一个改进的筑坝粗粒料统一广义塑性模型  

A Modified Generalized Plasticity Model for Coarse-grained Dam Materials

作　　者：宁志远 王樱畯 徐建军 朱晟[2] NING Zhi-yuan;WANG Ying-jun;XU Jian-jun;ZHU Sheng(Power China Huadong Engineering Co.,Ltd.,Hangzhou 311122,Zhejiang Province,China;Hohai University,Nanjing 210098,Jiangsu Province,China)

机构地区：[1]中国电建集团华东勘测设计研究院有限公司,浙江杭州311122 [2]河海大学水利水电学院,江苏南京210098

出　　处：《中国农村水利水电》2023年第4期294-301,共8页China Rural Water and Hydropower

摘　　要：为准确预测抽水蓄能电站面板堆石坝长期运行变形性态,针对原筑坝粗粒料统一广义塑性本构模型无法较好模拟卸载、再加载过程中应力应变曲线的“滞回圈”现象,在卸载塑性模量中引入一个具有正值二阶导数的模量因子对原模型进行改进,可更好地描述模量随卸载进行而逐渐降低的特性。同时,通过引入应力比和塑性剪应变相关的模量函数,将原模型适用范围拓展至材料应力应变曲线的峰后软化阶段。基于室内三轴试验资料验证了模型有效性,结果表明,改进模型对粗粒料应力应变关系的表征精度更高,可反映如“滞回效应”“、棘轮效应”和应变软化现象。最后,推导并补充了参数β=1时的屈服面显式表达式,可用于抽蓄工程堆石坝长期服役性态预测的有限元数值分析。In order to accurately predict the long-term operation behaviour of concrete-faced rockfill dams of pumped-storage power sta⁃tions,the unified generalized plasticity constitutive model for coarse-grained dam materials is modified by introducing a modulus factor with a positive second derivative,which can improve the model’s behaviours in simulating the“hysteresis loop”during the unloading-reloading process and reflecting the modulus’s gradually decrease during unloading.Meanwhile,the model’s effective scope of application is extended to the post-peak softening stage through incorporating functions related to the stress ratio and the plastic shear strain.Based on the laboratory triaxial experimental data,the model’s effectiveness is validated.Results show that the modified model can better reflect the“hysteresis ef⁃fect”,“Ratchet effect”and softening of the coarse-grained materials.In addition,the explicit expressions of the yield surface under the mod⁃el parameterβequal to unity are supplemented,which can be used for finite element numerical analysis of long-term behaviour prediction of pumped-storage rockfill dams.

关 键 词：本构模型 筑坝材料 广义塑性 蓄泄循环 

分 类 号：TV42[水利工程—水工结构工程]