摘要
为了分析桥梁伸缩缝在车辆冲击荷载作用下损坏的机理,对桥梁工程中常用的模数式伸缩缝建立了有限元模型,提出了其在车轮冲击荷载作用下的动力响应计算方法,以及非对称循环荷载作用下结构脉动强度的分析方法.对典型的RBM160型桥梁伸缩缝进行了动力强度计算与影响因素分析.结果表明:(1)伸缩缝中梁跨中、中梁支座焊缝位置是动应力最大的位置,计算结果与实际工程中常见的伸缩缝破坏位置一致;(2)水平与竖向轮载共同作用下结构的最大应力显著大于竖向轮载单独作用,说明水平轮载对伸缩缝损坏影响较大,但是国内外规范关于水平轮载的取值存在差别,由此获得的伸缩缝最大应力差别较大;(3)伸缩缝最大应力随着汽车车速的增大而增大,可以通过限制车速来控制模数式伸缩缝的最大应力,确保结构的安全性;(4)中梁与横梁之间的焊缝是伸缩缝结构的最薄弱部位,该部位的最大应力与焊缝饱满度有关,通过优化焊缝饱满度可以减小最大应力,提高结构安全性.
To analyze the damage mechanism of bridge expansion joint under the impact load of vehicles,a finite element model is established for the modular expansion joint commonly used in bridge engineering.The method for calculating the dynamic response under the impact load of the wheel as well as the analysis method of structural pulse strength under asymmetrical cyclic load are proposed.The dynamic strength of the typical RBM160bridge expansion joint is calculated,and the influencing factors are analyzed.The results show that:(1)The maximum dynamic stress lies at the middle of the center beam and the weld between the center beam and the transverse beam.Such calculation result is consistent with the common damage positions of the expansion joint in the actual projects;(2)The maximum stress of the structure under the combined effect of horizontal and vertical wheel loads is significantly greater than that of the vertical wheel load,indicating that the horizontal wheel load has a great influence on the damage of the expansion joint;however,there is a difference between the domestic and foreign specifications regarding the value of the horizontal wheel load,and the maximum stress of the expansion joint obtained from this difference is great;(3)The maximum stress of the expansion joint increases with the increase of the vehicle speed;as such,by limiting the vehicle speed,the maximum stress of the modular expansion joint can be controlled and the safety of the structure can be ensured;(4)The weld between the center beam and the transverse beam is the weakest part of the structure of the expansion joint,the maximum stress of this part is related to the fullness of the weld,and it can be reduced by optimizing the fullness of the weld to improve the structural safety.
作者
邹毓颖
吕俊平
丁勇
俞丹波
吕建华
ZOU Yu-ying;Lü Jun-ping;DING Yong;YU Dan-bo;Lü Jian-hua(Faculty of Architectural,Civil and Environmental Engineering,Ningbo University,Ningbo 315211,China;Zhejiang Linjin Expressway Co. Ltd.,Hangzhou 310000,China;Ningbo Roaby Technology Industrial Group Co. Ltd.,Ningbo 315800,China)
出处
《宁波大学学报（理工版）》
CAS
2019年第1期72-79,共8页
Journal of Ningbo University：Natural Science and Engineering Edition
基金
浙江省自然科学基金(LY19E080009)
浙江省交通运输厅科技计划项目(2015-2-47)
宁波市交通运输科技项目(201604)
宁波市科技服务业示范项目(2015F1008)
关键词
模数式桥梁伸缩缝
水平轮载
冲击荷载
有限元
动力强度分析
modular bridge expansion joint
horizontal wheel load
impact load
finite element
dynamicstrength analysis
