大跨度异形钢箱梁人行桥的舒适性评价与振动控制
发布时间：2018-12-23 12:53
【摘要】：人行桥作为现代交通的重要通道,在城市交通以中发挥着重要的作用,它既为行人的出行提供了方便,同时又美化了城市环境。随着社会的发展,各类轻质、高强、高耐久的材料开始在人行桥的建设中得到广泛的应用,人行桥的结构形式也日渐复杂。由于大跨异形钢箱梁人行桥的结构轻巧、跨度较大,导致人行桥在行人的作用下易产生过度振动,引起行人的不适。目前国内规范对于人行桥舒适性评价以及振动控制尚未有充足的经验和完善的制度,本文以一座典型的大跨异形钢箱梁人行桥为例,对人行桥基于不同指标的舒适性评价及振动控制进行了系统的研究。(1)系统的分析了舒适性评价的方法及指标,总结了国内外规范对于舒适性评价的要求,包括频率标准以及响应标准。并分析了国内外规范对于行人荷载模式的要求,选定了用于动力响应计算的行人步行荷载模型,确定了四种经典行走步频下的单步落足曲线以及人群荷载的简化模型。(2)基于频率法对大跨异形钢箱梁人行桥进行舒适性评价。对本文所选景观人行桥中结构复杂的两联进行了动力特性的分析,确定桥梁的基频较低的振型。然后对实际桥梁进行现场模态测试,对桥梁基频的计算进行校核,并以各国规范为依据基于避开敏感频率法对桥梁的舒适性进行了初步评价,以确定是否需要进行桥梁在行人荷载下的动力响应计算。(3)基于响应法对大跨异形钢箱梁桥进行舒适性评价。根据行人在不同情况下行走的步频,基于强迫振动理论,拟定了不同行走频率及行人数量的步行工况,对大跨钢箱梁桥梁在各种工况下的动力响应进行了计算,并且按照理论计算工况对实际桥梁进行了现场步行荷载加载试验,得到了各工况下桥梁的振动响应,对计算结果进行验证。基于限制动力响应法,按照规范对桥梁在实际使用中的舒适性进行评价,得出桥梁在人群荷载作用下的振动响应并不能满足舒适性要求,需要对桥梁采取一定的措施进行振动控制。(4)在基于频率法和基于响应法对桥梁的舒适性评价的基础上,针对大跨钢箱梁桥在步行荷载作用下最易发生共振的振型,进行了调谐质量阻尼器(TMD)的设计,对大跨钢箱梁人行桥进行振动控制,对不同情况下TMD的控制效果进行了计算和评价,并对桥梁安装TMD后的实际减振效果进行了现场实测。在安装TMD进行振动控制之后,桥梁的舒适性问题得到很好的改善,达到正常使用对于人行桥舒适性的要求。
[Abstract]:Pedestrian bridge, as an important passage of modern traffic, plays an important role in urban traffic. It not only provides convenience for pedestrians, but also beautifies the urban environment. With the development of society, all kinds of lightweight, high-strength, high-durability materials have been widely used in the construction of pedestrian bridge, and the structure of pedestrian bridge is becoming more and more complex. Due to the light structure and large span of the large-span steel box girder footbridge, it is easy to produce excessive vibration under the action of pedestrians and cause discomfort for pedestrians. At present, the domestic code has not enough experience and perfect system for comfort evaluation and vibration control of footbridge. This paper takes a typical large-span steel box girder footbridge as an example. The comfort evaluation and vibration control of footbridge based on different indexes are systematically studied. (1) the methods and indexes of comfort evaluation are analyzed systematically, and the requirements for comfort evaluation in domestic and foreign codes are summarized. Including frequency standard and response standard. The requirements of pedestrian load modes in domestic and foreign codes are analyzed, and a pedestrian load model for dynamic response calculation is selected. The single step foot curve and the simplified model of crowd load under four kinds of classical walking frequency are determined. (2) based on the frequency method, the comfort of large-span special-shaped steel box girder footbridge is evaluated. In this paper, the dynamic characteristics of the complex structure of the bridge are analyzed, and the vibration modes of the bridge with low fundamental frequency are determined. Then the field modal test is carried out on the actual bridge, the calculation of the basic frequency of the bridge is checked, and the comfort of the bridge is preliminarily evaluated on the basis of avoiding the sensitive frequency method based on the national codes. In order to determine whether it is necessary to calculate the dynamic response of bridges under pedestrian loads. (3) based on the response method, the comfort of long-span special-shaped steel box girder bridges is evaluated. According to the walking frequency of pedestrians under different conditions and based on the theory of forced vibration, the walking conditions of different walking frequencies and the number of pedestrians are worked out, and the dynamic responses of long-span steel box girder bridges under various working conditions are calculated. According to the theoretical calculation condition, the actual bridge is subjected to the field loading test of walking load, and the vibration response of the bridge under various working conditions is obtained, and the calculated results are verified. Based on the limited dynamic response method, the comfort of the bridge in practical use is evaluated according to the code, and it is concluded that the vibration response of the bridge under the action of crowd load can not meet the requirements of comfort. Some measures should be taken to control the vibration of the bridge. (4) based on the evaluation of the comfort of the bridge based on the frequency method and the response method, the vibration mode of the long-span steel box girder bridge is most likely to occur under the action of walking load. The tuned mass damper (TMD) is designed to control the vibration of the long span steel box girder footbridge. The control effect of TMD is calculated and evaluated under different conditions. The actual vibration absorption effect of the bridge after the installation of TMD is measured on the spot. After the installation of TMD for vibration control, the comfort problem of the bridge has been improved very well, which can meet the requirements for the comfort of the footbridge in normal use.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U441;U448.11
