非饱和无粘性土动剪切模量的实用计算方法

A Useful Procedure for Estimating the Dynamic Shear Modulus of Partially Saturated Cohesionless Soils

提出可以考虑平均有效应力、孔隙比和颗粒特征对非饱和无粘性土最大剪切模量比及最优饱和度的综合影响的方法 ,仅需四个参数 :土的级配、孔隙比、平均有效应力和颗粒形状 ,因此可避免一系列复杂的动力试验 .提出的方法和Hardin公式、吴世明公式一起 ,共同提供了一个计算无粘性土 (干的、饱和的或非饱和的 )低幅剪切模量的合理途径 .而且此模量对土质及场地条件变化的敏感程度也可用本文方法加以确定 .

A method is proposed for predicting the combined effect of confining stress,void ratio,and particle characteristics on the maximum shear modulus ratio and optimum degree of saturation in partially saturated cohesionless soils.Only four soil parameters are needed,namely,gradation,void ratio,confining pressure,and grain shape.Thus,a series of complicated dynamic tests can be avoided.Hardin's Equation,Wu's Equation,and the method described herein for calculating the maximum shear modulus ratio and the optimum degree of saturation of partially saturated cohesionless soils together provide a complete approach for evaluating the low amplitude shear modulus of cohesionless soils in either a dry or partially saturated condition.Furthermore,the sensitivity of the modulus to variations in soil and site condition can be determined by means of this predictive technique.