Settlement of footings in sand using dynamic soil properties

Most existing methods of estimating the settlement of footings in cohesionless soils under working stresses are empirical and based on correlations with field measurements of settlement. The result is considerable scatter and a lack of a basis for long term improvements. In this paper we propose a method of analysis based on equivalent-linear elasticity that involves measurement of real soil properties and uses simple analytical methods. We also propose methods to determine and/or estimate the needed soil properties. We report here on load tests of two footings and one plate with diameters ranging from 0.25 m to 0.91 m, in silty sand, in which measured settlement is compared with settlement predicted using the theory and soil properties determined in the field from seismic tests. We also compare measured settlements with values calculated with Schmertmann’s widely used method based on penetration testing.