MODELING OF CYCLIC DEFORMATION AND STRENGTH CHARACTERISTICS OF SILICA TREATED SAND

摘要

A new chemical grouting method has been developed to prevent the liquefaction of sandy ground. The grouting material used in this study is a kind of colloidal silica. The sand gel treated by a colloidal silica shows better long-term stabilization than the usual silica grouting material such as sodium silicate or acid silica sol. In the present paper, in order to study the deformation and the strength characteristics of silica treated sand, monotonic and cyclic undrained torsional shear tests are performed. The soil specimens are prepared using a newly developed specimen preparation apparatus. The test results show that the deformation and strength characteristics are considerably improved by the colloidal silica treatment. Based on the test results, an elasto-plastic constitutive model for the treated sand is proposed and its applicability to liquefaction analysis is shown.