ANALYSIS OF EMBEDDED FOUNDATIONS BY SUBSTRUCTURE-DELETION METHOD

An alternative formulation of the substructure-deletion method for the dynamic analysis of three-dimensional embedded foundations of arbitra ry shape subjected to applied external forces and to incoming seismic waves is presented. The analysis is performed in the frequency domain, and the foundations are assumed to be rigid and embedded in a homogen eous viscoelastic half-space, with welded contact along the embedded s urface. This new formulation of the substructure-deletion method is ch aracterized by a boundary-integral approach for the analysis of the re moved soil inclusion, using Green's functions for an infinite viscoela stic medium, while half-space Green's functions are applied in the ana lysis of the flat half-space. Such a method was used in the computatio n of the impedance matrix and of the foundation input motion for squar e embedded foundations with different embedments. The results are cons istent with those obtained in previous studies, especially for the cas e of shallow foundations.