大气环境下混凝土中钢筋开始锈蚀条件的试验研究

一般大气环境下混凝土中钢筋锈蚀与混凝土碳化深度有密切关系。实际工程调查结果表明 ,不同环境下钢筋开始锈蚀与碳化深度之间的关系有很大差异 ,将一般大气环境分为室内环境、室外淋雨、室外不淋雨、环境相对湿度 5 0 %～ 70 %、70 %～ 90 %、90 %以上 6类 ,对各种环境下混凝土中钢筋开始锈蚀与混凝土碳化深度之间的相对关系进行了试验研究 ,给出了不同大气环境钢筋开始锈蚀时碳化深度的具体结果。

THE EXPERIMENTAL RESEARCH ON THE CONDITIONS FOR OCCURRENCE OF INITIAL CORROSION OF STEEL BAR WITHIN CONCRETE UNDER ATMOSPHERIC ENVIRONMENT

Steel corrosion has close relationship with carbonation depth in concrete under atmospheric environment. The investigation of the existing buildings reveals that the relationship between steel corrosion and carbonation depth is very different under different environment. In this paper,the atmospheric environment is classified as six types:indoors,outdoors exposed to rainfall,outdoors protected from rainfall,and the environment with relative humidity respectively of 50%～70%,70%～90%,and more than 90%. A experiment is carried on correlation between occurrence of initial corrosion of steel bar and carbonation depth under each environment,and the specific carbonation depths when steel starts to rust under different environment are supplied.