DISPERSION EFFECT OF ELASTIC WAVE IN JOINTED BASALTS
LIU Yonggui1，XU Songlin1，XI Daoying2，LI Guangchang3，ZHENG Wen1，DENG Xiangyun1
(1. CAS Key Laboratory for Mechanical Behavior and Design of Materials，University of Science and Technology of China，Hefei，Anhui 230027，China；2. Department of Earth and Space Science，University of Science and Technology of China，Hefei，Anhui 230026，China；3. Zhejiang East China Engineering Safety Technology Co.，Ltd.，Hangzhou，Zhejiang 310014，China)
Abstract：The jointed basalt is a kind of complicated material with large numbers of complex structures such as micro-cracks，micro-holes at the meso scale，and with non-uniformity and non-continuity properties at the macro scale，which leads to complexity of propagation rules of elastic wave in them. The analytical method based on the continuity can not be used to fully deal with those. In the present paper，for the study of mesostructure of rock on the law of wave propagation，cracks are taken for example and treated as inner boundaries. Based on the Green's function method，considering the introduction of suitable inner boundary conditions，and combined with method of boundary integral，the scattering of elastic wave is studied. Wave velocities of elastic wave predicted by the dispersion equation are compared to the results of laboratory experimental and in-situ test results，which show that the theoretical results in the present model are consistent well with in-situ test results；however，there is a wide gap with the results of laboratory experiment，which may be due to the differences between the environment of indoor experiment and in-situ test such as the stress state of rock samples，temperature and other factors. Furthermore，the mesostructures factors of the jointed basalt influencing on the dispersion effect are discussed，which results that the dispersion effect is strengthened with the increase in porosity and crack length in a certain range；all those results are guidance for in-situ test of acoustic and seismic wave.
