Dynamic analysis of pile foundations in time-domain using Lanczos vectors

An analytical procedure to obtain the response of pile-group in time domain is described. The procedure makes use of large domain for discretization along with coordinate transformation using Lanczos vectors. The responses are obtained in lime domain using an adaptive direct integration method. The scheme has the ability of error estimation due to temporal discretization and coordinate transformation. The procedure has been applied to three dimensional pile-group foundations. The compliance functions of the foundations have been obtained for all modes of vibration. The computational scheme has also been used to analyze the response of a machine foundation transmitting non-harmonic but periodic forces. The present method has all the advantages of time domain scheme which is local in space and time with small computational effort. (C) 1999 Elsevier Science Ltd. All rights reserved.