钢筋混凝土结构裂缝损伤状态模型建模方法与分析

摘要

提出了一种钢筋混凝土（RC）结构裂缝损伤状态模型的有限元建模方法.基于弥散裂缝数值模型,采用ANSYS中APDL实体建模技术,通过调控单元应力应变关系矩阵来模拟裂缝开裂后的力学行为,建立钢筋混凝土结构在含有稳定裂缝损伤情况下的状态模型.作为数值算例,分析了钢筋混凝土简支梁在不同开裂状态、不同开裂位置和多种阻尼工况下的静动力特性.结果表明,混凝土首次开裂对结构静动力特性影响最大,已有裂缝的张开闭合对结构的影响较小.简支梁的不利开裂位置集中在荷载响应较大的支座和跨中附近,以支座处最为不利.阻尼削弱钢筋混凝土梁的动态响应,对结构影响机理复杂,非线性明显.上述分析验证了该裂缝损伤状态模型建模方法的合理性和有效性.%A finite element modeling method of state model for reinforced concrete（RC） structure with crack damages is proposed.The crack damage state model is established through adjusting the stress-strain matrix of element to simulate the mechanical properties of existent crack based on the smeared crack model and APDL solid modeling of ANSYS.As an example,static and dynamic analyses of a RC simply-supported beam with crack damage are performed by finite element analysis,and the situations of several cracking states,different crack positions and some damp conditions are discussed.The experimental results indicate that the foremost cracking of concrete has the most significant impact on the static and dynamic characteristics of RC structures,and the influence of crack opening and closing under stable condition is mild.The most unfavorable crack positions are nearby the support and mid-span with support is worse.The damps weaken the dynamic response of RC structures,and the effect is complicated and high nonlinear.According to the above analyses,this method is reasonable and feasible.