Study on shear strength of compacted subgrade soils by test and numerical simulation

Three different plasticity index subgrade soils are selected from seasonal frozen soil region. Test specimens are made under the maximum degree of compaction with optimum moisture content. Static triaxial test is executed on the specimens under different confining pressures. The results show that with the same kind of soil, the shear strength increases with confining pressure; under the same confining pressure, shear strength increases with the plasticity index. The relationship between shear strength and confining pressure, plasticity index is obtained by means of multiple nonlinear fitting and shows a good correlation. Using ABAQUS finite element software for numerical simulation, Regularity for shear strength of different plasticity index subgrade soil has been basically the same rules with the experiment.