Abstract:

The electrical resistivity of various lime-soil samples are studied indoor with four electrode resistivity measurement, the effects of different factors such as lime-soil ratio, water content, water saturation, soil structure and particle size on lime-soil samples were revealed. Under different water contents (about 15 %, 20 %, 25 % and 30 %), soil were mixed with lime at different lime-soil ratios (about pure soil, 1:10, 1:15 and 1:30). With light compaction test, the traverse and vertical resistivity of mixed soil samples were measured and the relationships between resistivity and physical properties of mixed soil samples with different lime-soil ratios are studied too. The electrical resistivity of mixed soil samples drops greatly with 15 %-20 % water contents, increases with about 20 % water content; and the resistivity reduces as the water content increased continuously. The electrical resistivity of lime-mixed soil sample larger than electrical resistivity of pure soil with 15 % water content, but the resistivity of lime-mixed soil samples is smaller than pure soil samples with 30 % water content. The resistivity is more lower as the lime mixing amount is larger. The electrical resistivity at transverse section is larger than at vertical section. The electrical resistivity increases from 0 to 50 ?•m as the unconfined compression strength increases. When the electrical resistivity larger than 50 ?•m, the resistivity decreases as unconfined compression strength increases. The relationship between water saturation and dry density is negative exponent; the relationship between porosity and void ratio is exponent reverse to the dry density. The resistivity is sensitive to the water content.

Key words: electrical resistivity, electrode distance, compacted soil, sensitivity analysis