台风浪-潮-流相关性对桥梁群桩基础波流力的影响  

INFLUENCE OF WAVE-SURGE-CURRENT CORRELATION ON WAVE AND CURRENT LOADS TO ELEVATED PILE CAP FOUNDATION OF BRIDGE UNDER TYPHOONS

作　　者：尚黛梦 魏凯[1] 钟茜 秦顺全 SHANG Dai-meng;WEI Kai;ZHONG Xi;QIN Shun-quan(Department of Bridge Engineering,Southwest Jiaotong University,Chengdu 610031,China;China Railway Major Bridge Reconnaissance&Design Institute Co.,Ltd.,Wuhan 430034,China)

机构地区：[1]西南交通大学土木工程学院桥梁工程系,成都610031 [2]中铁大桥勘测设计院有限公司,武汉430034

出　　处：《工程力学》2022年第S01期187-194,共8页Engineering Mechanics

基　　金：国家重点研发计划项目(2021YFB1600300);国家自然科学基金项目(51978578)。

摘　　要：台风是我国主要的灾害性天气系统之一,台风作用下桥址区会产生巨浪、强潮、急流,导致桥梁群桩基础承受巨大的波流力。极端环境下的海洋环境参数浪、潮、流会相互作用,而现有的设计规范中较少考虑浪-潮-流的相关性,从而导致设计的保守。为研究台风浪-潮-流相关性对桥梁群桩基础波流力的影响,该文基于SWAN+ADICIRC耦合模型获取49条台风作用下浪-潮-流数据,采用三维嵌套Frank Copula模型得到浪-潮-流三维联合分布,建立100年重现期环境等值面,并采用势流理论与莫里森方程进行波流力计算。对不考虑浪-潮-流相关性与考虑浪-潮-流相关性计算得到的波流力进行对比分析。研究表明:考虑浪-潮-流相关性比不考虑浪-潮-流相关性计算得到的群桩基础波流力减小17.40%;波流力与有效波高、谱峰周期和流速呈现明显的正相关性,而对潮位的变化并不敏感;在考虑了浪、潮、流相关性后,水平剪力和基底弯矩对应的环境参数组合不再一致。Typhoon is one of the main disastrous weather systems in China.Huge waves,strong surges and rapid currents will be generated under the action of typhoon in the bridge site area,which will cause the elevated pile cap foundation of bridges bear huge wave and current loads.In extreme environments,the environmental parameters of waves,surges and currents are dependent on each other.The correlation of wave-surge-current is less considered in the existing design standards,resulting in a conservative design.In order to study the influence of wave-surge-current correlation on the wave and current loads to the elevated pile cap foundation of the bridge under typhoons,this paper obtained the wave-surge-current data under the actions of 49 typhoons based on the SWAN+ADICIRC model,and used the three-dimensional nested Frank Copula model to obtain the three-dimensional joint distribution of the wave-surge-current,and established environmental contours with 100-year return period.The wave and current loads were calculated using the potential flow theory and Morrison equation.The wave and current loads calculated with and without considering the wave-surge-current correlation were analyzed and compared.The research shows that:the wave and current load calculated considering the wave-surge-current correlation is 17.40%lower than that without considering the correlation;the wave and current load has an obvious positive correlation with effective wave height,spectral wave period and current velocity,but is not sensitive to the change of surge;after considering the correlation of waves,surges and currents,the combination of environmental conditions corresponding to the base shear and the mudline moment is no longer consistent.

关 键 词：浪-潮-流相关性 台风 COPULA 联合概率 跨海桥梁 群桩基础 波流力 

分 类 号：U443.15[建筑科学—桥梁与隧道工程]