氯盐侵蚀下钢筋混凝土结构锈胀开裂研究综述

氯盐侵蚀引起的钢筋锈蚀是引发钢筋混凝土结构锈胀开裂的主要原因.总结归纳了氯盐侵蚀下的钢筋锈蚀产物分布、钢筋锈蚀引起的作用在混凝土保护层上的锈胀力,以及由锈胀力作用造成的混凝土保护层表面开裂等3个方面的研究成果.在此基础上,针对当前研究中存在的问题提出了一些建议,指出将混凝土视为均质材料的简化模型并不能准确模拟钢筋锈蚀引起的混凝土保护层锈胀开裂行为,今后的研究应着重于建立混凝土的细观分析模型.自然环境下的钢筋锈蚀产物分布形态不唯一,二维模型与实际工程中的三维构件存在较大的差异;人工气候环境引起的钢筋非均匀锈蚀与自然锈蚀间的差异尚不明确,有待进一步研究.

State-of-Arts about the Chloride-Induced Steel Corrosion and Concrete Cover Cracking in Reinforced Concrete Structures

The chloride-induced corrosion of reinforcements has been identified as the main cause of cracking in reinforced concrete due to the expansion of corrosion products.The research achievement were summarized from three aspects including the chloride-induced steel corrosion build-up,corrosion-induced expansive force and concrete cover cracking.Some suggestions were put forward to provide a guide for the further research.It is pointed out that the simplified models that consider the concrete as a homogeneous material cannot accurately describe the concrete cover cracking process due to the chloride-induced steel corrosion,and future researches should focus on the establishment of a mesoscopic model of concrete.In addition,the corrosion product distribution model under natural conditions is not unique,and there is a big difference between the simulated 2D model and the actual 3D structural member.The difference between the non-uniform steel corrosion induced by artificial environment and natural corrosion is not clear,and further research work is still needed.