Influence study of confining pressure on the dynamic parameters of the silty clay

The dynamic parameters of silty clay in Dujiangyan under dynamic loading are studied with RCA resonant column apparatus made in GDS Company of British with different confining pressures. The results show that: The test process can be reproducible; the maximum dynamic shear modulus and damping ratio are increasing, and the shear strain amplitude is decreasing with increasing confining pressures. The empirical formula of the dynamic parameters of silty clay in Dujiangyan vs. confining pressures is formed. The study can provide basic data for seismic dynamic response analysis of soil.