Experimental Study on Electrical Resistivity Characteristics of Saturated Sand Mixes with Bentonite Slurry

Abstract

Bentonite slurry is widely used in underground and geotechnical engineering because of its strong ability of wall protection. Slurry penetration, which is of great significance for the soil stability, is difficult to observe directly during the soil and slurry interaction. Slurry penetration would change the electrical resistivity of soil, which provides an indirect method to monitor the degree of slurry penetration. This paper aimed to investigate the electrical resistivity characteristics of soil-bentonite mixtures. Several test groups with different material components were carried out. The effects of some factors including water environment, CMC (carboxymethyl cellulose) contents, soil particle gradation, and electrode distance on the electrical resistivity of slurry-soil mixtures were studied and the relationship between soil electrical resistivity and slurry concentration was established. The results in this paper can provide references for the application of the electrical method on slurry penetration.

Keywords

• geotechnics
• tunneling
• bentonite slurry
• saturated sand
• electrical resistivity