Abstract:
Aiming at the problem that the potential sliding body space of the middle end slope of the open pit mining operation is limited, and the traditional slope stability calculation method is no longer applicable, the potential landslide mechanism of the deep slope of the stope is studied by numerical simulation method, and the spatial morphological equation of the slope surface and the sliding surface in the potential sliding body is fitted. Based on the three-dimensional limit equilibrium strip division method, the bottom surface of the sliding body is divided into unit micro-strips along the transverse and longitudinal directions. The force situation of the micro-strips in different areas of the spatial position of the sliding body and the top line of the slope is analyzed. Using the equivalent idea, the mechanical effect of each row of micro-strips is superimposed, which is equivalent to the micro-strips on the main sliding line of the sliding body. The equivalent shear strength parameters on the bottom interface of the main sliding line column are obtained, so as to establish a three-dimensional stability equivalent algorithm for restricting Carry out engineering application and design to recover coal resources. The results show that the potential landslide mode of the slope with weak layer is the combination of shear layer and bedding slide. The spatial morphology of the potential sliding surface is the combination of approximately ellipsoid and inclined plane. The three-dimensional stability coefficient of slope decreases gradually with the increase of the potential sliding body's strike limited length, showing an approximate quadratic parabola relationship. In the limited space of potential sliding body, the slope stability of various landslide modes is calculated, and the three-dimensional stability coefficients corresponding to different slope angles are greater than the two-dimensional stability coefficients. In the actual design of deep coal mining step, the slope stability decreases with the continuous reduction of +843 plate width. When the local slope angle is 25.58°, it just meets the requirement of safety reserve factor 1.2. Compared with the conventional method of slope stability analysis, this method can better reflect the three-dimensional stability of slope under the effect of three-dimensional clamping support, and can provide a new idea for the safety evaluation method of this kind of slope.