ABSTRACT
With the accelerated urbanization process in China, the reuse of sites contaminated with heavy metals is receiving increasing attention. In this study, the technique of carbonation solidification using active MgO was applied to the stabilization of Zn2+-contaminated red clay in the Guilin region. Synchronous tests of unconfined compressive strength and electrical resistivity were conducted to investigate the solidification effect of the polluted soil using active MgO carbonation. The results showed that the unconfined compressive strength of the solidified soil increased with the increase in contamination concentration. However, it exhibited a decreasing trend with the increase in the content of active MgO. Moreover, the strength first increased and then decreased with the extension of carbonation time. The addition of active MgO resulted in strength enhancement ranging from 100% to 349.07%. It was observed that there exists a basic linear relationship between the unconfined compressive strength and electrical resistivity of the polluted soil under three different influencing factors. Furthermore, a set of equations for predicting the strength characteristics of polluted soil based on electrical resistivity was proposed. The use of electrical resistivity proves to be effective for evaluating the mechanical strength properties of heavy metal-contaminated soil.
