既有结构基于评估使用年限的目标可靠度研究

Research on Target Reliability of Existing Structures Based on Assessed Working Life

在比较JCCS概率模式规范与我国统一标准规定的结构构件允许失效概率及目标可靠指标的基础上,研究了既有结构基于评估使用年限的目标可靠度.以评估使用年限内的允许累积失效概率与原设计使用年限内的允许累积失效概率相等为原则,建立了根据评估使用年限确定目标可靠度的方法,并提出了抗力需求折减系数建议值.以允许年失效概率为依据,提出了危险构件的可靠度定义和既有结构构件的使用安全寿命准则.以某锈蚀钢筋混凝土梁的受弯承载力分析为例,研究了其使用安全寿命、全寿命期检测评定周期等.

Target reliability of existing structures based on the assessed working life were studied based on comparison of allowable failure probability of structural members and target reliability index between the JCCS probabilistic model code and unified standards in China.Based on the principle that the cumulative failure probability within the assessed working life was equal to the cumulative failure probability within the original design working life,the method to determine the target reliability based on the assessed working life was proposed,and the resistance demand discount coefficients were suggested.Based on the allowable failure probability per year,the reliability definition of the dangerous components and the criterion of service safety life of existing structural components were proposed.Taking the bending capacity analysis of a corroded reinforced concrete beam as an example,the service safety life,detection and evaluation period of the whole life cycle were studied.