非饱和花岗岩残积土的小应变剪切模量特性与其持水特征曲线确定方法  

Small-strain shear modulus properties of unsaturated granitic residual soils and determination method of soil-water retention curves

作　　者：尚召伟 孔令伟[1,2] 鄢俊彪 高志傲 王斐 黎澄生 SHANG Zhao-wei;KONG Ling-wei;YAN Jun-biao;GAO Zhi-ao;WANG Fei;LI Cheng-sheng(State Key Laboratory of Geomechanics and Geotechnical Engineering Safety,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China;University of Chinese Academy of Sciences,Beijing 100049,China;Department of Civil and Environmental Engineering,Shantou University,Shantou,Guangdong 515000,China)

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程安全全国重点实验室,湖北武汉430071 [2]中国科学院大学,北京100049 [3]汕头大学土木与环境工程系,广东汕头515000

出　　处：《岩土力学》2025年第4期1131-1140,共10页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.12272394)。

摘　　要：持水特征曲线是研究非饱和土强度、变形及渗流特性的基础,室内直接测量持水特征曲线复杂耗时。为快速准确获取花岗岩残积土的持水特征曲线,开展了不同含水率原状花岗岩残积土的共振柱试验,研究了非饱和花岗岩残积土的小应变剪切模量特性,并分别基于双应力状态变量最大剪切模量预测模型和单应力状态变量最大剪切模量预测模型反演了花岗岩残积土的持水特征曲线。研究表明:含水率对花岗岩残积土小应变剪切模量影响显著,剪切模量随着含水率的增大而减小,随围压的增大而增大;基于双应力状态变量最大剪切模量预测模型反演的持水特征曲线与压力板试验获得的结果较为一致,并通过试验数据检验了双应力状态变量最大剪切模量预测模型的准确性,讨论了模型的力学机制。利用共振柱试验不仅能够直接研究非饱和花岗岩残积土的小应变剪切模量特性,还可以通过反演法确定花岗岩残积土的持水特征曲线,为持水特征曲线的获取提供了一种新途径。The soil-water retention curve is the basis for the study of the strength,deformation and seepage characteristics of unsaturated soils,but the direct measurement of the curve in laboratory is complicated and time-consuming.In order to quickly and accurately obtain the soil-water retention curve of granite residual soil,the resonant column tests were carried out on granite residual soil with different water contents,the small-strain shear modulus characteristics of unsaturated granite residual soil were also studied.The soil-water retention curve of granite residual soil was inverted on the basis of the double-stress-variable maximum shear modulus prediction model and the single-stress-variable maximum shear modulus prediction model for unsaturated soils,respectively.The results show that the water content has a significant effect on the small-strain shear modulus of granite residual soil,and the shear modulus decreases with the increase of water content and increases with the increase of confining pressure.The inversion result of the soil-water retention curve based on the double-stress-variable maximum shear modulus prediction model is more consistent with the pressure plate experimental data.The accuracy of this prediction model is verified by the experimental data,and its mechanical mechanism is discussed.The resonant column test can not only directly study the small-strain shear modulus characteristics of unsaturated granite residual soil,but also project the soil-water retention curve of granite residual soil by the inversion method,which provides a new method for obtaining the soil-water retention curve.

关 键 词：原状花岗岩残积土 共振柱试验 小应变剪切模量 非饱和土 持水特征曲线 反演分析 

分 类 号：TU43[建筑科学—岩土工程]