土的基本特性及本构关系与强度理论是土力学及岩土工程学科的重要理论基础之一。本文针对饱和黏土、砂土及堆石料等粗粒土,总结了这三类土在基本力学特性及本构强度理论方面的研究现状和发展趋势。饱和黏土部分主要包括压缩特性、剪切特性一临界状态及剪胀/剪缩、结构性及其破坏、中主应力影响、各向异性及主应力偏转效应、不排水抗剪强度、流变特性、微观力学解析模型等;砂土部分包括临界状态概念与剪胀性、砂土各向异性、应变局部化等;堆石料等粗粒土部分则以颗粒破碎对堆石料等粗粒土的力学性质的影响为主线,重点介绍了颗粒破碎的度量方法、颗粒破碎对剪胀性、临界状态线的影响以及相应的本构模型、宏观一微观的力学分析方法。
The elementary mechanical behaviors, constitutive modeling and failure criterion of soils from an important theoretical basis for the discipline of soil mechanics and geotechnical engineering. This paper focuses on the mechanical behaviors of saturated clay, sand and rockfill materials (coarse granular aggregates ) and a review for the recent development of constitutive modeling and failure criterion of these three types of the soils is presented. Some typical mechanical behaviors of saturated clay including compression behavior, shear behavior--critical state and dilatancy, behaviour of natural clay with loss of structure, influence of second principal stress, induced anisotropy and effect of principal stress rotation, undrained shear strength, time-dependency, and micromechanics-based analytical modeling are introduced first. Then, several important issues regarding the mechanical properties of sand are discussed, which involve the critical state framework and state-dependent dilatancy, anisotripic sand behaviour, strain localization and shear bending. Finally the researches on the influences of particle crushing on the mechanical behavior of rockfill materials (coarse granular aggregates) are particularly concerned. Attention is given to descriptive methods for particle crushing, the impact of breakage on the dilatancy, critical state line and stress-strain relationship, and macro-micro mechanical modeling.