Strength property of high liquid limit soil under different moisture

The strength property of silt is very important for the design and construction of subgrade.Specimens were prepared at different initial dry density and water content.The strength tests,such as direct shear test,unconfined compressive strength test,and California bearing ratio(CBR)test,etc.,were carried out for the silt and cement stabilized silt.And the strength parameters of them were obtained under different water content or moisture.The results show that the strength was seriously influenced by initial dry density and water content.Cohesion was increased with water content first,but was decreased afterwards.When the silt was stabilized with 4% cement,the cohesion and friction angle were increased about 4 times and 2 times,respectively.The CBR of the unsoaking specimens were greater than that of the soaking one.But the CBR would reduce dramatically when the water content was over 20%,even if the samples were under unsoaking condition.So,the silt is a kind of special soils,which is very sensitive to water.