Simulation of a Centrifuge Model Test of Pile Foundations in CDSM Improved Soft Clays

A fully coupled finite element computer code, TeraDysac, was used to study the influence of ground improvement around piles in a planned centrifuge model test. TeraDysac considers the coupled differential equations governing the behavior of the soil skeleton, pore water, and the piles. Bounding surface elastoplastic constitutive models are used to simulate the stress-strain behavior of soils in TeraDysac. The prototype of the centrifuge model consisted of 10 m of soft clay underlain by 8 m of dense sand. Four 0.36 m diameter single piles were simulated with various extents of CDSM around the piles. The simulations using TeraDysac involved base shaking of the entire deposit. Static lateral loading of slightly different piles using the computer code LPILE is presented in a companion paper (Sritharan and Huang, 2010). It was shown that CDSM around the piles is effective in reducing the lateral displacements of the piles during static and dynamic loading.