Abstract:

A series of triaxial tests of saturated remolded loess under dynamic loading in isotropic and anisotropic consolidation stress states on condition of drain and undrain are performed to analyse its dynamic characteristics and backbone curves. Based on the dynamic triaxial test results, the effect of accumulated plastic strain is considered; and then the applicability of modified model of Hardin-Drnevich to saturated remolded loess is discussed. The results show that the modified model of Hardin-Drnevich could simulate the backbone curve of saturated remolded loess well. After that, the influences of isotropic and anisotropic consolidation stress states, confining pressure of consolidation, wave form and drain or undrain on the backbone curve for saturated remolded loess are also discussed. The backbone curves are all upper shift under anisotropic consolidation with the increasing confining pressure of consolidation; and it is shown that the strength of samples is increased; the impact of wave form on backbone curve is little; the effect of drain condition on it is upper shift comparing with undrained condition and this indicates that the strength of samples is enhanced. The conclusions can be for referenced by engineering designers.

Key words: loess, backbone curve, modified model of Hardin-Drnevich, dynamic elastic modulus test