The soil liquefaction during seismic loading generally has detrimental consequences on the stability of the structures supported on the ground. The past earthquakes have illustrated the liquefaction-induced damages such as tilting of buildings, uplift of buried structures, and failure of highway and railway embankments which inflicted heavy economic losses. The transient nature of the seismic loading tends to generate the large excess pore water pressure rapidly with very little time to dissipate them. This, in turn, leads to a significant loss in the strength and stiffness of the granular soil deposit with the water table at shallow depth.
The liquefaction remediation efforts have progressed extensively over the years with dozens of techniques being available now. The granular column (stone column) is a popular and successful mitigation method in practice. Though recent studies have found that the granular columns are effective in mitigating the liquefaction in general, the degree of resulting settlement still remains a major concern. The lateral deformations in the foundation soil are regarded as the primary reason for such large settlements.
The present study aims to augment the granular column with geosynthetic encasement to improve the shear resistance of the granular columns and ultimately evaluate the effectiveness of encased granular columns over ordinary granular columns without encasement. This is carried out by performing model studies in a 1-g shaking table and three-dimensional (3D) finite-difference numerical simulations. The results of the experimental and numerical analyses will be presented and the findings will be discussed in the seminar.