氯盐环境下混凝土结构的耐久性设计方法

为了建立氯盐腐蚀环境下混凝土结构的耐久性设计方法,根据混凝土结构性能劣化的特点,在分析结构耐久性失效状态、可靠度设置水平、环境荷载及抗力影响因素的基础上,建立了钢筋初锈、保护层锈胀开裂及锈胀损伤达到最大限值这3种情况下的耐久性极限状态方程.基于结构可靠度设计理论,引入荷载和抗力变量的分项系数来反映结构耐久目标可靠指标的要求,建立了结构耐久性设计的分项系数表达形式.按照概率设计与分项系数设计具有相同可靠度水平的原则,给出了抗力分项系数的确定方法及不同耐久性极限状态下抗力分项系数的取值.

Durability Design Method of Concrete Structures under Chloride Environment

According to the characteristics of the structure performance degradation, after analyzing such factors as the structural durability failure state, reliability level, environmental load and resistance, the durability limit state equation considering steel corrosion initiation, concrete cover cracking and maximum corrosion induced damage value is established for the durability design under chloride environment. Based on the design theory of reliability, the partial coefficients of load and resistance are introduced to reflect the target reliability requirements of structural durability, and subsequently the partial coefficient expression form of structural durability design is established. According to the principle of the same reliability level for probability design and partial coefficient design, the determination method of partial coefficient for resistance and their values under different durability limit states are presented.