【摘要】 构件的抗力概率模型是进行桥梁结构时变可靠性研究的基础之一。既有钢筋混凝土桥梁材料的老化与损伤情况复杂使其抗力同时具有随机性、模糊性和时变性是一个模糊随机过程。在分析影响既有钢筋混凝土桥梁构件抗力不确定性因素的基础上,考虑桥梁在服役过程中的耐久性损伤对构件抗力的影响,在常规方法只能考虑抗力随机时变性基础上,进一步考虑模糊性,结合实测数据和现有资料建立了既有钢筋混凝土桥梁中混凝土强度、钢筋截面积和钢筋强度模糊随机时变模型,进而研究了在不修复情况下桥梁构件抗力模糊时变概率模型,分析了抗力平均值和标准差随时间和阈值变化的规律,并以受弯构件为例给出了具体分析过程和结果。更多还原

【Abstract】 The resistance probability model is the foundation for study on time-dependent reliability of bridge. Material aging and damage of existing reinforced concrete bridges are very complex processes which make the resistance random, fuzzy and time-variant, therefore the resistance development is a fuzzy stochastic process. Some uncertain factors influencing resistance are analyzed in this paper. Fuzzy random time-varying probability models for concrete strength, reinforcement strength and reinforcement cross section area considering durability damage in service life of existing reinforced concrete bridges are created based on measured data and other information. Fuzzy random time-varying probability model of the resistance of bridge members without maintenance is deduced. The variations of mean value and standard deviation with time and the threshold value are presented. Detailed analytic process and results are introduced using a bending member as an example.更多还原