【摘要】 在评估混凝土结构耐久性时,其关键是确定钢筋开始锈蚀条件.一般大气环境下混凝土中钢筋开始锈蚀的条件是混凝土碳化及钢筋脱钝.碳化残量是描述钢筋开始锈蚀的重要参数,其大小取决于部分碳化区长度、碳化速度及脱钝速度.以实际工程检测数据为主要依据,考虑不同环境条件,以碳化系数、保护层厚度和局部环境系数为主要参数,利用回归分析方法建立了碳化残量的计算公式,并由此计算钢筋开始锈蚀的时间.通过实际工程数据验证,表明本文给出的钢筋开始锈蚀时间计算方法,在工程应用上是可行的,从而为合理评定混凝土结构耐久性提供依据.更多还原

【Abstract】 Establishing the initial time of steel-bar corrosion is the key to the durability assessment of reinforced concrete structure.For reinforced concrete structure exposing to atmosphere,concrete carbonation and steel-bar depassivation are the conditions of steel-bar corrosion.Carbonation remains to be an important parameter describing the initial time of steel-bar corrosion and determined by length of incomplete carbonation zone,rate of carbonation and rate of depassivation.Based on spot-date,the calculation formula for carbonation remain is given in this paper,and is expressed by the major parameters including coefficient of concrete carbonation,cover depth and coefficient of local environment.By verifying the practical engineering,the method for calculating the initial corrosion time of steel-bar is available for durability assessment of reinforced concrete structure.更多还原