Strengthening and reinforcing method of high-ground-pressure soft rock laneway by hierarchical grouting

Abstract

The invention relates to a strengthening and reinforcing method of a high-ground-pressure soft rock laneway by hierarchical grouting. Aiming at the deformation damage and crack distribution rules of laneway wall rock of high-ground-pressure soft rock, a hierarchical grouting mode for a shallow layer and a deep layer is adopted to hierarchically and emphatically strengthen and reinforce the shallow layer and the deep layer by grouting. The method comprises the following steps of: firstly, carrying out shallow-hole low-pressure grouting to a laneway shallow-layer gap development zone and then carrying out deep-hole high-pressure grouting to deep rock bodies; constructing shallow-hole grouting with small grouting pressure so that grout is scarcely diffused into the deep part, and grouting passages, such as a deep gap of the deep part and the like, are well preserved without blockage; and adopting a double-component chemical grout malisan with easy dispersion and strong permeability in constructing deep-hole grouting to realize deep high-pressure grouting on the basis of a formed grout-stopping shielding shell formed by former-period shallow-hole grouting so that the distribution compactness and the dispersion evenness of the grout in the deep grouting are improved, and the strengthening effect of the deep grouting on the wall rock is effectively improved. The method is simple and easy to implement.

Description

technical field [0001] The invention relates to a grouting reinforcement method for a mine roadway, in particular to a layered grouting reinforcement method suitable for a coal mine high ground pressure soft rock roadway. Background technique [0002] With the increasing demand for resources, many domestic mines have gradually entered the state of deep mining. After the mine enters deep mining, the roadway surrounding rock presents control characteristics such as increased ground stress, intensified deformation and damage, and difficult maintenance, which brings great threats and hidden dangers to the actual roadway construction safety. Surrounding rock grouting reinforcement technology can cement the loose and broken surrounding rocks into a whole, improve the strength of the rock mass, make the surrounding rock itself a part of the supporting structure, and the grouting reinforcement construction is convenient and low in cost, so it has become a widely used method in coal ...

AI Technical Summary

Problems solved by technology

The existing grouting reinforcement technology often adopts one-time grouting. Because the grouting pressure is small, the grout spreads only in the shallow crack development area, and the grouting depth is not enough; if the grouting pressure is high, it is easy to cause insufficient resistance in the shallow crack development area. If there is a large amount of grout running, grouting, and grout leakage, the actual grouting pressure cannot be increased, the amount of grouting is small, and the grouting effect is not good

In order to improve the grouting effect, many mining areas have proposed a secondary grouting method, but the original grouting pipe is often used for secondary high-pressure re-injection in the secondary grouting. The cracks are blocked by the first grouting slurry, the pressure rises quickly, the amount of the second grouting is small, the effect is not good, it is easy to run out of grout, and it is difficult to seal; The hole depth is the same as the first time. Although the grouting conditions have been improved, there are also the disadvantages of easy grouting or too little grouting during high-pressure grouting

Images