煤层底板破坏深度的声波CT探测试验研究

从煤层开采引起底板破坏一般规律出发， 探讨了底板岩体破坏与声波速度场的响应关系， 介绍了声波ＣＴ探测的原理与方法， 按采矿活动的关键阶段设计观测方案， 进行了试采面底板破坏深度的动态声波ＣＴ 探测试验． 采用纵波速度作为反演参量， 纵波速度的变化反映底板岩体的受力状态、结构变化以及破坏程度． 选用联合迭代重建方法（ＳＩＲＴ 法） 进行速度反演． 试验结果表明： 声波ＣＴ 能从空间角度动态探测底板破坏深度， 探测结果直观准确， 效果可靠．

Detection of the failure depth of coal seam floor by acoustic wave computer tomography

The response character of acoustic wave velocity field of coal floor rock mass failure is discussed according to the general principle of floor failure by mining.The detecting principle and methods of acoustic wave computer tomography are introduced.The dynamic detecting trial of failure depth on test mining face is made at different mining stages.The P wave velocity, whose changes reflect the press states, the changes in structure and the failure degree of floor, is used as inversion parameter.The revisional simultaneous iterative reconstruction techniques are applied to inversion.The trial results indicate that the acoustic wave tomography can detect the depth of floor failure dynamically in the form of area surveying.The results are precise, direct and reliable.