A seismic free field input model for FE-SBFE coupling in time domain

【摘要】 <正> A seismic free field input formulation of the coupling procedure of the finite elelnent(FE)and the scaledboundary finite-element(SBFE)is proposed to perform the unbounded soil-structure interaction analysis in time domain.Based on the substructure technique,seismic excitation of the soil-structure system is represented by the free-field motion ofan elastic half-space.To reduce the computational effort,the acceleration unit-impulse response function of the unboundedsoil is decomposed into two functions:linear and residual.The latter converges to zero and can be truncated as required.With the prescribed tolerance parameter,the balance between accuracy and effMency of the procedure can be controlled.The validity of the model is verified by the scattering analysis of a hemi-spherical canyon subjected to plane harmonic P,SVand SH wave incidence.Numerical results show that the new procedure is very efficient for seismic problems within a nor-real range of frequency.The coupling procedure presented herein can be applied to linear and nonlinear earthquake re-sponse analysis of practical structures which are built on unbounded soil.更多还原

【Abstract】 A seismic free field input formulation of the coupling procedure of the finite elelnent(FE)and the scaled boundary finite-element(SBFE)is proposed to perform the unbounded soil-structure interaction analysis in time domain. Based on the substructure technique,seismic excitation of the soil-structure system is represented by the free-field motion of an elastic half-space.To reduce the computational effort,the acceleration unit-impulse response function of the unbounded soil is decomposed into two functions:linear and residual.The latter converges to zero and can be truncated as required. With the prescribed tolerance parameter,the balance between accuracy and effMency of the procedure can be controlled. The validity of the model is verified by the scattering analysis of a hemi-spherical canyon subjected to plane harmonic P,SV and SH wave incidence.Numerical results show that the new procedure is very efficient for seismic problems within a nor- real range of frequency.The coupling procedure presented herein can be applied to linear and nonlinear earthquake re- sponse analysis of practical structures which are built on unbounded soil.更多还原