Uncertainty in Predicting Bearing Capacity of Piles in Sand Using SPT Data

Abstract

SPT is the most common testing methodology adopted in the field to gain idea about the stratigraphic profile at a site. The same is also employed directly or indirectly to determine the bearing capacity of proposed foundations. The present study aims at understating the usage of various correlations devoted to the correction of the field SPT data and their subsequent use in conjunction to the various correlations to determine the bearing capacity of pile foundation in sand. In this regard, a MATLAB code has been developed that can be used as ready-reference software to obtain the bearing capacity of the pile foundation in sand depending on the correction factor and bearing capacity correlations. Ten different forms of SPT correction correlation and six different bearing capacity correlations have been used in various combinations to reveal their effect on the determined bearing capacity, and the results of the same have been reported in the study. The degree of scatter in the output has been determined as an indirect measure to the degree of uncertainty in the usage of various correlations. The outcome of the present study can be further extended for reliability analysis of the usage of the correlations.