【作者】 沈志华；

【导师】 张彬；

【作者基本信息】 辽宁工程技术大学 ， 岩土工程， 2004， 硕士

【摘要】 声波衰减是研究岩石能量吸收性质的主要方法，它与岩石内部微裂纹及其变化有着密切联系，是岩石领域需要深入研究的课题之一。本人在分析前人研究成果的基础上，组建了一套单轴压缩岩石裂纹扩张声波衰减测量系统，编制了数据处理程序，采用脉冲传播和频谱比例测量方法，对完整和含模拟弱面花岗岩试件，进行了衰减与裂纹扩张性质的实验研究，取得了有价值的数据。实验结果表明：压致性张裂与剪切滑移对岩石声波Qp变化具有不同的影响效应。开始Qp随压力增加逐渐增大，当压力达到一定值时，Qp转为减小。岩石破坏前，压致性张裂Qp出现渐变性下降，而剪切滑移Qp则无较大变化，破坏时发生突变。对声波在岩石中传播的衰减机制进行了讨论，认为矿物颗粒边界和微裂纹表面的粘滞性摩擦，以及宏观裂纹的散射效应是引起声波衰减的主要机制。在应用方面，对岩体声波测量系统作了改进，对石膏夹层混凝土大型试件进行了检测。结果表明：系统基本满足矿山岩体声学性能测试的要求，适应于围岩松动范围，以及坝基较弱夹层的波速与衰减测量。更多还原

【Abstract】 Ultrasonic wave attenuation measure is an important method of researching the energy absorptance of rock. It relates with the variation of rock microcrack and is one of subjects to be researched continuously in rock area .On analyzing the results of other researchers, the author of this paper assembles a set of ultrasonic wave attenuation measure system of rock crack spread under untaxed pressure, makes up data program, using pulse transmition technique and spectral ratio method, with perfect and analogous crack basalt samples, performs experiment research in the relation of the attenuation and the crack spread, and obtains some of value data.The experiment results demonstrate that longitudinal on the variation of rock ultrasonic wave goodness. At first, Qp increases with pressure. When the pressure attains certain value, it change into reduce. Before the sample is broken up, longitudinal splitting Qp reduces gradually. But, shear glie Qp does not vary obviously and the sample occurs sharp destruction. The discussion of attenuation mechanism of ultrasonic wave transimtion in rock is performed. The viscosity friction of mineral grain and microcrack surface, and the scatter effect of macrocrack, are considered an prevailing attenuation mechanism. <WP=5>In application, rock ultrasonic wave measure system is reformed. It is fulfilled to detect large pollster layer concrete sample. The results show that the system can elementally satisfy the measure requirement of the acoustic quality of mine rock, and it is adaptable to the wave velocity and the attenuation measure of the loose area of rock, of weak layers under dam base.更多还原