不同粒径大理岩样声学特性的研究

基于不同粒径大理岩样进行了超声波测试,研究了浸水时间和宏观裂隙对波速的影响规律,以及岩样声学参数的离散程度。结果表明,浸水时间对岩样的纵波速度有很大的影响,但对横波速度影响甚微;宏观裂隙的存在降低了岩样的纵波速度,波幅降低程度与岩样破坏程度有关;随着岩石平均粒径的增大,岩石的声学参数先减小后增大,并非单调关系,而且动态泊松比的变化幅度明显高于其他声学参数,不能作为材料的力学参数表征岩石的变形特性。

Study on the acoustic property of marble specimens with different grains

Based on the supersonic measurement results of marble specimens with different grains,the influence law of soaking time and macroscopical fissure on wave speed,and the dispersion of acoustic parameters of specimens were carried out.The results show that soaking time has great influence on longitudinal wave speed of marble specimens,but no clear effect on the transverse wave speed.The macroscopical fissures can reduce the longitudinal wave speed,but the extent of reducing has relation with the failure extent of specimens.With the increase of specimens' average grain,the acoustic parameters of rock isn't a monotone function,and they reduce firstly and then increase,what's more,the changeable scope of dynamic Poisson's Ratio is higher than one of other acoustic parameters,and so it can't show the deformation property of rock as the mechanical parameter of material.