VANE SHEAR TESTS ON THIXOTROPY OF TAIHU LAKE AND BAIMAHU LAKE DREDGED SLURRIES

The shear strength of Taihu lake and Baimahu lake dredged slurries are tested with miniature shear vane apparatus at different stewing times after remolded. The thixotropy of two kinds of dredged slurries is studied. Test result shows that a sharp thixotropic strength increase at the first time after remolded is recorded. Then the thixotropic strength still increases, but at a slower rate. The increase of the thixotropic strength at 448d tends to be stable. The thixotropic strength of Taihu lake dredged slurries is higher than that of Baimahu lake at the liquid limit. The variation trend of thixotropic strength ratio is similar with the thixotropic strength. The thixotropy of dredged slurries increases with decreasing water content. The thixotropic strength ratio of the two kinds of dredged slurries at the liquid limit is close to that of the London and Detroit dredged slurries. It is less than that of Beauharnois and Shellhave dredged slurries. It is greater than that of Horten dredged slurries. The thixotropic strength ratio of the others besides the Beauharnois dredged slurries keeps stable at 448d. The two kinds of dredged slurries are low sensitivity clays according to the definition of the clays sensitivity.