Abstract: The system reliability analysis method of arch-bridge is presented based on the failure model of arch rib, which is the most important failure model of arch-bridge. The control sections of arch rib in the analysis of bearing capacity reliability are determined according to the "five-spot coincidence method", which is often used in arch-bridge design. The representative failure models of arch rib are searched and the rib section resistances are calculated by incremental method and disadvantage lo

Key words: masonry arch-bridge, bearing capacity, reliability, failure model, incremental method

摘要： 针对拱式桥结构体系中的主要受力构件。拱肋进行分析，借鉴拱桥设计中的“五点重合法”确定研究截面，并对 该截面进行不利布载。对每一种荷载布置型式，采用荷载增量法进行拱桥结构失效模式的寻找和截面抗力的计算。 给出其承载力可靠度功能函数，推导功能函数中结构抗力和作用效应概率模型，并利用改进的一次二阶矩法计算 圬工拱桥承载力可靠度指标评估值。最后给出实桥验证算例

关键词: 圬工拱桥, 承载力, 可靠度, 失效模式, 荷载增量法