| Rock anchoring technology can improve the stress state of rock and soil,increase the shear strength of reservoir weak structural plane and the potential slipplane and enhance the integrity and stability of geotechnical structures. Thedetection of anchoring quality can generally be divided into traditional pull-out test,and nondestructive testing methods. In recent years, acoustic non-destructivetesting method gets more and more extensive applications. In order to improve thereliability of acoustic bolt detection evaluation, this thesis completes the followingaspects of work:(1) By the study of wave theory and the stress wave propagation law in thearchor, the stress wave transmission, attenuation and the energy distribution law inthe anchorage system is summarized. Based on one-dimensional elastic waveequation, uniform and uniform wave equations and their general solutions aredescribed in anchoring system. Embedded analysis of the stress wavescharacteristics in bolts is carried as academic bases of acoustic detection methodsand gist of test discrimination.(2)The response of bolt dynamic test has been simulate through ANSYS /LS-DYNA finite element program. The results demonstrate a variety of factors(including rock type, mortar location and extent of defects etc) on on the stresswave propagation and attenuation characteristics, and display the validity ofacoustic detection method. Comparative analysis of simulated and detected wavecan be used to improve the efficiency of anchoring quality tests. Also the simulatedresults can be used to build the database of dynamic test's response waveformsunder different conditions.(3)The dynamic response of non-destructive testing bolt in a hydropowerstation has been simulated. Though the similarity between simulated curve andmeasured curve in the vibration waveform, defect location and defect size, themethod of numeric simulation can be used to verify or improve the results of bolts'reinforcement quality evaluation issued during the field tests.
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