洪水作用下石拱桥结构动力响应的多相流瞬态分析OA

To address the need for assessing flood resistance reliability of ancient masonry arch bridges,the multi-arch Lugou Bridge was taken as a representative case,the volume of fluid(VOF)multiphase flow nu-merical simulation method was employed to analyze the bridge's structural dynamic response to flood impact,evaluating the disaster resistance of the masonry arch bridge.Results indicate that flood flows exceeding 10 000 m³/s severely impact the river embankments upstream and downstream of Lugou Bridge.When floodwater just submerges the bridge deck(discharge 15 948 m³/s),the bridge structure is subjected to a lateral force exceed-ing 100 MN,while the vertical force generated by flood counteract about 51%of the self-weight of the bridge,which critically compromises anti-overturning stability of the structure and results in the maximum global insta-bility risk.Moreover,under all flood scenarios,the risk of localised damage is relatively high at the bottom of upstream cutwater,the top of the downstream spandrel wall,and the connection between the arch ring and streamlined piers on the downstream side.The research promotes the fluid-structure interaction methodology for flood-induced dynamic response analysis of masonry arch bridges,and provides quantitative references for flood resilience and preventive conservation of masonry arch bridges.