Effects of contaminated soil on electrical resistivity and strength of cemented soil

To disclose the influencing rule of contaminated soil on cemented soil, the electrical resistivity method is used to describe the unconfined compressive strength and pollution characteristics. The study samples are cemented soils made of three different solutions (tap water, domestic sewage and paper mill effluent), silty clay and two types of cements (ordinary Portland cement, slag Portland cement). First, the influences of three different solutions on the liquid and plastic limit indexes of soil were compared and analyzed. Second, the changing laws of compressive strength and electrical resistivity of cemented soil, with different ages, cement types and contaminated soils, were studied and discussed. Finally, the quantitative relationship between electrical resistivity of cemented soil and its compressive strength was established. The results show that, the liquid and plastic limit indexes of soil may increase after contamination, whereas the plasticity index may decrease after contamination. The compressive strength and electrical resistivity of cemented soil may increase logarithmically with the age, and may be reduced after contamination. With the same age, however, the compressive strength and electrical resistivity of slag Portland cemented soil are generally higher than those of the ordinary Portland cemented soil, indicating that slag cement has good resistance to degradation. For soils with different contamination or different age, the compressive strength of both ordinary Portland cemented soil and slag Portland cemented soil increase linearly with the increase of electrical resistivity. Compared with the slag Portland cemented soil, the electrical resistivity is more sensitive to the ordinary Portland cemented soil. ©, 2015, Editorial Office of China Civil Engineering Journal. All right reserved.