摘要下承式钢管混凝土系杆拱桥中，吊杆与拱肋、系梁与拱肋、吊杆与系梁的连接节点是 整个结构的关键部位，并且各部分连接形式和受力都很复杂，分析和研究 节点 的受力性能及其影响因素，对提高桥梁的整体性能具有重要意义，并可以为同类桥梁的结构设计提供依据。本文采用数值分析方法，首先建立全桥空间有限元模型，进 行静 力计算分析；根据 受力分析结果，选取拱脚处、吊杆与系梁和横梁连接 节点 处、吊杆和拱肋连 接节点处作为细部分析 的对 象，根据节点细部模型截取原则 ， 确定了细部 模型中各个构件的 截取尺寸；分析并确定了细 部模型所要施加的边 界条件；据 此建 立了节点 细部有限元计算分析模型，进 行相 关 节点的 受力计算和分析。分析结果表明： 拱脚 节点 存在应力集 中现象 ，位置在系梁与横梁连接处以及拱肋与系梁的连接处，最大应力值为 220Mpa ，接近结构材料的屈服强 度345Mpa ，安全储备低。 针对此现象本文提出的设计修改意见是：将系梁腹板厚度由 14mm 改为 24mm ，系梁翼缘板厚度由 20mm 改为 30mm ，其他构件尺寸不变 ，修改后的模型各个构件计算应力值均比 未修改模型的应力 值小，且应力集中现象减弱 ， 最大应力值减小到 170Mpa ， 减小幅度为 23% 。 所选取的吊杆 、 系梁和横梁连接 节点 处，构件应力值分布均匀，变化幅度较小，最大等效应力不超 过76Mpa ， 位置在系梁与横梁上翼缘连接处 。 吊杆与拱肋连接处 ， 出现 应力集中现象，最大等效应力值为 96Mpa 。本文对下承式钢管混凝土系杆拱桥 节点 的受力研 究可为同类桥梁 的设计 提供参考，具有工程实用价值。61108
毕业论文关键词 钢管混凝土 下承式拱桥 节点 数值分析
Title A Single Span CFST Tied Arch Bridgenode force performance analysisAbstract Abstract Abstract AbstractUnder CFST Tied Arch Bridge, the tie bar and the rib, tie beam and rib,the tie bar and tie beam connection node is a key component of the wholestructure, and each part of the connection form force performance are verycomplicated, analysis and research the mechanical properties of the nodeand its influencing factors, to improve the overall performance of thebridge is important, and can provide similar bridges provide the basis forthe structural design.N umerical analysis method was used i n this paper, first create d full-bridgespace finite element model for the static calculation and analysis; By thestress analysis results, select de the foot arch, c onnected node of tiebar , tie beams and beams, connected node of tie bar and rib as the objectto detailed analyze . A ccording to the interception principles of thedetailed model to determine the interception size of each component in thelocal model; analyzed and identified boundary conditions of the local modelto be applied; which established finite element analysis local model ofthe node for force calculation and analysis.The analysis results showed that: the arch node exist de stressconcentration, the location at the junction s of tie beam connect ed withthe beam and arch connect ed with tie beam , the maximum stress was 220Mpa,close to the yield strength 345Mpa of the material, safety reserve was low.P roposed modifications opinion f or this phenomenon was : t hicken the tiebeam ’ s web thickness from 14mm to 24mm, t hicken the tie beam ’ s flange plate thickness from 20mm to 30mm, u nchanged the other component ’ s size ,calculated stress values of each component in the modified model is small erthan stress values in the unmodified model, and reduced stressconcentration, the maximum stress was reduced to 170Mpa, the reduc edamplitude is 23%. Stress of the selected connected nodes of tie bar, tiebeams and beams, distributed uniform, s maller change d, the maximumequivalent stress did not exceed 76Mpa, which occurred in the junction ofthe tie beam ’ s flange and the beam ’ s flange.The joints of the tie bar andthe rib occur ed stress concentration, the maximum stress wa s 96Mpa .This paper r esearch ed the force of the node in Under CFST arch bridge , whichcan provide reference for the design of similar bridges, and also haspractical value. 某单跨下承式钢管混凝土系杆拱桥节点的受力性能分析研究:http://www.751com.cn/gongcheng/lunwen_66716.html