Research On Propagation Characteristics Of Stress Wave Propagation In Layered Rock And Vibration Source Localization

In our country,layered rock is distributed widely.The research on wave propagation in layered rock is a profound and significant issue,and a great number of practical large underground projects have close relation to the rock instability under stress or impulse load and the stress wave propagation in layered rock.Along with the increase of demand for minerals,deep mining has become a trend of development in the future's mining.The subject has also gotten more and more attention in the field of geotechnical engineering.Rock joints have an effect on the mechanical characteristic of rock mass.Consequently,it is a necessary way to analysis the effects of joints of layered rock to solve engineering problems.In this paper,we study the transmission of stress wave in layered rock media and vibration source localization to anisotropy of wave for layered rock thoroughly.First of all,we perform an experiment about stress wave propagation characteristics of layered rock sample.It respectively test the wave velocity of complete granite,basalt,sandstone and layer rocks of 0°,15°,30°,45°,60°,75°.We analyze the angle of joints and density to the influence of the wave velocity.Once more,we observer the change of micro-structure and crack before and after destruction by stereomicroscope,discussing which have an effect on wave velocity.Moreover,we study a source positioning method in double-layer incline media,which made full use of Huygens principle,isochron concept and the approximate determination method of refraction point which is widely used in engineering.The original double-layer horizontal media source positioning formula further promotion,we get a travel time equation which the depth and horizontal coordinates are separated,establish positioning model,correct the positioning results,and the applicable scope of the formula is presented.A numerical example proves that the method is effective.Last but not the list,we carry on three layer inclined media source location preliminarily,and analysis to combine with indoor experiment,getting an method in three and above layer source location.This paper has important theoretical significance and practical value to explore the propagation rules of wave in anisotropic medium and the wave velocity changes in the source localization.In order to establish a reasonable and suit for heterogeneous anisotropic rock media wave velocity model and accurate inversion source lay a theoretical foundation.