氯盐环境混凝土结构服役寿命可靠度分析简化公式

Simplified formula for reliability analysis of concrete structure service life in chloride salt environment

考虑氯盐环境中氯离子侵入混凝土过程中的混凝土扩散系数、钢筋保护层厚度、临界氯离子浓度和表面氯离子浓度的随机性,建立了氯盐侵蚀下混凝土结构服役寿命的简化计算公式。简化公式比Monte Carlo抽样模拟方法和一次二阶矩验算点法更简便,无需迭代计算,且计算精度优于中心点法。由算例的计算结果可知,本文简化计算公式的计算精度满足实际工程中的精度要求,可以用于工程中氯盐混凝土结构的耐久性可靠度分析,具有较大的应用价值。

In this paper, the randomness of the diffusion coefficient of concrete, the thickness of steel bar protection layer, the concentration of chloride ion in the critical state and on the surface are considered in the process of chloride ion penetration into concrete in chloride salt environment, the simplified formula of concrete structure service life is established under chloride salt erosion environment. The simplified formula is more convenient than the Monte Carlo sampling simulation method and the first order second moment method, without iterative calculation, and the calculation precision is better than the central point method. The calculation results from the examples show that the accuracy of the simplified calculation formula are fully satisfied with the precision requirement in practical engineering, it can be used for durability reliability analysis of chloride concrete structure in engineering and has great application value.