Experimental studies on liquefaction behavior of silt in the Huanghe River delta

The silt of Huanghe is chosen as research object in this paper on the basis of physical geography and geological survey.The stress-strain relationship of the silt under dynamic loading is established by using the results of dynamic triaxial and resonance vibration tests.Meantime pore pressure response and liquefaction strength of the silt under the simulated earthquake action are analyzed.Then the standardization of failure and the model of pore pressure for the undisturbed silt are proposed.Through the analysis of the tested results,the following conclusions are drawn.First,the dynamic stress of the same strain for the silty sand,silt,silty clay,and clay are larger with the increasing clay content.Second,pore water pressure ratio for the silt is 0.68,and is 0.87 for the silty sand when liquefaction failure is occurred.Third,as to silty sand,the cyclic stress ratio must be increased if silt liquefaction is occurred.The tested results can provide the parameters and basis for the evaluating method of the silt failure under earthquakes,which suit to the saturated foundation land of the native area.