Geotechnical Engineering Journal of the SEAGS & AGSSEA ISSN 0046-5828
Vol. 44 No.4 December 2013
Simulations of PVD Improved Reconstituted Specimens with Surcharge, Vacuum and Heat Preloading using Axisymmetric and Equivalent Vertical Flow Conditions
P. Voottipruex and D.T. Bergado, and W. Wongprasan
ABSTRACT: This paper presents the simulations of prefabricated vertical drain (PVD) improved reconstituted specimens with surcharge preloading (PVD), vacuum and surcharge with PVD (Vacuum-PVD), heat and surcharge with PVD (Thermo-PVD), heat plus vacuum and surcharge with PVD (Thermo-Vacuum-PVD) from large scale consolidometer tests in the laboratory. The flow conditions included axisymmetric conditions with horizontal (Kh) and vertical (Kv) permeabilities as well as equivalent vertical permeability (Kev) using backcalculated coefficient of horizontal consolidation (Ch). The simulation results indicated that the settlements and excess pore pressures obtained from axi-symmetric and equivalent vertical flows were similar at the same ratio of horizontal permeability at undisturbed zone to horizontal permeability at smear zone (Kh/Ks). The back-calculated Ch values were 1.93, 2.23, 4.17 and 4.38 m2/yr as well as the corresponding Kh/Ks values were 3, 2.7, 1.4, and 1.1, for PVD, Vacuum-PVD, Thermo-PVD and Thermo-Vacuum PVD, respectively. The Ch values increased while the Kh/Ks values decreased corresponding to PVD, Vacuum-PVD, Thermo-PVD, and Thermo-Vacuum PVD, respectively.
KEYWORDS: Prefabricated vertical drains (PVDs), equivalent vertical permeability (Kev), heat and surcharge preloading, numerical simulation
