堆石料广义塑性模型研究  

Generalized plasticity model for rockfill materials

作　　者：卞士海 李国英[2,3] 魏匡民[2,3] 周健[1] 

机构地区：[1]同济大学地下建筑与工程系,上海200092 [2]南京水利科学研究院岩土工程研究所,江苏南京210024 [3]水利部土石坝破坏机理与防控技术重点试验室,江苏南京210024

出　　处：《岩土工程学报》2017年第6期996-1003,共8页Chinese Journal of Geotechnical Engineering

基　　金：水利部公益性行业专项经费项目(201501035);国家自然科学基金青年科学基金项目(51509163)

摘　　要：通过分析试验资料和以往研究成果,修正了堆石料不同围压下剪切过程峰值应力比表达式,论述了塑性模量对平均应力的依赖性。基于广义塑性理论框架,借鉴Lade-Duncan单屈服面模型中引入塑性功定义硬化规律的思路,对塑性模量进行了修正,提出了一种改进的广义塑性模型。为了验证改进方法的合理性,塑性模量改进方法被应用于刘恩龙模型,同时使用提出的修正广义塑性模型预测了另外两种堆石料试验。不同围压下模型的预测结果与试验结果吻合较好,表明修正的模型可以较好地预测堆石料的应力–应变特性。Based on the experimental results and previous studies, the stress ratio at the failure （Mf） under different confining pressures is modified, and the pressure dependency of plastic modulus is discussed. Considering the idea that the hardening rule of Lade-Duncan single yield surface model is defined by introducing plastic work to yield surface expression, the plastic modulus is modified using the plastic work within the framework of the generalized plasticity theory, and a modified P-Z model is proposed. To check the validity of the improved method, the modified approach is applied to the constitutive model by Liu et al., and the modified P-Z model is employed to simulate the other two triaxial tests on rockfill materials. Satisfactory agreement between the numerical and experimental results under different confining pressures confirms the capability of the modified model in improving the prediction of stress-strain behaviour of rockfill materials.

关 键 词：广义塑性模型 塑性功 塑性模量 三轴试验 模型验证 

分 类 号：TV641[水利工程—水利水电工程] TU441[建筑科学—岩土工程]