Influence of Soil Variability in SPT Data for Predicting the Bearing Capacity of Piles

Abstract

Standard penetration test (SPT) is one of the most commonly adopted methodologies to determine the soil profile at any particular site for calculating the bearing capacity of the pile foundations. Soil variability is inevitable. In this regard, the present study focusses on the statistical process of characterising the same based on the SPT data. This data was obtained from 20 boreholes at a site in Kolkata, which is proposed to adopt pile foundation for its upcoming structures. The vertical variability is characterised by a probability density function. The statistics of vertical variability comprising of mean and standard deviation are calculated, and the scale of fluctuation using the random field theory is obtained. The range of scale of fluctuation is found to be in good agreement with the globally accepted literature. This variability has been incorporated in predicting the bearing capacity of the piles for the proposed site using different correlations given by Meyerhof (1956), Aoki and De’Alencar (1975) and Decourt (1995). © 2021, Springer Nature Singapore Pte Ltd.