Chapter 6 - A Coupling Procedure of Finite Element and Scaled Boundary Finite Element Methods for Soil–Structure Interaction in the Time Domain

Abstract

A coupling procedure of finite element and scaled boundary finite element (SBFE) methods is presented for three-dimensional dynamic analysis of unbounded soil–structure interaction in the time domain. Based on linear system theory, the acceleration unit-impulse response matrix of the unbounded soil calculated by the SBFE method is converted into time-independent matrices; thus, the time history of the unit-impulse response function of the unbounded medium can be replaced by a state-variable description. Interaction forces between unbounded soil and structure are evaluated by linear equations instead of time-consuming convolution integrals. Since only partial information on the unit-impulse response function is needed to capture the character of the unbounded medium, and the history of the response function can be truncated, the computational effort spent in the SBFE method can be reduced. The accuracy of the procedure can be controlled with prescribed parameters. Numerical examples of foundation responses agree with previous results and are more efficient than the direct convolution integral method.