上承式拱桥新型加固改造方法及试验验证  

A new reinforcement and reconstruction method and experimental verification for deck arch bridge

作　　者：谢肖礼[1] 李院腾 庞木林 XIE Xiaoli;LI Yuanteng;PANG Mulin(College of Civil Engineering and Architecture,Guangxi University,Nanning,Guangxi 530004,China)

机构地区：[1]广西大学土木建筑工程学院,广西南宁530004

出　　处：《石河子大学学报（自然科学版）》2023年第1期57-64,共8页Journal of Shihezi University(Natural Science)

基　　金：广西科技计划(桂科AB18126047)。

摘　　要：早期的上承式拱桥受限于设计荷载等级偏低、维护养护不到位和已运营多年等,其力学性能已不能满足现代交通需求,针对这一问题本文提出了一种新型的加固改造方法,即在拱肋与主梁间增设V杆、桥面上安装桁片,使以拱肋为主要承重构件的受力体系转变为双层桁架整体受力体系。为评估该方法的加固效果,以某50 m上承式拱桥为研究对象,运用有限元手段对比分析加固前后的力学性能。为进一步验证新加固改造法对提高原结构力学性能的有效性,完成10 m试验桥的荷载试验并对比分析结果。两种结果均表明:新型加固改造方法可以大幅提高桥梁承载力与刚度。对实桥进行有限元分析时,加固改造后拱脚和跨中最大压应力分别减小2.9、2.3 MPa,主梁最大上、下挠分别减小35.08%、27.42%;对试验桥进行静载加载时,加固改造后拱肋上缘与下缘最大应力分别减小82.68%、78.14%,拱肋最大上、下挠值分别减小97.47%、90.30%。故该加固改造方法积极有效,可尽早应用于工程实际。Due to the low design load level,inadequate maintenance and maintenance,and many years of operation,the mechanical properties of the early deck arch bridge can not satisfy the modern traffic requirements.To solve this problem,a new method of bridge reinforcement and reconstruction is proposed in this paper.By adding V-bars between arch ribs and main girder and installing trusses on the bridge deck,the traditional stress system with arch rib as the main load-bearing component is transformed into the overall stress system with double-layer truss.In order to evaluate the reinforcement effect of this method,the finite element analysis method was used to contrast and analyze the mechanical performances of a 50 m deck arch bridge before and after reinforcement.In order to further verify the effectiveness of the new reinforcement method in improving the mechanical properties of the original structure,the load test of 10 m test bridge was complete to analyze structure mechanical performances.The results indicate that the new reinforcement method can greatly improve the bearing capacity and stiffness of bridges.In the finite element analysis of the real bridge,the maximum compressive stresses at the arch foot and mid-span are reduced by 2.9 MPa and 2.3 MPa respectively,and the maximum up and down deflections of the main beam are reduced by 35.08% and 27.42% respectively.When the test bridge is loaded under static load,the maximum stresses at the upper and lower edges of the arch rib are reduced by 82.68% and 78.14% respectively,and the maximum up and down deflections of arch rib are reduced by 97.47% and 90.30% respectively.Therefore,this method is active and effective and should be applied to engineering practice as soon as possible.

关 键 词：桥梁工程 加固改造 桥梁结构体系 荷载试验 有限元 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]