Mechanical properties of rocks under dynamic loading

本文研究了岩石在动载作用下的力学行为，达到强度破坏点的时间约为1ms。这里的动态加载不是指冲击加载，而是指高速加载，开发了模拟动态加载试验的计算机程序，并对不同条件下的动态加载试验进行了模拟，以找到合适的试验方法。这一比例与前人用更复杂的方法得到的结果非常接近。4)试验操作简单、快捷，可以在现场进行。

Mechanical behaviour of rocks under the dynamic loading was investigated in this study, where time up to strength failure point is about 1 ms. Here, the dynamic loading means not impact loading, but high speed loading.Computer program to simulate dynamic loading tests is developed and simulation were carried out under various conditions to find an appropriate testing method. The results of computer simulation indicate that the dynamic properties can be obtained by a simple method ; impact the rock specimen by a hammer and measure the output of loadcell placed under the rock specimen.Experiments were carried out and results are summarized as follows.1) Uniaxial compressive strength of Kawazu tuff is about 32MPa, while compressive strength under dynamic loading is about 64 MPa.2) Uniaxial compressive strength of Tako sandstone is about 32MPa, while compressive strength under dynamic loading is about 63MPa.3) The ratio of dynamic and static compressive strength is found to be two for Kawazu tuff and Tako sandstone. this ratio is very close to the results of previous works by more complicated methods.4) The test can be carried out easily and speedy and it is possible to carry out in-situ.