混凝土材料破坏过程的二维离散元模拟  

Two-dimensional simulation of concrete material fracturing by discrete element method

作　　者：张正珺[1] 刘军[1,2] 胡文[3] 云斌[3] 赵长冰[3] 

机构地区：[1]河海大学安全与防灾工程研究所,南京210098 [2]岩土力学与堤坝工程教育部重点实验室,南京210098 [3]河海大学岩土工程科学研究所,南京210098

出　　处：《水力发电学报》2010年第5期22-27,共6页Journal of Hydroelectric Engineering

基　　金：973(2007CB714104)资助项目

摘　　要：采用数值方法研究混凝土材料的破坏过程。用颗粒流程序PFC2D对混凝土试件单轴压缩破坏全过程进行模拟。采用PFC2D颗粒流程序中接触本构模型,并选择平行粘结模型用以模拟混凝土材料的强度特征。分析了数值试验中的应力-应变曲线以及体积应变的变化规律,讨论了应力-应变曲线下降段以及两倍峰值应变时试件的破坏特征,详细分析了颗粒尺寸、颗粒数目等细观参数对模拟结果的影响,从而为确定数值模型合理的颗粒数目和尺寸提供依据。同时把数值模拟结果与试验结果进行对比分析。结果表明,基于离散元法的混凝土材料破坏模拟具有显著的优点,可以真实地模拟裂纹的生成、扩展以及破坏的全过程。To study the fracturing and fragmentation of concrete material,the code PFC2D is used to simulate the total fracturing history of concrete specimens under uniaxial compression.In the simulations,the contact models of discrete particles and the parallel-bond model of concrete strength are adopted.The developments of stress-strain relationship and bulk strain are analyzed in details,and the fracturing behaviors at the descending stage of stress-strain curve and the two times peak strain are discussed.The effects of size and number of particles on the simulated results are compared to find the suitable size and number of particles for a specimen,and a comparison of the simulations with the experimental results is presented.The results show the effectiveness and advantage of the discrete element method in modeling the formation and development of cracks and the whole process of fragmentation.

关 键 词：水工材料 破坏模拟 离散元法 混凝土材料 单轴抗压实验 

分 类 号：TV314[水利工程—水工结构工程]