Experimental Study on Maximum Dynamic Shear Modulus of Yangtze River Floodplain Overconsolidated Soft Soil
To investigate the maximum dynamic shear modulus(Gmax)of overconsolidated soft soil from the Yangtze River floodplain,a series of bender element tests were conducted.These tests explored the effects of the overconsolidation ratio(HOCR),initial effective confining pressure(σ'3c),and void ratio(e)on Gmax.The results show that Gmax decreases as the void ratio(e)increases,given constant values of σ'3c and HOCR.Furthermore,increasing the HOCR reduces the decay rate of Gmax,while this decay rate remains relatively insensit-ive to changes in σ'3c.The void ratio-normalized maximum shear modulus,Gmax/F(e),was found to increase with rising stress-normal-ized initial effective confining pressure(σ'3c/Pa).However,the rate of increase exhibited a declining trend.Notably,Gmax/F(e)follows a unique power-law relationship with σ'3c/Pa,indicating a consistent pattern across different stress conditions.Through regression analysis,a predictive method for estimating Gmax in Yangtze River floodplain soft soils with varying overconsolidation states,initial stress condi-tions,and degrees of compaction has been developed.The accuracy and reliability of this method have been verified through independ-ent experimental testing,confirming its effectiveness in characterizing the dynamic shear properties of soft soils in this region.