Estimating compression behavior of reconstituted clays with different initial water contents using two model parameters
Yiwen Zeng, Xiusong Shi, Zhen-Shun Hong
Abstract
The virgin compression line (VCL) of reconstituted clay relies on the initial water content, and various equations are proposed to describe this behavior. However, they might be case-specific and limited in capturing the full range of nonlinear VCL. Therefore, a compression model based on equivalent concept is proposed to estimate the VCLs of reconstituted clays with various initial water contents. This is done by incorporating a new equivalent concept into the natural compression law. The effect of initial water content is explicitly captured by an equivalent specific volume, and the progressive yielding during compression process is quantified by a novel state variable, which is formulated as a function of current specific volume. Only two compression parameters are required for the proposed model, and they can be readily calibrated by one conventional compression test. Verification reveals a satisfactory performance of our model in capturing the nonlinear compression behavior of reconstituted clays with a broad spectrum of initial water contents, liquid limits and stress levels. Besides, remolded yield stress of reconstituted clays can be well estimated based on the maximum curvature of the predicted VCL. The proposed equation could provide a rational reference for engineering design of preloading projects on soft foundation.