岩土力学2025，Vol.46Issue(9)：2816-2824,9.DOI:10.16285/j.rsm.2025.0251
考虑饱和度影响的结构性黄土弹塑性本构模型
Elastoplastic model of structural loess considering influence of saturation
摘要
Abstract
Due to its unique composition and fabric characteristics,loess exhibits structural and hydrological sensitivity,with its mechanical properties,including yield stress,shear strength,and deformation characteristics,being closely related to saturation and structural integrity.Considering the influence of saturation on the structural strength of loess,structural parameters such as yield stress,friction strength,and cohesion strength are introduced,and a functional relationship between these parameters and initial saturation was established.An evolution equation for structural parameters during plastic deformation was derived based on the structural degradation characteristics observed in shear deformation of loess.On this basis,the yield function for structural loess was developed by drawing inspiration from the Cambridge model.By taking yield stress and structural parameters as hardening parameters,an elastoplastic constitutive model for loess,accounting for saturation and structural evolution,was proposed using the associated flow rule,and the corresponding constitutive matrix was derived.Based on triaxial consolidation drainage test data for undisturbed Q3 loess from Dongjiahe Town,Tongchuan City,Shaanxi Province,stress-strain curves under varying confining pressures and saturations were predicted,and the model's rationality was verified.The results indicate that under low saturation conditions,loess exhibits high structural strength,which decreases significantly after yielding,accompanied by pronounced strain softening characteristics.As soil saturation increases,structural strength and corresponding yield stress decrease,with stress-strain curves becoming less steep,indicating increased plastic deformation and progressively less pronounced softening characteristics.The model effectively captures the relationship between loess structure and initial saturation,enabling a more accurate description of mechanical behavior under varying saturation conditions and reflecting how strain softening characteristics vary with saturation.关键词
非饱和黄土/初始饱和度/结构性/软化特性/弹塑性模型Key words
unsaturated loess/initial saturation/structural/softening characteristics/elastic-plastic model分类
建筑与水利引用本文复制引用
张淼,李林,郑瀚波,李盼盼..考虑饱和度影响的结构性黄土弹塑性本构模型[J].岩土力学,2025,46(9):2816-2824,9.基金项目
国家自然科学基金(No.52108297) （No.52108297）
中国博士后基金面上项目(No.2021M692742) （No.2021M692742）
中国博士后基金特别资助项目(No.2023T160560) （No.2023T160560）
陕西省秦创原引用高层次创新创业人才项目(No.QCYRCXM-2022-29) （No.QCYRCXM-2022-29）
中央高校基本科研业务费资助项目(No.300102212301,No.300102214303).This work was supported by the National Natural Science Foundation of China(52108297),the Postdoctoral Research Foundation of China(2021M692742),the Special Support Project of the China Postdoctoral Science Foundation(2023T160560),the Qin-Chuang-Yuan Imported High-level Innovation and Entrepreneurship Talent Project(OCYRCXM-2022-29)and the Fundamental Research Funds for the Central Universities(300102212301,300102214303). （No.300102212301,No.300102214303）
