Method for controlling floor heave of dynamic pressure tunnel

Abstract

The invention discloses a method for controlling a floor heave of a dynamic pressure tunnel. The method comprises the following steps of: after symmetrically constructing drilling holes with different longitudinal included angles alpha in two side directions by taking the center of the tunnel cross section as the boundary on a tunnel base plate in a mining high-stress environment, mounting a hydraulic expansion anchor rod, injecting high-pressure water into the hydraulic expansion anchor rod, and stopping high-pressure water injection when the high-pressure reaches 30MPa; and constructing row by row according to the row distance until finishing the construction of the whole tunnel of the tunnel base plate, which is easy to have the floor heave in the mining high-stress environment. The anchoring force of the hydraulic expansion anchor rod does not change much with the differences of the properties of surrounding rocks, so the hydraulic expansion anchor rod is especially suitable for supporting the dynamic pressure tunnel base plate and provides a new way for controlling the floor heave of the dynamic pressure tunnel. The method has the advantages of simple construction method, convenient operation, low cost, low working intensity, high mounting efficiency, no pollution and remarkable economic efficiency.

Description

technical field [0001] The invention relates to a method for controlling the floor heave of a roadway, in particular to a method for controlling the floor heave of a roadway in a high-stress mining environment. Background technique [0002] Bass drum is a dynamic phenomenon that often occurs in coal mine shafts. After the roadway is excavated, the surrounding rock changes from a three-dimensional stress state to a two-dimensional stress state. Under the influence of complex concentrated stress, the floor rock layer is stretched and destroyed to form a floor heave. A large number of measured data show that about 2 / 3 of the roadway deformation is reflected in the floor drum. The main hazard of the bottom drum is that it reduces the section of the roadway, which affects pedestrians, transportation, water supply and drainage, and underground ventilation. [0003] The problem of bottom drum control in dynamic pressure roadway has always been one of the major problems plaguing t...

AI Technical Summary

Problems solved by technology

However, the above-mentioned bottom drum control methods have more or less defects such as slow construction speed, complicated process, high economic cost, limited control effect, and high labor intensity. For example, although the reinforced floor can play a certain role in suppressing the bottom drum, but In the dynamic pressure roadway, the material consumption is large, the support cost is high, and the engineering volume is large; under the condition of high stress and soft floor, the closed metal support bottom beam often cannot fully exert its bearing capacity, resulting in bulging into the roadway and losing The ability to control the bottom heave; in many cases, floor anchors fail due to poor anchorage in soft floor rock formations, insufficient anchoring force, or a mismatch between the amount of extension and the amount of floor heave; floor grouting can reinforce shallower layers of the floor, such as If the grouting fails to reach the failure depth of the floor rock layer, the upper reinforced rock layer will be lifted by the lower rock layer. Therefore, the role of grouting to control the bottom heave is also limited; and the construction procedures of the roadside filling method and the pressure relief coal pillar method are complicated , the time is long, the impact on the mining face is greater, and the control effect is very limited

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