超固结黏土的剪胀方程及边界面模型  

Dilatancy equation and bounding surface model of over-consolidated clay

作　　者：徐斌[1,2] 陈柯好 庞锐[1,2] XU Bin;CHEN Ke-hao;PANG Rui(School of Hydraulic Engineering,Faculty of Infrastructure Engineering,Dalian University of Technology,Dalian,Liaoning 116024,China;State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian,Liaoning 116024,China)

机构地区：[1]大连理工大学建设工程学部水利工程学院,辽宁大连116024 [2]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024

出　　处：《岩土力学》2025年第2期449-456,466,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52379117,No.52279096,No.52279125)。

摘　　要：超固结黏土的应力-应变特性随超固结程度的演变呈现出较为复杂的力学特性。开发一个实用的本构模型可为超固结黏土的数值分析提供强有力的工具。首先,分析超固结黏土的剪胀特性随超固结程度的变化,将超固结参数引入剪胀关系中,建立形式简单的超固结黏土剪胀方程,并将其积分为塑性势面。然后,在边界面理论的框架下,结合所提出的剪胀方程,采用简单实用的理论方法,建立超固结黏土的边界面本构模型。最后,采用大范围超固结度下的三轴排水压缩和拉伸、三轴不排水压缩和拉伸试验以及复杂应力路径试验对所提本构模型的性能进行全面验证。结果表明:所提出的模型可以较好地描述超固结黏土的应力-应变特性随超固结程度的变化,并且在体变和孔压模拟方面具有较大的优势。The stress-strain characteristics of over-consolidated clay exhibit complex mechanical characteristics with the evolution of the degree of over-consolidation.Developing a practical constitutive model can provide powerful tools for the numerical analysis of over-consolidated clay.Initially,variation of the dilatancy behavior of over-consolidated clay with degree of over-consolidation is analyzed.By introducing the over-consolidation parameters into the dilatancy relation,a simplified dilatancy equation for over-consolidated clay is established.The dilatancy equation can be integrated as a plastic potential surface.Subsequently,a practical bounding surface model is developed within the framework of bounding surface theory,utilizing the proposed dilatancy equation through a straightforward theoretical approach.Finally,the performance of the model is comprehensively validated through triaxial drained compression and extension tests at multiple levels of over-consolidation,along with undrained triaxial compression and extension tests and complex stress path tests.The results indicate that the model effectively describes the stress-strain characteristics of over-consolidated clay with the degree of over-consolidation and exhibits significant advantages in simulating volumetric deformation and pore water pressure.

关 键 词：黏土 超固结 剪胀方程 边界面理论 临界状态 

分 类 号：TU43[建筑科学—岩土工程]