Phenomenological simulation of the seismic response of ground stabilized with colloidal silica

Abstract

Passive stabilization is a novel technique for mitigating the risk of seismic liquefaction in the non-cohesive foundation soil of existing structures. It entails the low-gradient injection of colloidal silica in the soil pores, a stabilizer material which transforms into a firm gel after a well-controlled time. This gelation enhances the mechanical response of the soil skeleton - pore fluid system. The microscopic mechanism of improvement has not yet been established, a fact prohibiting the formulation of constitutive models. This study explores the possibility of using existing constitutive models for simulating the response of stabilized sands. A bounding surface plasticity model for sands (NTUA-SAND) is used herein for this purpose, after appropriate re-calibration on the basis of published element test results on stabilized sand. Then, the efficiency of this modeling approach is explored through comparison with results from dynamic centrifuge tests. © 2014 Taylor & Francis Group, London.