摘要
随着科技的进步和运输需求的增长,跨海悬索桥作为重要的交通枢纽,具有结构复杂、高柔度等主要特征,一旦发生损伤后果可能非常严重。高墩高塔作为其核心承重构件,长期暴露于复杂的海洋环境中,在全寿命周期内不可避免地面临多种自然灾害作用的威胁,工程风险不确定性极大。同时贝叶斯网络作为一种可以将变量的概率推理关系联系起来的图型模型,广泛应用于结构体系定量评估中。因此,针对跨海悬索桥研究现状及面临的环境问题,本研究提出一种基于贝叶斯网络的多灾害风险定量评估方法。首先分析灾害风险因子,针对结构和环境特点,选取地震、强风和洪水潮汐冲刷作为主要灾害作用,考虑结构体系中的关键构件或截面,根据弯矩曲率分析结果确定构件或截面的损伤级别范围;其次通过构件或截面与结构体系的从属关系及荷载场景模拟,建立贝叶斯网络模型,获得结构系统灾害风险概率;最终参考风险等级矩阵和桥梁运营可接受风险水平,对目标体系开展风险评估,并通过单一荷载下的对比结果对评估结果进行有效性验证。其中高墩高塔结构以在建伶仃洋大桥为例,风险评估结果为三级,在寿命运营期处于较安全状态,需制定必要的应急方案。研究结果表明,该方法可为同类型桥梁多灾害风险评估提供理论支持,对防灾减灾方案制订具有指导意义。
With the advancement of technology and increasing demand for transportation,the sea-crossing suspension bridges,as important transportation hubs,are characterized by complex structures and high flexibility.Any damage to these bridges can result in severe consequences.The high piers and pylons,serving as the bridge core load-bearing components,are constantly exposed to the complex marine environments.They are inevitably threatened by various natural hazards throughout their lifecycle,which lead to significant uncertainties in engineering risks.As a graphical model that connects probabilistic reasoning among variables,the Bayesian network is widely used in the structural system quantitative assessment.In view of the present research situation and environmental problems of sea-crossing suspension bridge,this study proposed a quantitative multi-hazard risk assessment method based on Bayesian network.First,the hazard factors were analyzed.The earthquakes,strong winds,and flood-induced tidal scouring were selected as the main hazards,considering the structural and environmental characteristics.The damage level range was determined based on the moment-curvature analysis result,considering the key components or sections of structure.Second,by establishing the hierarchical relation between components or sections and structural system,along with load scenario simulation,the Bayesian network model was constructed to obtain the hazarid risk probability of structural system.Finally,the target system risk assessment was carried out by reference to the risk level matrix and the acceptable risk level of bridge operation.The evaluation result validity was verified by the comparison result under a single load.As an example,the high piers and pylons of Lingdingyang Bridge,currently under construction,were evaluated.The result indicates the risk level 3,which suggests that the structure remains in a relatively safe state during its operational life,although necessary emergency plans should be developed.The result shows that the prop
作者
柳成荫
任立辰
刘汉勇
张春海
张志刚
LIU Cheng-yin;REN Li-chen;LIU Han-yong;ZHANG Chun-hai;ZHANG Zhi-gang(Shenzhen Key Laboratory of Intelligent Structure System in Civil Engineering,School of Civil and Environmental Engineering,Harbin Institute of Technology,Shenzhen,Guangdong 518055,China;Research Institute of Highway,Ministry of Transport,Beijing 100088,China;Hebei Provincial Yanqing-Chongli Expressway Administration Center,Zhangjiakou,Hebei 075000,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2024年第11期134-142,共9页
Journal of Highway and Transportation Research and Development
基金
国家自然科学基金项目(52378295)
广东省自然科学基金项目(2024A1515010296)
广东省土木工程智能韧性结构重点实验室项目(2023B1212010004)
延崇高速基础设施智能监测与预警技术研究项目(KT3-YC-201920)。
关键词
桥梁工程
多灾害风险
贝叶斯网络
跨海悬索桥
高墩高塔
风险评估
bridge engineering
multi-hazard risk
Bayesian network
sea-crossing suspension bridge
high pier and pylon
risk assessment
