【摘要】 基于ABAQUS,以多龄期混凝土构件为研究对象,在数值建模方面,采用三维实体线性减缩单元C3D8R和两结点三维单元T3D2模拟混凝土材料、内嵌钢筋的力学行为,将指数衰减摩擦模型用于锈蚀钢筋与混凝土间接触问题上,并将Hsich-Ting-Chen四参数强度准则作为混凝土材料的破坏准则;在材料性能退化方面,基于修正斜压场理论,以锈蚀箍筋、纵筋、受压区锈胀开裂混凝土及核心区约束混凝土为对象,综合各既有材料退化模型,预测了材料退化后的力学性能,得到了开裂混凝土、锈蚀钢筋、混凝土及其之间黏结滑移的本构模型。进而,采用多龄期混凝土构件抗震性能试验研究结果,对提出的基于ABAQUS软件平台的锈蚀混凝土构件数值建模理论进行了可靠性验证,结果表明:所建立的数值建模理论可以有效地模拟锈蚀混凝土构件的抗震性能退化规律,为既有混凝土结构的数值建模理论提供了一种有效的研究方法。更多还原

【Abstract】 Based on finite element program ABAQUS,regarding RC multi-age components as research object,the unit C3D8 R and unit T3D2 were used to simulate the mechanical behavior of concrete and reinforcement,and the superiority of exponential damping friction model for handling with the problem of contact between corrosion reinforcement and concrete was obviously exhibited,then the Hsich-Ting-Chen strength criterion was taken as concrete failure criterion. The loss of the cross sectional area of reinforcement bars,reduction of the cover and core concrete strength were modified by the single-factor time-dependent corrosion rate. Considering the cracking and spalling in the compressed concrete of compression zone caused by reinforcement corrosion,the modified compressionfield( MCF) was used to predict the time-dependent compressed concrete strength. Finally the modified material constitutive models of corroded reinforcement,concrete and bond-slip were provided. Considering the data of multiage RC component under low frequency cyclic loading,numerical model theory for corroded RC component mentioned above was proved to be reliable,and the achievements can provide a feasible and effective numerical model for the existing RC structures.更多还原