Comparative investigation on dynamic shear modulus and damping ratio of marine soils in different seas
摘要
To understand the variation characteristics of dynamic shear modulus G and damping ratio with the increasing depth H of marine soils, a series of resonant column tests are performed on silty clay with various depths taken from the three borehole profiles in Bohai Bay. The test results are compared with the strain-compatible dynamic shear modulus G and damping ratio of marine soils in different seas and terrestrial soils cited from the published literatures. A remarkable finding of this study is that, the Bohai Bay silty clay represents the strong nonlinear and hysteresis behavior with low shear modulus and high damping, the dynamic shear modulus G and damping ratio increase or decrease regularly with the increasing depth H. The maximum dynamic shear modulus Gmax of various marine soils increases regularly with the increasing depth H. The marine soils in different seas represent more nonlinearity, hysteresis and higher small-strain damping compared with those of the terrestrial soils at the same depth H, and the correlation between the dynamic shear modulus G and the depth H of marine soils is very significant, and the proposed prediction equations for the maximum dynamic shear modulus Gmax and dynamic shear modulus G based on depth H are quite universal for marine soils.