Estimation of Pile capacity has been one of the major challenging issues for geotechnical engineers in Bangladesh. Although various analytical and empirical methods and codes of practices are available to estimate the axial capacity of piles, the estimation has to be supported by pile load test results. However, in practice, being a costly, time-consuming, and risky approach, the number of pile load tests specified by code of practices is often truncated in many projects. Besides, a rigorous understanding of soil mechanics, local geology, and experiences are needed for the efficacious design of piles. This study focuses on estimation of load capacity and soil settlement for piles using the numerical modeling. A finite element based software, PLAXIS-3D, has been used for modelling of piles, to simulate pile load test for piles in this study. Four piles, having various dimensions and located at different parts of the country, are modelled to estimate load capacities. Those piles capacities are also estimated using different static and dynamic methods to validate the estimated pile capacities using PLAXIS model. For simplicity, for the shake of general practitioners, soils and concrete piles are modeled using Mohr-Coulomb, and Linear-elastic material models. The axial load capacity of the piles are estimated by different commonly practiced methods to determine pile capacity in Bangladesh (α or total stress method, β or effective stress method, λ or semi-empirical method, and BNBC 2020, based on SPT N value). Shear strength parameters of soils beneath and surrounding the pile are estimated based on empirical correlations based on SPT N value. Then, pile load tests are carried out for those Four piles to corroborate the load capacity and settlement values estimated by numerical modeling and other methods. The study shows that results from numerical modeling are agreeable with pile load test results and other commonly used methods. Therefore, numerical modeling of piles, which is easy to accommodate, could help the practicing engineers to design piles confidently and cost-effectively because the load-settlement behavior of all piles of the projects can be simulated using the numerical model. It could also decrease the number of pile load tests required for large projects and thus reduce the cost of the foundation.

Keywords : Pile capacity, Pile load test, Numerical modelling, Mohr-Coulomb, Linear-elastic.