路面不平顺激励作用下悬浮隧道锚索的动力响应  

Dynamic Response of the Tethers of a Submerged Floating Tunnel Caused by Road Undulation Excitation

作　　者：刘斌[1] 刘祚秋[1] 巫志文[1] 

机构地区：[1]中山大学工学院应用力学与工程系,广州510006

出　　处：《现代隧道技术》2017年第5期115-121,共7页Modern Tunnelling Technology

基　　金：国家自然科学基金资助项目(10672194;11172334)

摘　　要：为了研究悬浮隧道锚索在路面不平顺激励作用下的动力特性,文章在锚索振动方程中考虑了锚索的垂度效应,建立了锚索在路面不平顺激励作用下的非线性振动方程,分别运用虚拟激励法和龙格-库塔积分法对悬浮隧道锚索的振动响应进行了频域分析和时程分析,并讨论了锚索阻尼比、初张力、轨道功率谱和车速对其振动响应的影响。研究结果表明:锚索振动系统的初张力、阻尼比越大,锚索的位移功率谱密度就越小;随着车速的增加,锚索跨中位移逐渐变大;由于等效线性化的影响,频域分析得到的位移均方根比时域分析得到的位移均方根要偏小一些。In order to analyze the dynamic characteristics of the tethers of a submerged floating tunnel subjected to road undulation excitation, a non-linear vibration equation of tethers was set up by taking the sag of the tether into account. The vibration response of the frequency-domain and time-history analysis of the tethers was obtained by applying the pseudo-excitation method and the Runge-Kutta method. Effects of the damping ratio and the initial tension of the tethers, track power spectrum and vehicle speed on the vibration response of the tethers were ana- lyzed. It may be concluded that the larger the damping ratio and initial tension of the tethers the smaller the dis- placement power spectrum density of the tethers; the displacement at the middle position of the tethers increases gradually as the vehicle speed increases; and due to the influence of the equivalent linearization, the displacement root mean square obtained by the frequency-domain analysis is smaller than that of the time-domain analysis.

关 键 词：悬浮隧道 锚索 路面不平顺 虚拟激励法 

分 类 号：U459.5[建筑科学—桥梁与隧道工程]