梁式桥地震碰撞响应与防落梁措施研究

发布时间：2018-03-04 04:39

本文选题：梁式桥　切入点：碰撞　出处：《重庆交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：众所周知，桥梁是公路交通网络中一个关键节点，其抗震防灾功能越来越受到人们的关注，在强烈地震作用下，梁式桥由于相邻桥跨之间存在动力特性的差异，或者受到非一致性地震动作用的影响，上部结构在顺桥向容易发生较大的位移，引起梁体间碰撞或者落梁，导致整个交通网络瘫痪。本课题结合“云南省交通运输厅的山区高低墩抗震特性及减隔振措施研究”项目，研究一种有效防止梁体间的碰撞和防落梁装置，本文主要开展的研究工作如下： ①查阅大量有关桥梁结构在地震作用下发生碰撞或落梁的灾害实例，，总结了桥梁碰撞和落梁问题的研究现状和方法，回顾了美国、日本和中国防落梁系统规范，并探讨了各种防落梁装置的优缺点。 ②运用MIDAS CIVIL2013建立40米多跨连续梁式桥的基本动力模型，在此基础上分析了40米梁式桥的地震响应特性。 ③通过分析发现梁式桥在地震作用下，桥台伸缩缝处梁体间比中间伸缩缝处梁体间更容易发生碰撞或落梁；变高墩比等高墩伸缩缝处梁体更容易发生碰撞；高墩比低墩容易发生碰撞或落梁，且伸缩缝处梁体间的碰撞力都非常大，不可忽视，急需解决梁体间的碰撞或落梁。 ④通过试算，研发了一种带阻尼器的防落梁装置（目前处于试验阶段），这种防落梁装置利用阻尼器在地震中耗能来阻止或减轻梁体间的碰撞同时起到防落梁的作用，即使防落梁装置中的阻尼器在强烈地震作用下损坏，防落梁装置依靠自身强度也可以起到防落梁的目的。 ⑤探讨设置防落梁装置后的应用效果：防落梁装置设置后除了减少梁体间相对位移起到防碰撞和防落梁的目的外，还可以减轻铅芯橡胶支座顺桥向的相对位移，使铅芯橡胶支座在每个桥墩上分摊的剪力更小更均匀，有效保护了铅芯支座使用功能。 ⑥防落梁装置设置在梁与墩之间比设置在梁与梁之间有效；变高墩须设置防落梁装置；防落梁装置设在高墩上比设置在低墩上应用效果要好；板式橡胶支座比铅芯橡胶支座更需要设置防落梁装置。
[Abstract]:As we all know, bridge is a key node in highway traffic network, and its anti-seismic and disaster prevention function has been paid more and more attention. Under the strong earthquake, the dynamic characteristics of beam bridge are different because of the adjacent bridge span. Or under the influence of inconsistent ground motion, the superstructure is prone to displace in the direction of the bridge, causing the beam to collide or fall to the beam. The whole traffic network is paralyzed. In this paper, combining with the project of "study on Seismic characteristics and Vibration isolation measures of High and low Pier in mountainous area of Yunnan Provincial Traffic and Transportation Department", an effective device for preventing collision and falling beam between beams is studied. The main research work of this paper is as follows:. The main contents are as follows: 1. Referring to a large number of disaster examples of bridge structures colliding or falling beams under earthquake, this paper summarizes the research status and methods of bridge collision and beam fall, and reviews the specifications of anti-falling beam systems in the United States, Japan and China. The advantages and disadvantages of various anti-falling beam devices are also discussed. (2) the basic dynamic model of 40m multi-span continuous beam bridge is established by using MIDAS CIVIL2013, and the seismic response characteristics of 40m beam bridge are analyzed. (3) through the analysis, it is found that the beam body at the abutment expansion joint is more likely to collide or fall under the earthquake than the beam body at the middle expansion joint, and that the beam body at the expansion joint of the same height pier is more likely to collide with the beam body when the pier is higher than the beam body at the same height pier. High piers are more likely to collide or fall beams than low piers, and the collision force between beams at the expansion joint is very large, which can not be ignored, so it is urgent to solve the collision or falling beam between beams. (4) through trial calculation, a kind of anti-falling beam device with dampers has been developed. (at present, the device is in the experimental stage. This device uses dampers to prevent or reduce the collision between beams during earthquakes, and it plays the role of preventing beams from falling off at the same time. Even if the dampers in the anti-falling beam device are damaged by strong earthquake, the anti-falling beam device can also play the purpose of preventing the falling beam by relying on its own strength. 5. The application effect of setting the anti-falling beam device is discussed. After the installation of the anti-falling beam device, besides reducing the relative displacement between the beams, it can also reduce the relative displacement of the lead-rubber bearing along the bridge, besides the purpose of preventing the collision and the anti-falling beam. The shear force of lead rubber bearing on each pier is smaller and more uniform, which effectively protects the function of lead bearing. (6) the anti-falling beam device is more effective between beam and pier than between beam and beam, and the anti-falling beam device must be set up on the variable height pier, and the anti-falling beam device is better than the application effect on the low pier. Plate rubber bearings need more anti-falling beam than lead rubber bearings.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U442.55;U441

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