Nomographs for predicting allowable bearing capacity and elastic settlement of shallow foundation on granular soil

Abstract

Prediction of allowable bearing capacity of granular soil requires an intensive field investigation program. This research proposes empirical correlations to predict the allowable bearing capacity and elastic settlement of shallow foundation on granular soils. The current correlation using only standard penetration blow count number and soil unit weight an estimation of the bearing capacity can be attained. Such correlations can be used at the preliminary stage of estimating the allowable bearing capacity and elastic settlement of shallow foundation on granular soils and can help site engineers make immediate decisions in cases of field variations given in soil reports. Moreover, it can be used to create a map for the country in basis of the allowable bearing capacity based on few soil parameters. In this study, database of granular soil properties obtained from 650 boreholes collected from various locations in Sharjah, United Arab Emirates, were used to develop the governing predictive equations. Multiple regression analyses were conducted to develop mathematical models and nomographic solutions to predict the allowable bearing capacity and elastic settlement of shallow foundation. Following development of predictive equations, a set of data collected from 40 boreholes and 20 zone load tests was used to verify validity of the predictive model. The results indicated that the nomographs could effectively predict allowable bearing capacity within ± 15% confidence interval and the elastic settlement within ± 10%.