The influence of the matric suction to the shear strength characteristic of residual soil weathered from mudstone of Binh Lieu formation in Quang Ninh region

Abstract

Shear strength is one of the basis parameters of unsaturated soils and plays an important role in soil slope stability. This paper researches on the shear strength characteristic of the residual soil weathered from mudstone of Binh Lieu formation in Quang Ninh region by the consolidated drained triaxial shearing test (CD) which uses the modified triaxial apparatus in the Geotechnical laboratory in Thuyloi University. The results show that angle of internal friction, ’, of the soil is nearly constant but the angel  decreases and the shear strength increases when the matric suction of the unsaturated soil increases.