1.引言许多关于岩石样品和模拟岩石样品的实验结果都证实了,在样品破裂前波速有一个明显的变化过程。但由于实验设备和技术所限,绝大多数实验样品都是比较小的,其尺度一般仅在几厘米到十几厘米,与野外实际情况相差较大。因此,有必要对大尺度样品进行实验 1. INTRODUCTION Many experimental results on rock samples and simulated rock samples confirm that there is a clear change in wave velocity before sample rupture. However, due to the limitations of experimental equipment and technology, the vast majority of experimental samples are relatively small, the scale is generally only a few centimeters to ten centimeters, and the actual situation in the field is quite different. Therefore, it is necessary to experiment with large-scale samples