近海大气环境下的钢筋混凝土结构常年受到氯离子的侵蚀，结构的抗震性能在服役期内不断退化。为研究近海大气环境下钢筋混凝土曲线桥梁的地震损伤风险变化规律，本文基于既往研究结果，确定不同环境参数及锈蚀参数的概率分布类型，构建了基于概率的氯离子侵蚀效应下钢筋混凝土材料劣化模型。在OpenSEES平台中建立了近海大气环境下曲线桥梁的有限元模型，进而对桥梁构件和系统分别进行了时变地震易损性分析。结果表明：在相同强度的地震荷载下，随着服役时间的增长，桥墩各类损伤状态下的超越概率均有所增大，而支座发生损伤破坏的概率略有降低；随着设防烈度的提高，构件的易损性曲线趋向平缓，抗震能力不断提高；此外，桥梁系统发生损伤的概率高于构件的损伤概率，在进行桥梁结构的抗震性能评估时，需综合考虑构件与系统的易损性分析结果。

The reinforced concrete structures in offshore atmospheric environment are eroded by chloride ions all the year round, and the seismic performance of the structures deteriorates continuously during the service period. In order to study the change law of seismic damage risk of reinforced concrete curved Bridges in offshore atmospheric environment, based on previous research results, this paper determined the probability distribution types of different environmental parameters and corrosion parameters, and built a probability-based reinforced concrete material deterioration model under chloride ion erosion effect. The finite element model of curved bridge under offshore atmospheric environment is established on OpenSEES platform, and then the time-varying seismic vulnerability of bridge components and system is analyzed respectively. The results show that, under the same intensity of seismic load, with the increase of service time, the exceedance probability of pier under various damage conditions increases, while the probability of support damage decreases slightly. With the increase of fortification intensity, the vulnerability curve of components tends to be flat, and the seismic capacity is constantly improved. In addition, the damage probability of the bridge system is higher than that of the component, so the vulnerability analysis results of the component and the system should be considered comprehensively when the seismic performance evaluation of the bridge structure is carried out.

TU375? ??? ?

国家重点研发计划课题(2019YFC1509302）；陕西省重点研发计划课题(2021ZDLSF06-10)。