本文编号：2390007
[Abstract]:Pedestrian bridge, as an important passage of modern traffic, plays an important role in urban traffic. It not only provides convenience for pedestrians, but also beautifies the urban environment. With the development of society, all kinds of lightweight, high-strength, high-durability materials have been widely used in the construction of pedestrian bridge, and the structure of pedestrian bridge is becoming more and more complex. Due to the light structure and large span of the large-span steel box girder footbridge, it is easy to produce excessive vibration under the action of pedestrians and cause discomfort for pedestrians. At present, the domestic code has not enough experience and perfect system for comfort evaluation and vibration control of footbridge. This paper takes a typical large-span steel box girder footbridge as an example. The comfort evaluation and vibration control of footbridge based on different indexes are systematically studied. (1) the methods and indexes of comfort evaluation are analyzed systematically, and the requirements for comfort evaluation in domestic and foreign codes are summarized. Including frequency standard and response standard. The requirements of pedestrian load modes in domestic and foreign codes are analyzed, and a pedestrian load model for dynamic response calculation is selected. The single step foot curve and the simplified model of crowd load under four kinds of classical walking frequency are determined. (2) based on the frequency method, the comfort of large-span special-shaped steel box girder footbridge is evaluated. In this paper, the dynamic characteristics of the complex structure of the bridge are analyzed, and the vibration modes of the bridge with low fundamental frequency are determined. Then the field modal test is carried out on the actual bridge, the calculation of the basic frequency of the bridge is checked, and the comfort of the bridge is preliminarily evaluated on the basis of avoiding the sensitive frequency method based on the national codes. In order to determine whether it is necessary to calculate the dynamic response of bridges under pedestrian loads. (3) based on the response method, the comfort of long-span special-shaped steel box girder bridges is evaluated. According to the walking frequency of pedestrians under different conditions and based on the theory of forced vibration, the walking conditions of different walking frequencies and the number of pedestrians are worked out, and the dynamic responses of long-span steel box girder bridges under various working conditions are calculated. According to the theoretical calculation condition, the actual bridge is subjected to the field loading test of walking load, and the vibration response of the bridge under various working conditions is obtained, and the calculated results are verified. Based on the limited dynamic response method, the comfort of the bridge in practical use is evaluated according to the code, and it is concluded that the vibration response of the bridge under the action of crowd load can not meet the requirements of comfort. Some measures should be taken to control the vibration of the bridge. (4) based on the evaluation of the comfort of the bridge based on the frequency method and the response method, the vibration mode of the long-span steel box girder bridge is most likely to occur under the action of walking load. The tuned mass damper (TMD) is designed to control the vibration of the long span steel box girder footbridge. The control effect of TMD is calculated and evaluated under different conditions. The actual vibration absorption effect of the bridge after the installation of TMD is measured on the spot. After the installation of TMD for vibration control, the comfort problem of the bridge has been improved very well, which can meet the requirements for the comfort of the footbridge in normal use.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U441;U448.11
【参考文献】
相关期刊论文 前7条
1 俞孔坚;曹扬;;江苏睢宁水袖桥[J];建筑学报;2011年04期
2 马汝建,赵东,王威强,蔡冬梅;ETMD系统在振动控制中的应用[J];济南大学学报(自然科学版);2005年01期
3 孙利民,闫兴非;人行桥人行激励振动及设计方法[J];同济大学学报(自然科学版);2004年08期
4 陆飞,程文椡,李爱群;南京电视塔风振主动控制的实施方案研究[J];东南大学学报(自然科学版);2002年05期
5 李春祥;地震作用下高层建筑TMD控制研究与设计[J];上海交通大学学报;1999年06期
6 李爱群，瞿伟廉，，程文 ;南京电视塔风振的混合振动控制研究[J];建筑结构学报;1996年03期
7 张敏政;工程抗震的新领域——结构振动控制[J];地震学报;1993年03期
相关博士学位论文 前1条
1 宋志刚;基于烦恼率模型的工程结构振动舒适度设计新理论[D];浙江大学;2003年
相关硕士学位论文 前3条
1 金志坚;人行桥人致振动分析[D];湖南大学;2010年
2 陈阶亮;行人激励下人行天桥的振动舒适性研究[D];浙江大学;2007年
3 伍定一;TMD对钢结构人行天桥的振动控制研究[D];长沙理工大学;2007年
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