在分离式霍普金森压杆实验装置上进行了花岗岩破坏的动静组合加载实验。通过对受载后岩样破碎块度进行筛分统计,得到了该加载条件下岩石破碎的粒度分布。在此基础上,通过理论计算公式,进一步得到了相应的破碎分形维数,分别探讨了静载荷和冲击载荷对分维数的影响。结果表明,动静组合加载作用下花岗岩破碎分维值在2.0~2.8之间;相同静载不同动载下,花岗岩的破碎分维值与试样的应变率有关,随应变率增大而增大;而在相同冲击动载下,静载荷变化对分形维数的影响不大。
Granite failure experiments under coupled static-dynamic load were carried out on SHPB (Split Hopkinson Pressure Bar) test equipment. Granularity distribution was obtained through screening and statistics of rock sample fragmention. Furthermore, the fractal dimension value was derived based on theoretical formula and the effect of static load and impact load on fractal dimension value was investigated, respectively. Results show that the fractal dimension values of granite under coupled static-dynamic load range from 2.0 to 2.8;under fixed static load and different dynamic load, the fractal dimension values are related with strain rate of samples and increase along with strain rate; under fixed dynamic load,static load has a little effect on fractal dimension values.