Practical Subgrade Model for Improved Soil-Structure Interaction Analysis: Software Implementation

Abstract

are relatively simple and easy-to-use approximations of the actual load-displacement behavior of the ground and have always played a significant role in foundation engineering research and practice. Winkler’s Hypothesis has been used almost exclusively for this purpose even though it has long been recognized as providing a poor approximation of actual subgrade behavior. The primary flaw of Winkler’s Hypothesis is the lack of coupling or connection between adjacent subgrade “springs.” Although numerous subgrade models that inherently incorporate “spring coupling” into their mathematical formulation have been developed, none has seen widespread adoption and use to date. This is due primarily to various issues that hinder their use with the commercially available structural analysis software used in routine practice. This paper is the second in a series of three that collectively illustrate the development and implementation of a new hybrid subgrade model with inherent spring coupling called the Modified Kerr/Reissner (MK/R) model. The MK/R model has been developed specifically to be both relatively easy to implement using commercially available structural analysis software as well as to evaluate using conventional geotechnical site-characterization methodologies. This particular paper is devoted to practical guidance as to how this is accomplished.