Experimental Study on Influence of Dry Density on Soil-water Characteristic Curve of Hefei Expansive Soil

Abstract

The soil-water characteristic curve is an important curve in the study of unsaturated soil mechanics. It plays an important role in improving theoretical analysis and numerical calculation in geotechnical engineering to find out the effect of initial dry density on SWCC. Based on the filter paper test, four soil-water characteristic curves of Hefei remolded expansive soil samples under different initial dry densities were determined. The influence of initial dry density on SWCC was systematically analyzed. The results show that: (1) In the w-s curve, the suction will increase with the decrease of moisture content, and SWCC will move to the upper right with the decrease of dry density. (2) In the ω-s curve, the influence of the dry density on SWCC decreases as the suction becomes larger. When the moisture content is less than 10%, the difference in dry density no longer affects the SWCC. (3) Part of the SWCC with moisture content below 10% can be measured only once, which has important guiding significance for improving the efficiency of SWCC test. (4) In the Sr-s curve, the suction will increases with the decrease of the saturation, and the increase of the dry density of the sample causes the move of SWCC to the upper right.