土的统一硬化模型

 土的统一硬化模型是基于剑桥模型，以变换应力方法和统一硬化参数为基本要素建立起来的弹塑性本构模型体系，它通过采用基于SMP准则、Lade准则或广义非线性强度理论的变换应力方法，实现了模型与强度准则的有机结合和模型的三维化。统一硬化参数的应用使模型可以描述土的剪缩、剪胀、硬化和软化、超固结性、各向异性、结构性、蠕变压缩和渐近状态等诸多特性。模型的参数较少、物理意义明确且可通过常规试验确定。它不仅发展和拓宽了剑桥模型的应用范围，而且也便于与现有工程软件结合，在工程中具有广阔的应用前景。

UNIFIED HARDENING MODEL FOR SOILS

Unified hardening(UH) model is an elastoplastic model system proposed based on the Cam-clay model，which includes two basic elements，namely，transformed stress method and unified hardening parameter. The model is combined with strength criteria by adopting the transformed stress methods on the basis of the SMP criterion，the Lade¢s criterion and the generalized nonlinear strength theory. The model，to which the unified hardening parameter is introduced，is able to describe many mechanical behaviors，including strain hardening and softening，stress dilatancy，over-consolidation，inherent anisotropy，structure，creep compression，asymptotic state and so on. Fewer parameters required in the model are determined by the conventional triaxial test. The model not only develops the Cam-clay model but also is easily exploited in the engineering software. Therefore，its application to engineering appears to be highly promising.