EXPERIMENTAL RESEARCH ON PERMEABILITY CHARACTERISTICS OF UNSATURATED AND REMOULDED LATERITE IN NORTHERN SHAANXI PROVINCE

Influences of dry density and volumetric water content on permeability characteristics of unsaturated Baode Fm. laterite are studied by adopting Van Genuchten model on basis of measured results. The results show that with different dry density, unsaturated permeability coefficient is accelerated monotonically and increasing with increase of volumetric water content in semilogarithmic coordinates. Unsaturated permeability coefficient is approximate linear related to volumetric water content. The permeability coefficient of dense unsaturated laterite is relatively sensitive to change of volumetric water content. With different dry density, the unsaturated permeability coefficient has an exponential function relationship with the matric suction in semilogarithmic coordinates. The unsaturated permeability coefficient is monotonically decreasing with increase of matric suction. When dry density of soil is relatively high, the permeability coefficient of unsaturated laterite is changing more violently with change of matric suction. The permeability coefficient of dense unsaturated laterite is considerably sensitive to change of dry density.