基于非均匀锈蚀的钢筋力学性能及其与混凝土粘结性能研究

With the development of the civilization, the durability of reinforced concrete (RC) becomes more and more important. This program mainly focuses on the irregular spacial distribution of the corrosion and the influence of corrosion on the mechanical properties of the steel reinforcement and the bond performance of the RC structures. The μCT, video microscope, SEM/EDS and the bond test will be conducted to the RC specimens. The interfacial defect induced by the diameter of the steel reinforcement, the rib morphology, and the depth beneath the steel reinforcement will be investigated, and the influence on the corrosion propagation and corrosion properties, including the corrosion morphology, corrosion degree and corrosion zone, will be studied. The relationships between the defect and the corrosion morphology and the corrosion cracks will be investigated. The influence of corrosion on the bond will also studied according to the micro and macro tests. 3D scanning test will be involved to the corrosion steel reinforcement, the numerical model will be set up, and the bond prediction model will be proposed based on the corrosion properties and the corrosion cracks. The research of this project will be of great help for the RC design and life-cycle prediction.

随着城市化进程的加速，钢筋混凝土结构的耐久性问题日益突出。本项目针对当前锈蚀在三维空间不均匀分布及其对钢筋力学性能和混凝土粘结性能的影响中存在的问题，以钢筋混凝土结构为研究对象，通过X射线微观断层扫描（μCT）、光学显微镜、电镜以及梁式拉拔等试验，系统研究由变形钢筋外形特征、直径及钢筋下方混凝土高度等因素导致的钢筋混凝土界面过渡区缺陷对钢筋锈蚀的产生和发展规律，以及与钢筋锈蚀形态、锈蚀率、锈蚀域等钢筋锈蚀特性的关系，明确非均匀锈蚀特性对钢筋力学性能的影响，通过微观界面观测和宏观力学试验揭示钢筋锈蚀特性和锈蚀裂缝对粘结性能的损伤机理和劣化规律，通过锈蚀钢筋三维（3D）扫描结果研究钢筋锈蚀不均匀分布特性，基于非均匀锈蚀特性建立锈蚀钢筋力学模型，并根据钢筋锈蚀特性和锈蚀裂缝，研究锈蚀钢筋混凝土结构粘结性能影响规律，为氯盐环境下混凝土结构设计及全寿命预测提供理论依据与试验支持。

在“海洋强国”、“一带一路”以及“交通强国”等国家战略的背景下，近海钢筋混凝土结构的耐久性问题日益突出。本项目本项目针对钢筋的非均匀锈蚀行为及其对混凝土粘结性能的影响规律进行深入研究。研究以钢筋混凝土结构为对象，通过X射线微观断层扫描（μCT）、光学显微镜、电镜以及梁式拉拔等试验，系统研究各因素对钢筋锈蚀的产生和发展规律的影响，明确非均匀锈蚀特性对钢筋力学性能的影响，通过试验揭示钢筋锈蚀特性和锈蚀裂缝对粘结性能的损伤机理和劣化规律，通过锈蚀钢筋三维扫描结果研究钢筋锈蚀不均匀分布特性，建立锈蚀钢筋力学模型，并根据钢筋锈蚀特性和锈蚀裂缝，研究锈蚀钢筋混凝土结构粘结性能影响规律，为氯盐环境下混凝土结构设计及全寿命预测提供理论依据与试验支持。