水泥固化污染土电阻率试验研究

Experimental study on the electrical resistivity of contaminated soil-cement

通过低频交流电阻测试仪测定在室内制备的水泥固化污染土样的电阻率,采用电阻率法研究龄期、水泥掺入比、似水灰比及污染物含量对固化土电阻率的影响。结果表明,固化污染土的电阻率随着似水灰比和污染物含量的增加而减小,随着龄期和水泥掺入量的增加而增大,与无侧限抗压强度呈线性正相关。研究表明,可以通过固化土电阻率反映水泥固化土桩成桩质量和水泥固化土强度等指标。

This paper takes it as its purpose to introduce our investigation results of the influencing factors of the electrical resistivity of soil-cement by using the special device made by Southeast University. As is known, soil-cement is widely used in our country to consolidate the soft ground. The problem under concern is that though literature studies are now fruitful on the mechanical performance of the soil-cement, few articles are engaged in the study of the influencing factors of the electrical resistivity. So lots of samples of contaminated soil-cement are prepared in laboratory. We have also done experiments on the mutual relation between the electrical resistivity and the water-cement ratio used, curing time, admixture ratio of cement, contaminated content, unconfined compression strength. The testing results gained from our investigation show that the electrical resistivity of the soil-cement tends to increase with the increase of the admixture ratio of cement and curing time, whereas it tends to decrease with the increase of the water-cement ratio and contaminant content. The reason for the above results can be deduced mainly because the liquid substance in the void changes the whole electric conductivity of the soil and forms a special component in the soil with its electrical resistivity. It is also found that the electrical resistivity is closely related with the unconfined compression strength. Thus, it can be expected that the electrical resistivity method is likely to be widely used for checking/controlling the quality of soil-cement in practice.