摘要The combination of Rayleigh's energy method and Southwell's frequency composition method denoted the fundamental vibration frequencies of the freestanding pylon of suspension bridges as the composition of several subsystem frequencies. The subsystems consisted of deformation and inertia components. Thus, the algorithm for calculating the fundamental vibration frequency of the freestanding pylon of suspension bridges was derived through the rational selection of the deflection function. Take the middle steel pylon of Taizhou Bridge as a calculation example. The impact of top additional mass ratio, structure shear deformation, and vibration of the bearing platform on fundamental vibration frequency was analyzed. The numerical calculation and real bridge field vibration test show that (1) the fundamental vibration frequency of the pylon decreases as top additional mass ratio increases, and (2) the vibration of the bearing platform should not be ignored even if ignoring shear deformation only has a slight impact on the calculation results. The algorithm is not only suitable for pylons with a fixed base or additional mass at the top but also for other high buildings, chimneys, and structures with complicated sections.
Abstract：The combination of Rayleigh's energy method and Southwell's frequency composition method denoted the fundamental vibration frequencies of the freestanding pylon of suspension bridges as the composition of several subsystem frequencies. The subsystems consisted of deformation and inertia components. Thus, the algorithm for calculating the fundamental vibration frequency of the freestanding pylon of suspension bridges was derived through the rational selection of the deflection function. Take the middle steel pylon of Taizhou Bridge as a calculation example. The impact of top additional mass ratio, structure shear deformation, and vibration of the bearing platform on fundamental vibration frequency was analyzed. The numerical calculation and real bridge field vibration test show that (1) the fundamental vibration frequency of the pylon decreases as top additional mass ratio increases, and (2) the vibration of the bearing platform should not be ignored even if ignoring shear deformation only has a slight impact on the calculation results. The algorithm is not only suitable for pylons with a fixed base or additional mass at the top but also for other high buildings, chimneys, and structures with complicated sections.
基金资助:Supported by the National Natural Science Foundation of China(No.90815017);the Jiangsu Province Traffic Technology Project(No.08Y29);and the University Science Research Project of Jiangsu province of China (No.11KJB560002)
通讯作者:
WANG Jun, wangjun3312@njut.edu.cn
E-mail: wangjun3312@njut.edu.cn
引用本文:
王俊, 赵慧敏, 刘伟庆, 韩晓健, 张界杰. 悬索桥裸塔振动基频快速算法与试验研究[J]. Journal of Highway and Transportation Research and Development, 2013, 7(1): 28-33.
WANG Jun, ZHAO Hui-min, LIU Wei-qing, HAN Xiao-jian, ZHANG Jie-jie. A Rapid Algorithm of Fundamental Frequency for the Freestanding Pylon of Suspension Bridges. Journal of Highway and Transportation Research and Development, 2013, 7(1): 28-33.
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2013, Vol. 7 
