【摘要】 对不同含水率条件下变片理倾角云母石英片岩试样进行波速测试，结合偏光显微镜和电镜扫描观察，探究声波在云母石英片岩中传播的变化机制。试验结果显示：当声波通过云母石英片岩时，其内部孔隙、裂隙沿片理面方向定向分布的特征以及矿物组构导致波速随其入射方向与片理面的夹角增大而减小；吸水过程中，水逐渐取代空气介质填充在云母石英片岩的空隙中导致波速总体随含水率的上升而增大，在水饱和度从50%上升到70%的阶段，由于水对云母石英片岩的软化作用和水分子自由振动的影响，声波传播速度下降，孔隙、裂隙的分布特征导致饱和状态下云母石英片岩波速受片理倾角影响减小、各向异性指数降低；脱水过程中，云母石英片岩表面的水分和孔隙、裂隙中的自由水蒸发，声波经过的空气介质增多，波速呈快速下降的趋势，但随着水的软化作用减弱，波速出现回升，且片理倾角越小的试样波速变化幅度越大。更多还原

【Abstract】 The wave velocity of mica quartz schist samples with varying schistosity under different water content is measured, and the change mechanism of sound wave propagation in mica quartz schist is investigated by polarizing microscope and electron microscope. The experimental results show that when sound waves pass through mica quartz schist, the distribution of internal pores and cracks along the direction of the schisting plane and the mineral fabric cause the wave velocity to decrease with the increase of the angle between the incident direction and the schist plane. In the process of water absorption, water gradually replaces the air medium to fill the void of mica quartz schist, resulting in the wave velocity generally increasing with the increase of water content. At the stage when the saturation rises from 50% to 70%, the wave velocity decreases due to the softening effect of water on mica quartz schist and the free vibration of water when it is not fully saturated, which weakens the propagation of sound waves. The distribution characteristics of pores and fractures lead to the decrease of wave velocity and the decrease of anisotropy index of mica quartz schist under saturation condition. In the process of dehydration, the surface water and free water in pores and cracks of mica quartz schist evaporate, the air medium through which sound waves pass increases, and the wave velocity decreases rapidly. However, with the weakening of the softening effect of water, the wave velocity increases, and the sample with smaller schistosity angle has a greater change in wave velocity.更多还原