考虑非线性累积损伤的大跨多荷载桥梁的疲劳可靠度评估

发布时间：2018-08-06 09:06

【摘要】：针对大跨多荷载桥梁疲劳损伤累积非线性过程中的大量不确定性,对火车、汽车与风荷载作用下的大跨悬索桥,利用连续损伤模型提出了一个疲劳可靠度评估方法.首先,在连续损伤模型基础上,对模型参数进行分析;然后,根据工程应用的需要,适当简化疲劳模型,在连续损伤模型中引入合适的随机变量,定义疲劳可靠度分析的极限状态函数,假定多种未来可能的交通荷载和荷载增长模式,利用蒙特卡洛方法产生随机变量并计算失效概率;最后以香港青马大桥为例,讨论了该桥在不同荷载状况下使用120年后的疲劳失效概率.研究发现:若保持当前的交通状态,桥梁可保持良好状况,但未来交通荷载的快速增长会导致结构提前失效.
[Abstract]:Aiming at a large amount of uncertainty in the process of fatigue damage accumulation of long-span multi-load bridges, a fatigue reliability evaluation method is proposed for long-span suspension bridges under train, automobile and wind loads using a continuous damage model. Firstly, the parameters of the model are analyzed on the basis of the continuous damage model, and then, according to the need of engineering application, the fatigue model is simplified appropriately, and the appropriate random variables are introduced into the continuous damage model. The limit state function of fatigue reliability analysis is defined. The Monte Carlo method is used to generate random variables and calculate the failure probability on the assumption of a variety of possible future traffic loads and load growth models. Finally, the Qingma Bridge in Hong Kong is taken as an example. The fatigue failure probability of the bridge after 120 years under different loads is discussed. It is found that the bridge can maintain a good condition if the current traffic condition is maintained, but the rapid increase of traffic load in the future will lead to the early failure of the structure.
【作者单位】：厦门大学土木工程系;江苏省工程力学分析重点实验室;香港理工大学土木与结构工程系;
【基金】：国家自然科学基金资助项目(NSFC-51108395) 中央高校基本科研业务费专项资金资助项目(2012121032) 江苏省工程力学分析重点实验室开放课题基金资助项目
【分类号】：U441.4

【共引文献】