中文摘要：

岩体是具有多种微结构的复杂体，具有明显的频散效应。过去的研究基本上将岩体中的孔隙率作为研究岩体微观结构的参数，这种方法无法考虑到岩体中细观缺陷的局部影响。本文选用水泥砂浆为参考材料，通过在试件中预制裂缝来研究含缺陷玄武岩的弹性波传播特性。对含不同裂缝的试样进行了5种频率的声波测试。结果表明：缺陷对玄武岩的弹性波频散效应影响很大，随缺陷所占比例的增大而增大。同时单轴加载下的弹性波测试则说明，在0～20MPa范围内，玄武岩弹性波波速随压力增大开始时候有一定幅度的升高，到8MPa以后由于玄武岩硬度相对较高，波速基本保持在一定水平。

英文摘要：

Rock is a kind of complex media with various micro-structures. It presents obvious frequency dispersion effect and its sonic velocity increases along with the incident frequency increase. Rock porosity ratio used to be used as a parameter describing the mechanical behaviors of rocks with micro-structure; however it is difficult to take into account the local effect of micro defect based on this approach. In this paper, taking cement ＇mortar as a reference material, using five different frequencies, the sonic velocity of basalt specimen with various prefabricated cracks was measured to study their dispersion effects. Results show that defect influence on rock frequency dispersion is intensive, and this tendency becomes more intensive along with the defect volume fraction increase. Sonic velocity of rock specimen with defect was also measured during uniaxial compression. Results show that with the applied loads increasing from 0 to 20MPa, sonic velocity in basalt and cement mortar increases obviously at the beginning, but it keeps constant when the load above 8MPa due to the higher hardness of basalt.