Nonlinear Settlement of Piled Rafts in Sandy Soil
Publication: International Journal of Geomechanics
Volume 21, Issue 11
Abstract
A hand-calculation method for estimation of nonlinear load–settlement response of piled raft foundations (PRFs) embedded in sandy soils is developed using three-dimensional finite-element (FE) analysis in which the elastoplastic constitutive behavior of the soil is modeled using the unified Clay And Sand Model (CASM). Three types of PRFs with rectangular, strip, and circular rafts and with a variety of pile dimensions and arrangements are considered in the study. The PRFs are assumed to be embedded in five different sands (Ottawa sand, Erksak sand, Sacramento sand, Portaway sand, and Decomposed Granite sand) with different elastic properties, critical state parameters, and relative densities. Systematic parametric studies are performed to develop equations for the estimation of the average nonlinear settlement of PRFs. The maximum and differential settlements are also estimated from the average settlement. The proposed equations require the relative density, elastic constants, and critical state friction angle of sand, and the piled raft geometry and properties as inputs. The settlement equations are applicable to PRFs of sizes similar to those considered in the study and can be used by practitioners for quick, initial estimation of PRF settlement as part of design calculations.
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Published In
International Journal of Geomechanics
Volume 21 • Issue 11 • November 2021
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© 2021 American Society of Civil Engineers.
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Received: Nov 2, 2020
Accepted: Jul 13, 2021
Published online: Sep 8, 2021
Published in print: Nov 1, 2021
Discussion open until: Feb 8, 2022
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