基于碳化寿命准则的钢筋保护层厚度研究

Research on the thickness of steelcover based on carbonation life criterion

当前,因保护层厚度不足而损害质量安全的问题时有发生。为解决该问题,本文采用概率法对碳化寿命模型下保护层厚度与可靠度的关系进行分析,并对规范中保护层设计厚度是否足够进行计算。结果表明:提高保护层厚度,结构的耐久性将明显改善,并且如以碳化作为寿命预测标准进行计算,耐久年限为50 a情况下,室内干燥环境要满足可靠指标大于0,需保证构件保护层厚度不小于36.7 mm,因此得出规范规定的最低保护层厚度难以满足相应的耐久性寿命标准要求。

At present,the problems happen from time to time that the insufficient protective layer thickness will damage thequality safety.To solve this problem,the relationship between the thickness of the protective layer and the reliability under the carbonation life model is analyzed by using the probability method,and whether the design thickness of protective layer in the specification is sufficient is determined by calculation.The results show that the durability of the structure will be significantly improved by increasing the thickness of the protective layer.If carbonation is taken as the standard of life prediction,under the condition of the durability period is 50 years,it is necessary to ensure that the component protection layer is greater than 36.7 mm to meet the reliability index greater than 0 in indoor dry environment.It is concluded that the minimum protective layer thickness required by the code is difficult to meet the requirements of durability life standard.