下承式连续梁拱组合体系钢桥的力学特性研究

发布时间：2018-01-18 11:28

本文关键词：下承式连续梁拱组合体系钢桥的力学特性研究　出处：《东南大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来,随着钢材产量的迅速增长,越来越多的钢结构桥梁出现在我国桥梁工程建设中。下承式梁拱组合体系钢桥兼具钢桥与连续梁拱组合体系桥的优点,在保持受力合理的同时降低了建筑高度,建造速度快且造型美观,工程应用前景广阔。本文结合江苏省宜兴市梅林大桥工程,从梁拱协作机理、结构参数分析、钢箱梁剪力滞效应以及结构极限承载力等四个方面,对下承式连续梁拱组合体系钢桥的力学特性进行了研究。(1)利用结构力学方法,推导出此类桥拱肋荷载分担比的计算公式,分析了结构总体布置参数对其影响,发现下承式连续梁拱组合体系桥的主跨拱肋荷载分担比例受边跨主梁影响较小,中跨主梁和吊杆刚度对拱肋受力影响较大；(2)建立杆系单元模型,分析了梁拱刚度比、拱肋倾角及横撑布置形式对结构振动频率与振型的影响；(3)建立ABAQUS全桥板壳单元模型,对钢箱梁的剪力滞效应进行了分析。比较了车辆荷载与车道荷载的剪力滞效应,发现车道荷载在主跨产生的剪力滞系数小于车辆荷载,而二者在边跨产生的剪力滞系数接近。由车辆荷载产生的剪力滞系数在偏载工况下略大于正载工况；(4)建立ABAQUS显式动力分析模型,对背景工程桥梁的极限承载力进行了分析、研究。得到了各工况下结构控制截面的极限内力值,并计算出结构活载安全系数的最小值为8.6倍设计车道荷载及人群荷载,表明结构运营安全储备充足；(5)通过背景工程桥梁成桥荷载试验相关数据,分析了成桥状态下的静力与动力特性,对比了现场实测值与有限元模型计算值,验证了本文建立的杆系与板壳有限元模型的正确性。
[Abstract]:In recent years, with the rapid growth of steel output, more and more steel bridges appear in the construction of bridge engineering in China. The through beam and arch composite system steel bridge has the advantages of steel bridge and continuous beam arch composite system bridge. In keeping with reasonable force at the same time reducing the height of the building, fast construction speed and beautiful shape, the application of the project is broad. Combined with the Meilin Bridge Project in Yixing City, Jiangsu Province, from the beam and arch cooperation mechanism, structural parameters analysis. Based on the shear lag effect of steel box girder and the ultimate bearing capacity of the structure, the mechanical properties of steel bridge with through continuous beam and arch composite system are studied. 1) the structural mechanics method is used. The calculation formula of load sharing ratio of arch rib of this kind of bridge is deduced, and the influence of overall structure layout parameters on it is analyzed. It is found that the ratio of load sharing of main span arch rib of through continuous beam and arch composite system bridge is less affected by side span main beam. The stiffness of mid-span girder and suspender has a great influence on the arch rib. (2) the element model of bar system is established, and the influence of stiffness ratio of beam and arch, inclination angle of arch rib and arrangement of transverse braces on the vibration frequency and vibration mode of the structure are analyzed. The shear lag effect of steel box girder is analyzed, and the shear lag effect of vehicle load and driveway load is compared. It is found that the shear lag coefficient of lane load in the main span is smaller than that of the vehicle load, while the shear lag coefficient generated by both of them in the side span is close. The shear lag coefficient caused by the vehicle load is slightly larger than that under the positive load condition. (4) the ABAQUS explicit dynamic analysis model is established, the ultimate bearing capacity of the bridge in background engineering is analyzed and studied, and the limit internal force of the structure control section is obtained under various working conditions. The minimum value of live load safety factor is 8.6 times design lane load and crowd load, which indicates that the structure operation safety reserve is sufficient. 5) the static and dynamic characteristics of the bridge under the condition of the bridge are analyzed through the relevant data of the bridge load test in the background engineering, and the field measured values are compared with the calculated values of the finite element model. The correctness of the finite element model of bar system and shell is verified.
【学位授予单位】：东南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U441;U448.36

【参考文献】