摘要
采用颗粒流程序对混凝土循环加载试验进行离散元模拟,模拟结果显示:局部摩擦耗能的分布反映出损伤发生的薄弱区域;累积摩擦耗能与循环加载次数呈线性关系;摩擦耗能的累积速率对循环荷载大小敏感。基于摩擦耗能与疲劳损伤之间的相关性,提出了基于摩擦耗能的黏结退化模型,分析了模型参数与疲劳寿命之间的关系。对疲劳试验的模拟结果表明:该文提出的模型能够模拟出循环荷载下混凝土的疲劳寿命,以及变形演变、刚度退化、裂纹发展等疲劳损伤累积行为,可用于分析复杂荷载工况下的疲劳损伤累积规律。
Numerical tests of concrete subjected to cyclic loading were preformed using particle flow code software,and the simulation results show that:the distribution of local friction energy reflects the potential area of damage;the cumulative friction energy has a linear relationship with the number of loading cycles;the cumulative rate of friction energy is sensitive to the load level.Based on the correlation between friction energy and fatigue damage,a bond-degradation model based on cumulative friction energy is proposed,and the relationship between model parameters and fatigue life is analyzed.The simulation results of the fatigue test show that:the proposed model can simulate the fatigue life of concrete under cyclic loading,as well as the fatigue damage behavior such as deformation evolution,stiffness degradation and crack evolution.The model can be used to analyze the cumulative characteristics of concrete fatigue damage under complex load conditions.
作者
张培
任青文
ZHANG Pei;REN Qing-wen(College of Civil Engineering and Mechanics,Xiangtan University,Xiangtan 411105,China;Department of Engineering Mechanics,Hohai University,Nanjing 211000,China)
出处
《工程力学》
EI
CSCD
北大核心
2021年第S01期100-109,共10页
Engineering Mechanics
基金
国家自然科学基金项目(51739006)。
关键词
混凝土
循环荷载
颗粒流方法
疲劳损伤
黏结退化
concrete
cyclic loading
particle flow code
fatigue damage
bond degradation
