动静组合加载作用下块系岩体动力响应分析

深部复杂地质条件下，煤岩破碎更趋呈块系岩体，在动载作用下易于产生超低摩擦效应并失稳诱发煤岩动力灾害。采用FLAC-3D软件模拟块系岩体在垂直冲击载荷和水平静力共同作用下的动力响应，深入分析块系岩体超低摩擦效应发生机理，得到垂直冲击载荷和水平静力共同作用对工作块体位移和应力的影响规律，确定了块系岩体产生残余位移和超低摩擦效应的水平静力特征值条件。研究结果表明:仅垂直冲击载荷作用时，冲击载荷作用强度对残余位移影响并不明显；垂直冲击载荷和水平静力共同作用下，水平静力与残余位移曲线呈半抛物线关系；不同垂直冲击载荷作用下，产生残余位移的突变点不同，且当施加的水平静力处于不同特征值区间时，工作块体运动状态随之不同。

Dynamic response analysis on block rock mass under combined static-dynamic load

Under the deep complicated geological conditions, the coal rock tend to be broken as block rock mass, and under dynamic loading, the ultra-low friction effect is easy to be produced and the coal and rock dynamic disasters are easy to be induced with instability. The dynamic response of block rock mass under the combined effect of vertical impact load and horizontal static force was simulated by FLAC-3D software. The mechanism of ultra-low friction effect in block rock mass was analyzed, and the influence laws of block mass displacement and stress under the combined effect of vertical impact load and horizontal static force were obtained. The characteristic value conditions of horizontal static force to produce residual displacement and ultra-low friction effect in block rock mass were determined. The results showed that only under the effect of vertical impact load, the influence of impact load strength on residual displacement is not obvious. With the combined effect of vertical impact load and horizontal static force, the horizontal static force presents a half parabola relationship with the residual displacement. Under different vertical impact loading, the catastrophe points producing residual displacement are different. When the applied horizontal static force exists in different characteristic value interval, the motion state of working block mass is different accordingly.