The shear strength of Ningming unsaturated expansive soil

A consolidated undrained triaxial compression test and a suction-controlled drained triaxial compression test on Ningming expansive soil are conduced using GDS unsaturated triaxial testing system.Total cohesive strengths under different states of matric suction,as well as a relation between suction strength and matric suction,are obtained from the tests.A shear strength formula of Ningming unsaturated expansive soil is put forward as result of regressing the testing result.Some results from unsaturated expansive soilsp triaxial tests in references are also satisfied with the formula.