Effect of consolidation time on shear modulus of crushable volcanic soils

This paper aims to investigate the effect of consolidation time on the shear modulus of volcanic coarse-grained soils with different degrees of particle breakage. A series of bender element and cyclic triaxial tests was performed on volcanic coarse-grained soils under isotropic consolidation at different consolidation times. The simplified cyclic triaxial test has been proposed in order to clarify the effect of consolidation time on shear modulus. A good agreement among test results obtained from the simplified cyclic triaxial test, conventional cyclic triaxial test and bender element test can be observed. The test results also show that the rates of increase in the shear modulus due to consolidation for volcanic coarse-grained soils depend strongly on the degrees of particle breakage. In addition, empirical equations for predicting the time-dependent behavior of the shear modulus were also proposed based on the test results.