Zhu Wenjun, Yu Kequan, Xu Yude, Zhnag Kai, Cai Xiaopei
Shanghai Key Laboratory of Rail Infrastructure Durability and System Safety, College of Transportation Engineering, Tongji University, Shanghai 201804, China.
Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI 48109, USA.
Materials (Basel). 2020 Feb 12;13(4):830. doi: 10.3390/ma13040830.
This paper investigates the influence of non-uniform corrosion in the transversal direction of the steel reinforcement on the cracking propagation of the concrete cover. An analytical model is proposed for the prediction of the corrosion-induced cracking performance. Both the thick cylinder theory of the concrete and the effect of transversal non-uniform corrosion of the steel reinforcement are involved by considering the corrosion layer of the corrosion products and a layer of concrete with the corrosion products filled with the pores. A three-stage corrosion-induced cracking of the concrete is proposed: corrosion without expansive stress to the concrete, corrosion with expansive stress to the adjacent concrete, as well as the corrosion-induced cracking of the concrete. By considering the non-uniform corrosion of the steel reinforcement and the tensile stress induced by the volumetric expansion of the corrosion products, the cracking initiation resulting from the non-uniform corrosion was involved in the prediction model. The models were also validated by the experimental results from both the corroded specimens and the existing literature, which would be helpful for the evaluation of the existing reinforced concrete constructions in the marine environment.
本文研究了钢筋横向不均匀锈蚀对混凝土保护层裂缝扩展的影响。提出了一个用于预测锈蚀诱导开裂性能的分析模型。通过考虑锈蚀产物的锈蚀层以及充满孔隙的锈蚀产物的一层混凝土，既涉及了混凝土的厚壁圆筒理论，又考虑了钢筋横向不均匀锈蚀的影响。提出了混凝土锈蚀诱导开裂的三个阶段：对混凝土无膨胀应力的锈蚀、对相邻混凝土有膨胀应力的锈蚀以及混凝土的锈蚀诱导开裂。通过考虑钢筋的不均匀锈蚀以及锈蚀产物体积膨胀引起的拉应力，预测模型中纳入了由不均匀锈蚀导致的开裂起始。这些模型还通过锈蚀试件和现有文献的实验结果进行了验证，这将有助于评估海洋环境中现有钢筋混凝土结构。
