UNCERTAINTY AND RELIABILITY EVALUATION OF RAFT FOUNDATIONS VIA CHI-SQUARE TESTING

Abstract

The structural reliability of raft foundations is a critical factor in ensuring the safety and serviceability of buildings and infrastructure constructed on varying soil conditions. Traditional deterministic design approaches often overlook inherent uncertainties in soil properties, load variations, and construction practices, which may lead to unreliable predictions of foundation performance. This study applies the Chi-Square statistical method to evaluate the confidence and reliability levels of raft foundations by quantifying uncertainties in geotechnical parameters and load-bearing capacities. A database of soil test results and foundation performance data was analyzed to establish statistical distributions for settlement and bearing capacity. The Chi-Square method was employed to test the goodness of fit of observed data with expected theoretical distributions, enabling probabilistic assessment of reliability. The results indicate that ChiSquare testing provides an effective framework for identifying deviations in soil behavior, highlighting zones of higher uncertainty, and establishing confidence intervals for raft foundation performance. This probabilistic approach offers engineers a more reliable and data-driven basis for design and decisionmaking in geotechnical engineering, ensuring safer and more sustainable foundation systems