砂岩和花岗岩的动态性能与能量耗散分析

利用直径100mm的分离式霍普金森压杆（SHPB）试验装置，对砂岩和花岗岩在应变率49~97s-1下进行了冲击压缩试验，对比分析了两种材料的动态力学特性和破坏形态.结果表明:两种材料的动态抗压强度，破坏程度和能量吸收随应变率的增大而增大，而花岗岩的能量耗散率则随着应变率增大而逐渐减少，呈现出较强的应变率相关性；初始弹性模量、峰值应变和砂岩的能量耗散率在3种应变率下的差别不大，应变率敏感性较弱.分析加载过程中两种试件能量吸收和耗散率的曲线，并从微观结构的角度对其动态破坏形态进行归纳分析.通过试验有效性的验证，证明试验较好地满足了均匀性假定. 

Analysis of Dynamic Properties and Energy Dissipation of Sandstone and Granite

To compare the dynamic mechanical properties and destruction forms of sandstone and granite with the strain rate ranging from 49s^-1to 97s^-1, impact compression tests were conducted using the split Hopkinson pressure bar(SHPB) test device with a diameter of 100mm. The results show that the dynamic compressive strength of the two materials, the extent of damage and energy absorption increased with the increase of strain rate, but the energy dissipation rate of granite gradually decreased with the increase of strain rate, and all of them show strain rate correlation; the initial elastic modulus, peak strain and energy dissipation rate of sandstone under three types strain rates show little difference and a weak strain rate sensitivity.By analyzing the energy absorption and dissipation rate curves in the loading process, the dynamic failure modes were analyzed from the perspective of microstructure. Through the verification of the test validity, it is proved that the test meets the assumption of uniformity better.