Study of electrical resistivity and strength characteristics of zinc contaminated soil solidified by cement

The standard sand and ordinary Portland cement were selected as the experimental materials to prepare the samples of zinc contaminated soil solidified by cement. A series of tests was conducted to determine the unconfined compressive strength and electrical resistivity of the prepared samples. From these experiments, the effect of the current frequency on the electrical resistivity is investigated, and the influence of zinc ion concentration and curing time is also discussed on the delayed coagulation of cement, the electrical resistivity, unconfined compressive strength, the electrical resistivity and unconfined compressive strength. The results show that the electrical resistivity decreases significantly with the increase of current frequency, especially when current frequency is lower than 50 kHz. With the delayed coagulation influence of zinc ion content on cemented soil, the strength always grows slowly with the increase of zinc ion content but when the zinc ion content is up to 500 mg/kg, the delayed coagulation is abnormal. Both the electrical resistivity and strength increase with the increase of curing time, and fluctuate with the increase of zinc ion content. The electrical resistivity reaches a minimum and a maximum respectively at the zinc ion contents of 50 mg/kg and 500 mg/kg, and strength reaches a minimum and a maximum respectively at the zinc ion content of 100 mg/kg and 500 mg/kg. There exists a good linear relationship between electrical resistivity and unconfined compressive strength in different curing times.