Dynamic Stiffness of Foundations: 2-D vs. 3-D Solutions.

摘要

Approximate formulae for the dynamic stiffness of embedded strip footings are developed through parametric studies. A comparison is then established between the static value of these stiffnesses and their frequency variation for two-and three-dimensional solutions. A plane strain model is demonstrated to be incapable of reproducing all the stiffness terms of a circular or square foundation. As a preliminary method of analysis,construction of similar formulae and graphs provides estimates of the natural frequency and effective modal damping provided by two-and three-dimensional finite element solutions. The magnitude of error in adopting a plane strain model may then be evaluated.