) both sides, be interrupted excavation to tilt 10 ° ~ 30 ° groove (4) of tunnel portion of group (3), every section groove (4) length is 3m ~ 5m, the degree of depth is 1m ~ 2.5m, width is 0.5m, spacing is 1m ~ 2m;

After b, groove (4) excavation are accomplished, prefabricated reinforcing bar grid is placed in the groove (4), fluid concrete (5), and vibration compacting constitute discontinuous pressure-bearing grid concrete wall by groove (4), mixed earth (5) with reinforcing bar grid jointly;

C, carry out the length that base plate is handled the tunnel as required, repeating step a to b, successively or multiple spot construct simultaneously and finish until discontinuous pressure-bearing grid concrete wall construction.

2. discontinuous pressure-bearing grid concrete wall control high stressed soft rock according to claim 1 tunnel pucking deformation method; It is characterized in that: described reinforcing bar grid is to be formed through welding production by main muscle (6), stirrup (7) and dowel (8) right-angled intersection; The tip bend overlap joint of main muscle (6), stirrup (7) and dowel (8), lap length is no less than 0.1m and the connection place is a full weld; Main muscle (6) specification is HRB335, and diameter is 0.022m, and an array pitch is 0.22m; The specification of stirrup (7) and dowel (8) is HPB235, and diameter is 0.022m, and spacing is 0.22m; The width of every reinforcing bar grid is identical with the degree of depth of groove (4), and the length of every reinforcing bar grid is identical with the length of groove (4).

Images