Efficient Dynamic Analysis of Multilayered System during Falling Weight Deflectometer Experiments

Abstract

This paper presents efficient solution techniques for the transient wave propagation in a multilayered soil medium due to axisymmetric dynamic loads applied on the surface. Analytical solutions of both displacement and stress fields in the interior of the layered stratum as well as on the surface are derived in the time domain from the elastodynamic equations using a direct method, in which Laplace-Hankel mixed transform and transfer matrix techniques are employed. In addition, an efficient numerical procedure, which utilizes the fast Hankel transform algorithm, is proposed to compute these analytical solutions. The presented solutions can be directly used to determine the transient dynamic responses of the multilayered medium subjected to a suddenly applied falling weight widely used in the nondestructive testing of pavement and layered subgrade systems. Illustrative examples demonstrate that these solutions can be readily computed and provide fairly accurate results.