Factors affecting shear modulus degradation of cement treated clay

Cement stabilization is often used to improve the bearing capacity and compressibility of soft clays. The present paper aims to investigate the shear modulus degradation of cement treated clay during cyclic loading. A series of cyclic triaxial test was conducted on artificially cement treated marine clay to study the factors affecting the shear modulus degradation. The parameters considered for the study are cement content (2.5-7.5%), curing days (7-28), cyclic shear strain amplitude (0.3-1%), number of loading cycles (1-100) and loading frequency (0.1-0.5 Hz). As in the case of natural clays, cement treated clays exhibit stiffness degradation which depends on mix ratio, curing days and loading conditions. The results show that the shear modulus degradation decreases with increase in the shear strain amplitude, cement content and curing days. It is also noted that irrespective of the mix ratio and curing conditions, the degradation decreases with increase in loading frequency. An empirical relationship is proposed to predict the shear modulus degradation based on Idriss's degradation model. The performance of the proposed empirical model is validated with the present experimental results. (C) 2014 Elsevier Ltd. All rights reserved.