Isolation Effect Of Periodic Distributed Barriers On Plane Wave

The earthquake and vibration have great influence on the life of human beings.It is found that the periodic distribution structure has a good isolation effect.Therefore,this paper will study the isolation effect of periodic distributed pile and cavity.However,the research on the isolation effect of periodically distributed pile and cavity is mostly based on the finite number of pile and cavity as the calculation model,while the number of pile and cavity in actual projects is large.If the number of pile and cavity in the model is increased,the calculation and storage space will be greatly increased,sometimes even impossible to calculate.Therefore,this paper proposes the periodic indirect boundary element method(PIBEM)to study the isolation effect of a large number of periodic distributed pile and cavity.This method only needs to discretize one pile and one cavity,so the calculation and storage space are greatly reduced.At the same time,this method has a high calculation accuracy.In addition,in order to further enrich the types of seismic isolation structures,the scattering and isolation effects of infinite periodic topography on elastic waves are studied by using periodic indirect boundary element method.The main work is as follows:1.A periodic indirect boundary element method(PIBEM)based on twodimensional uniform load green’s function is established to solve the isolation effect of arbitrary number of periodic pile and cavity on elastic waves.Then,by comparing with the existing results,the correctness of the proposed method is verified.Finally,the impact of spacing between pile and cavity and stiffness of pile on isolation effect of pile and cavity is studied.At the same time,the attenuation frequency range of periodically distributed pile and cavity is studied.The numerical results show that with the decreasing of pile spacing and the increasing of pile stiffness,the isolation effect of periodic distributed pile increases.For cavity,the isolation effect is better when the spacing is smaller.2.A periodic indirect boundary element method(PIBEM)based on the threedimensional dynamic green function of concentrated load is established to solve the isolation effect of arbitrary number of elastic waves by periodic topography.Then,the accuracy of the proposed method is verified by comparison with the existing results.Finally,the impact of canyon spacing,canyon depth and frequency of incident wave on the isolation effect of periodic distributed canyon are studied.Numerical results show that the isolation effect of periodic canyon can reach more than 70% when P wave is incident,and the e isolation effect of periodic canyon can reach more than 80% when SV wave is incident.With the decreasing of canyon depth,canyon spacing and wave frequency,the isolation effect of periodic canyon is strengthened.