模拟混凝土滞回行为的各向异性损伤模型  

AN ANISOTROPIC DAMAGE MODEL FOR SIMULATING THE HYSTERETIC BEHAVIOR OF CONCRETE UNDER CYCLIC LOADING

作　　者：龙渝川[1,2] 李正良[1,2] 

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045

出　　处：《工程力学》2011年第8期62-69,共8页Engineering Mechanics

基　　金：国家自然科学基金项目(50909109);教育部高等学校博士学科点科研基金项目(20090191120031);中央高校基本科研业务费资助项目(CDJRC10200005;CDJZR10200006)

摘　　要：该文引入相互独立的拉损伤、压损伤演化规律,分别描述受拉开裂和受压破碎导致的混凝土损伤行为,然后采用非线性卸载-线性重加载模拟滞回行为,建立了改进的各向异性损伤模型。该文还建议了模型关键参数的率定方法。应用该模型模拟混凝土受拉和拉-压往复加载试验,计算获得的应力-应变曲线与试验曲线具有良好的可比性,能够反映损伤导致的刚度退化、残余变形累积、加卸载滞回耗能行为以及微裂缝闭合引起的刚度恢复现象。算例结果表明,该模型适宜模拟往复加载下的混凝土非线性行为。A modified anisotropic damage model is developed by introducing two independent damage evolution rules to simulate the distinct behaviors of concrete due to tensile cracking and compressive crushing. Herein, the hysteretic behavior under cyclic loading is modeled using nonlinear unloading-linear reloading stress branches. The calibrating method of key parameters is also proposed. Subsequently, the model is used to analyze the response of concrete under cyclic tension and tensile-low compressive load. The stress-strain curves calculated by the model are highly comparable to those obtained by the tests and they reflect the damage-induced stiffness degradation, accumulation of residual deformation, hysteretic energy dissipation and stiffness recovery effect due to crack closing. The numerical results show that the modified damage model is applicable to simulating the nonlinear behavior of concrete under cyclic loading.

关 键 词：混凝土 连续介质损伤力学 各向异性损伤模型 滞回能量耗散 刚度恢复效应 参数率定 

分 类 号：TU313[建筑科学—结构工程]