In-situ test on shear strength of expansive soil in Nanyang area, Henan Province

The determination of shear strength for expensive soil is always an important research object in this field. The shear strength is of much significance in the design of road foundation and slope in the expensive soil area. Taking the expensive soil in Nanyang Area, Henan Province, as study case, the in-situ shear test method, including preparing samples and test method, is proposed in the paper. The improved formula of calculating shear strength of expensive soil is suggested based on test data, and employed to determine the parameters. The results of landslides stabilities indicate that the method suggested is rationale.