Numerical Modeling and Parametric Study of Piled Rafts Foundations Using Finite Element Software PLAXİS 2D

Year 2024, Volume: 8 Issue: 1, 14 - 22, 31.03.2024

Hossein Zoriyeh Aligholi

Abstract

This study presents a series of 2D analyses of piled rafts by varying the length, spacing, and diameter of the piles in the group. The simulated piled rafts are square in plan, and they are loaded vertically with a uniform load. The soil profile utilized for analysis represents the Avcılar district of Istanbul. The soil is treated as elasto-plastic material and idealized using the Mohr-Coulomb model in a drained condition, whereas the piles are modeled as embedded volume elements. For optimization purposes, a total of 64 different designs were created by varying pile diameter, pile length, and pile spacing as variables in pile raft foundation systems. To investigate how each variable affects deformation, modeling was carried out for pile diameters of 0.8, 1, 1.2, and 1.6 m and lengths of 15, 20, 25, and 30 m using 2D, 2.5D, 3D, and 4D ranges. As a result, the design with "D=0.8m, L=30, S/D=4" was found to be the optimal choice in terms of both price and performance.

Keywords

Deep foundation, Piled raft foundation, Optimization, Plaxis 2D

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