缓倾斜层状岩体单轴压缩力学行为的颗粒流数值模拟

PARTICLE FLOW CODE NUMERICAL SIMULATION OF UNIAXIAL COMPRESSION MECHANICAL BEHAVIOR OF GENTLY INCLINED LAYERED ROCK

针对不同层理面强度的缓倾斜层状岩体在单轴压缩试验中产生不同破坏形式的问题,以室内原岩单轴压缩试验结果为依据,采用颗粒流程序建立了缓倾斜层状岩体单轴压缩数值模型,研究了不同层理面强度条件下的缓倾斜层状岩体强度及破坏形式变化特征,并分析了不同工况时缓倾斜层状岩体微裂纹发育及演化规律和细观颗粒的位移演化规律,研究表明:当层理面强度远小于层理面间完整岩体强度时,层理面在一定程度上降低了层状岩体的整体强度,宏观破断面为沿层理面和贯穿层理面的折线型破断面;当层理面强度与层理面间完整岩体强度相近时,宏观破断面主要为光滑单斜面;当层理面强度远大于层理面间完整岩体强度时,层状岩体的强度由层理面间完整岩体的强度决定,宏观破断面主要为X型共轭破坏面。

Gently inclined layered rock masses display different mechanical behaviors at different strength of beddings in uniaxial compression tests. Particle flow code（ PFC） is used to establish numerical models for uniaxial compression in gently inclined layered rock masses based on the results of laboratory uniaxial compression tests on protoliths. The variations in the strength and failure modes of layered rocks under different strength of beddings are characterized. The development and evolution of micro-cracks and meso particles＇ displacement during uniaxial compression in gently inclined layered rocks with different strength of beddings are analyzed. The results show that when the strength of beddings is far smaller than that of the intact rock between beddings,the beddings reduce the strength of overall layered rock mass to a certain extent. The macroscopic fracture surface is a polyline type surface along the beddings and through the beddings. When the strength of beddings is similarly equal to that of the intact rock between beddings,the macroscopic fracture surface is a smooth slope that obliquely passes through a numberof beddings. When the strength of beddings is far bigger than that of the intact rock between beddings,the strength of the rock is mainly determined by the strength of the latter. The macroscopic fracture surface is a X-type conjugate failure surface.