Treatise on Winkler Modulus of Subgrade Reaction and Its Estimation for Improved Soil–Structure Interaction Analysis

The paper pertains to the development of a new relationship expressing the Winkler modulus of subgrade reaction as a function of elastic parameters such as the modulus of elasticity and Poisson’s ratio of the foundation soil, and the relative rigidity of the foundation soil and the beam resting over the same. It ensures that the maximum values of beam deflection and bending moment computed by using both the theory of elastic continuum and lumped parameter modeling are either identical or very close to each other. In this respect the developed expression can be construed to be superior to those proposed by Biot and Vesic, which respectively predict correct values for only one of the quantities (either maximum bending moment or maximum deflection). In addition, the proposed model for subgrade modulus is applicable to multiple load conditions as well unlike the other two approaches as reported.