考虑抗力随时间变化的既有钢筋混凝土桥梁承载能力可靠度评估方法

针对既有钢筋混凝土桥梁的特点 ,讨论了结构抗力的衰减模型 ,并提出了根据已有抗力信息采用回归分析方法及最小二乘法确定或修正模型参数的方法 ;建立了以现时刻为分析时间起点的考虑抗力随时间变化的继续使用期内承载能力可靠度分析模型 ,并讨论其求解方法。应用所研究的方法对一座实际钢筋混凝土桥梁的承载能力可靠度进行了分析和评估 ,为该桥的维修加固决策提供了重要的依据

Reliability Assessment Method of Load-bearing Capacity for Existing Reinforced Concrete Bridges with Consideration of Time-dependent Resistance

An attenuation model for time-dependent structural resis-tance of existing reinforced concrete bridges is introduced, and a method for determining or modifying the model parameters with available resis-tance information using regression and least squares principles is detailed. Furthermore, a reliability model of load-bearing capacity in further service time with the present time as the starting point and solving techniques of the model are presented. Finally, the reliability of load-bearing capacity for an actual reinforced concrete bridge is assessed using the model presented in this paper, which provides important guidance for the mainte-nance decision of the bridge.