大跨度步行桥人行激励的TMD水平向减振

2016-01-12袁正国

森林工程 2015年2期

大跨度步行桥人行激励的TMD水平向减振

袁正国

(中铁二十三局集团有限公司，成都 610072)

摘要：大跨度步行桥在人行激励下的水平振动将引起行人不适和结构损坏，为了对大跨度步行桥人行激励水平振动进行减震控制，以某大跨度景观步行桥为例研究了人行激励的特征和步行桥的振动特性，以人行桥舒适度为目标进行了TMD控制设计，通过数值分析进行了减振控制研究。研究结果表明，TMD质量比取1%~3%时有明显的减震效果，且TMD质量块越大，控制效果越好；TMD水平减振对大跨度步行桥人行激励引起的水平振动减震效果明显，位移和加速度控制效果分别达到21.3%和20.2%；MTMD的控制效果要比单个TMD的控制效果要好，但当数目超过5个时，随着TMD的个数增多，控制效果增加的并不明显。

关键词：步行桥；人行激励；水平振动；TMD；振动控制

中图分类号：S 791；U 442

文献标识码：A

文章编号：1001-005X(2015)02-0154-05

Abstract：The horizontal vibration of long-span footbridge by human-induced loads will cause pedestrians discomfort and damage of the structure.In order to control the long-span footbridge’s horizontal vibration，the author studied the characteristics of the human-induced loads and vibration characteristics with an example of a long-span footbridge，and conducted the TMD control design aiming at the comfort and research damping control by numerical analysis.The results showed that the vibration control effect was significant when TMD mass ratio ranged between 1% and 3%，and the larger the TMD mass，the better the control.The effect of TMD horizontal vibration was obvious，and the control effect of displacement was 21.3% and the control effect of acceleration was 20.2%.The effect of MTMD control was better than TMD，but when the number of TMD was more than 5，the control effect was not significantly increased with the increase of TMD.

Keywords：footbridge；human-induced loads；horizontal vibration；TMD；vibration control

收稿日期：2014-10-11

基金项目：河北省自然科学基金项目(E2013203183)

作者简介：第一袁正国，博士，副教授、高级工程师。研究方向：结构抗震、土木工程施工与管理。E-mail：250439351@qq.com

TMD Horizontal Vibration Control of Large-spanFootbridge under Human-induced Loads

Yuan Zhengguo

(China Railway 23th Construction Bureau.Co，Ltd.，Chengdu 610072)