| Deformation and destruction of the coal rock slope with weak layer induced by blasting vibration seriously affects the open-pit coal mine safe and normal operation.The slope deformation and failure mechanism is not clear under the gravity stress and the blasting seismic wave,therefore,it is great significance to study the disaster evolution mechanism of coal rock slope with weak layer under the dynamic load.Paper based on Inner Mongolia Xilinhaote victory east 2 open-pit mine, the disaster-causing mechanism research of the coal rock slope with weak layer under the dynamic load is carried out by theory analysis,experimental study, and field monitoring method, The main research achievements is as follows:First of all,experimental study is carried out on carbonaceous mudstone weak layers, water influence of coal rock creep,direct shear test of different moisture content of mudstone which can get weak layer of internal friction Angle, cohesive force in different moisture content, axial pressure state, it provides a reliable mechanical parameters for slope numerical simulation, Meanwhile homemade coal rock slope vibration test system, weak layer to simulate the deformation failure process of slope under the influence of blasting vibration dynamic, revealing the blasting slope with weak layer under the action of deformation and failure mechanism, and put forward an inversion method of the natural vibration period of irregular coal rock slope; Secondly, the creep mechanical model of coal rock slope with weak layer is established. Based on the creep test data loading step by step, rheological equation and instability criterion of coal rock slope with weak layer is obtained under the influence of dynamic loading, At the same time, based on Ls-dyna and Geo-slope software platform, dynamic deformation characteristics of coal rock slope with weak layer or no weak layer and safety factor is analyzed under the influence of dynamic loading. And relationship of slope particle vibration acceleration and the critical vibration velocity is determined. Finally, radar and blasting vibration testing method is used in field monitoring research on the Datang victory east 2 open-pit mine, obtaining weak layer of slope safety threshold and the relations between the parameters of the blasting source under blasting loading, puting forward to main vibration frequency, vibration velocity of particles as the standard of safety evaluation index, Validating under blasting loading with weak layer peristalsis acceleration mechanism of deformation and failure of coal rock slope. |
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