A Critical and Comparative Study on 2D and 3D Analyses of Raft and Piled Raft Foundations

Geotechnical Engineering Journal of the SEAGS & AGSSEA ISSN 0046-5828

Vol. 49 No.1 March 2018

A Critical and Comparative Study on 2D and 3D Analyses of Raft and Piled Raft Foundations

By V. Balakumar, Min Huang, Erwin Oh and A. S. Balasubramaniam

ABSTRACT: The piled raft foundation has gained a very high level of acceptance as a foundation system whenever settlement alone governs the design. In the design of piled raft many of the traditional methods could not be applied due to the complex nature of interactions involved. Hence there is a need to use detailed three dimensional finite element analyses for the final design. But in the initial stages of design a simpler but effective analytical process need to be used to save the computational efforts. Since the primary requirement in the piled raft design is the design of optimum pile group to achieve the desired settlement reduction, through number of trials, the applicability of simpler two dimensional analyses are examined to save the computational efforts during the initial trials. It was found that simple two dimensional analyses provide results of acceptable accuracy for the design office requirements.

KEYWORDS: Plane strain, Axisymmetric, ANSYS, PLAXIS.