基于细观理论的粗粒土剪胀性及本构模型

Dilatancy of Coarse Aggregates and Its Modeling Based on Micro Theory

摘要:

基于能量守恒原理和Rowe提出的最小能比原理从细观角度建立了考虑颗粒破碎的剪胀方程,并对不同围压下颗粒破碎耗能因子在试验过程中的变化趋势进行了归一化.为了验证该剪胀方程的正确性，引入修正硬化准则，建立了相应的弹塑性本构模型，然后将该模型用于2种不同形状粗粒土室内大三轴试验的数值模拟，对比分析表明,该模型能够较好地描述粗粒土的剪胀特性和应力应变关系.

关键词:剪胀性; 颗粒破碎; 粗粒土; 细观理论; 本构模型

Abstract:

Based on principles of energy conservation and energy minimum ratio proposed by Rowe, the dilatancy equation considering particle breakage was established on micro level. In order to verify the correctness of dilatancy equation, the corresponding elastic plastic constitutive model was set up by introducing the modified hardening rule. Then the numerical simulation of triaxial tests about two different shape coarse granular aggregates was carried out. Results show that this model can accurately describe the dilatancy characteristic and stress strain relationship of coarse granular aggregates.

Key words:dilatancy; particle breakage; coarse granular aggregates; micro theory; constitutive model