Research on Strength and Microstructure Characteristics of Cement Solidified Cadmium Contaminated Expansive Soil

Abstract

Depending on the laboratory test of consolidation expansive soil polluted by heavy metal Cd, we can use cement to cure expansive soil artificially polluted by cadmium nitrate in different concentration. The paper discussed how the heavy metal concentration, cement dosage and curing age influence the unconfined compressive strength by solidified expansive soil polluted by heavy metal and micro-structure properties were tested. The study results show that, as the curing age and cement concentration increases, the unconfined compressive strength increases; as the concentration of heavy metal increases, the unconfined compressive strength decreases; the effect of heavy metal concentration on strength is different, the effect of high concentration on strength is greater than the effect of low concentration; Through the change rules of the micro-structure characteristics, the results on micro-structure analyzing show that the reason of strength increases is the porosity decreases after adding cement.