双链式悬索桥的结构参数研究

发布时间：2018-01-30 20:30

本文关键词： 双链式悬索桥结构参数分析静力特性动力特性　出处：《兰州交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：由于双链式悬索桥在动力性能方面优于单链式悬索桥，结合双链式悬索桥的发展与建造明显滞后于单链式，本文有针对性的研究了双链式悬索桥结构参数对其静力特性和动力特性方面的影响。本文结合关头坝双链式悬索桥工程实例，利用有限元分析软件Midas/Civil建造了该工程实例的模型。通过调整各个参数，得到每个参数控制下该桥的静力和动力特性的数据。归纳及分析数据，得出以下结论。静力特性方面：（1）从主塔内力影响的角度出发，塔梁一般支撑的连接方式是最有利的一种连接方式；（2）双链式悬索桥在塔梁固结的情况下，其加劲梁跨中挠度值最小；（3）索塔固结的情况下，塔底产生的弯矩比索塔滑移的情况下产生的弯矩大的多；（4）增大悬索桥跨度比可以有效的减小缆索边跨应力，同时合理的增大跨度比，可以降低锚固端支座反力；（5）增大双链式悬索桥的矢跨比，能够明显的降低桥塔的内力，减小缆索应力，改善桥塔受力，但其竖向的整体刚度越小，加劲梁的跨中挠度值将增加。动力特性方面：（1）随着矢跨比的依次减小，双链式悬索桥的横弯、竖弯以及扭转的自振频率都会增加，一旦超过某一矢跨比值，其上升速度将减小；（2）在保持其他参数不变的情况下，依次修改双链式悬索桥的塔梁约束可以发现，，不同的约束方式对其自振频率有很大的影响，一般塔梁约束的自由度多少与其刚度和频率的增长成反比；（3）在不同的索塔约束方式条件下，保持其他参数不变，双链式悬索桥的自振频率基本没有变化；（4）跨度比对双链式悬索桥的自振频率基本无影响，对其刚度的变化也无影响；（5）随着加劲梁的纵梁的竖向刚度的增大，双链式悬索桥的竖弯、横弯及扭转自振频率会显著的增大。结合研究分析，可见实际工程中所采用塔梁约束形式，索塔约束形式和矢跨比都是比较合理的。
[Abstract]:Because the double chain suspension bridge is superior to the single chain suspension bridge in dynamic performance, the development and construction of the double chain suspension bridge lag behind the single chain suspension bridge obviously. In this paper, the influence of structural parameters on static and dynamic characteristics of double chain suspension bridge is studied. In this paper, the model of the double chain suspension bridge of critical dam is built by using the finite element analysis software Midas/Civil, and the parameters are adjusted. The static and dynamic characteristics of the bridge under the control of each parameter are obtained, the data are summarized and analyzed, and the following conclusions are obtained. From the point of view of the influence of the internal force on the main tower, the connection mode of the general support of the tower and beam is the most favorable connection mode. 2) under the condition of tower beam consolidation, the deflection of the stiffened beam in the middle span of the double chain suspension bridge is the smallest; 3) in the case of cable tower consolidation, the bending moment produced by the bottom of the tower is much larger than that by the sliding cable tower. (4) increasing the span ratio of suspension bridge can effectively reduce the span stress of cable side and reasonably increase the span ratio, which can reduce the reaction force of anchor end support; 5) increasing the rise-span ratio of the double-chain suspension bridge can obviously reduce the internal force of the bridge tower, reduce the cable stress and improve the stress of the bridge tower, but the smaller the overall vertical stiffness, the higher the mid-span deflection of the stiffened beam. In the aspect of dynamic characteristics: 1) with the decrease of rise-span ratio, the natural frequencies of transverse bending, vertical bending and torsion of double-chain suspension bridge will increase, and the rising speed will decrease when the ratio exceeds a certain rise-span ratio. 2) under the condition of keeping other parameters unchanged, it can be found that different constraint modes have great influence on the natural vibration frequency of double-chain suspension bridge by modifying the tower and beam constraints in turn. The degree of freedom of a general tower beam is inversely proportional to the increase of its stiffness and frequency. (3) the natural vibration frequency of the double-chain suspension bridge is basically unchanged under the conditions of different cable tower constraints and other parameters remain unchanged; (4) the ratio of span to span has no effect on the natural vibration frequency of the double-chain suspension bridge, nor does it affect the change of the stiffness of the bridge. 5) with the increase of vertical stiffness of stiffened beam, the natural frequencies of vertical bending, transverse bending and torsional vibration of double chain suspension bridge will increase significantly. According to the research and analysis, it can be seen that the tower beam constraint form, the cable tower constraint form and the rise-span ratio are reasonable in practical engineering.
【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.25

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