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In order to avoid the problems of the traditional prediction methods in the prediction of the support anti-destruction ability of the high stress soft rock roadway, a prediction method of the support anti-destruction ability of the high stress soft rock roadway based on machine learning is proposed. Firstly, according to the physical and mechanical properties of the rock, the strength characteristics of the soft rock are analyzed. At the same time, under the support of support construction model, the rheological characteristics of surrounding rock of soft rock roadway are analyzed, and the characteristics of high stress soft rock roadway are studied. Then, according to the plastic deformation mechanism of soft rock, the corresponding relationship among elastic zone, plastic hardening zone, plastic softening zone and plastic flow zone is determined, and the resultant force of surrounding rock movement to the free area is calculated to determine the optimal support time. The machine learning method simplifies the support structure of high stress soft rock roadway into a gourd structure model, calculates the external force, and determines the support structure quality parameter matrix of high stress soft rock roadway. By comparing the three conventional methods, it can be seen that the prediction accuracy of this method is higher under three kinds of different failure strength.

In order to explore the pressure relief effect of mining under protective seam on overlying strata in Jincheng Mining Area, the engineering background of mining 9# coal seam as the protective seam of 3# coal seam was studied. The effect of pressure relief of overlying coal and rock mass and the law of swelling deformation of coal mass in protected seam after mining of lower protective seam are studied by numerical simulation, and the effective protection scope is determined. The results show that after the mining of protective seam, the pressure relief effect of overlying coal and rock mass appears in different zones, and the pressure relief effect decreases with the increase of vertical distance from the working face. The inclined pressure relief angle of the protected seam is 63 degrees and the strike pressure relief angle is 60 degrees. The swelling deformation rate of the protected seam in the middle of the goaf is about 4‰, which is a stable pressure relief area. After field test, it was found by borehole television that coal of the protected seam appears separation fissure affected by mining. The coal seam gas parameters shows that the gas content and gas pressure of the protected seam are reduced to 50% and 60% before mining, respectively.