SOIL-WATER CHARACTERISTIC CURVE OF LATERITIC CLAY IN WEST ZHEJIANG IN FULL SUCTION RANGE

In order to study soil-water characteristic curve(SWCC) of undisturbed lateritic clay in West Zhejiang in full suction range, three suction control or measurement methods are used, including the pressure plate method, filter paper method and saturated salt solution method to measure the water moisture under different suction. The results show that SWCC obtained from different methods can be coincidence with the same suction and SWCC in full range can be measured with the combination of three different methods. SWCC of undisturbed lateritic clay in full range show that the air entry values of clay is very low, only about 20kPa. Furthermore, compared with the typical SWCC of unsaturated clay, the transition section of SWCC of undisturbed lateritic clay is not a straight line but composed by two lines with different slopes, which is caused by the grain group aggregate between lateritic grain mass.