紊流风场中桥梁气动导数的识别  

Identification of Flutter Derivatives of Bridges in Turbulent Wind

作　　者：顾明[1] 张若雪[1] 项海帆[1] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《同济大学学报（自然科学版）》2000年第2期134-137,共4页Journal of Tongji University:Natural Science

基　　金：国家自然科学基金重大资助项目! ( 598954 10 ) ;国家杰出青年科学基金资助项目

摘　　要：基于作者提出的识别桥梁断面气动导数的新方法———总体最小二乘时域法 ,初步研究了紊流风场中气动导数的识别 .总体最小二乘时域法试验装置简单 ,克服了改进的Ibrahim时域法人为选择时延参数的不足 ,具有很高的精度和收敛性 .由平板理论解和江阴长江公路大桥的全桥气动弹性模型实验结果证实了该方法的正确性 .在模拟的紊流风场中 ,应用这一方法对平板和江阴长江大桥的节段模型进行了试验 ,识别了其气动导数 .试验结果初步表明 ,对具有良好流线型的桥梁断面 。A preliminary study on identification of flutter derivatives in turbulent wind using the new system identification technique——the global least-square method developed by the authors is presented in this paper. The method which only requires simple facilities can overcome the shortcomings of the MITD method proposed by Sarkar, et al, and has been verified by the theoretical solution of a thin plate and the results of the aeroelastic full model of the Jiangyin Bridge over the Yangtze River in smooth wind. A thin plate and the sectional model of the Jiangyin Bridge were tested in turbulent wind in a wind tunnel to extract their flutter derivatives. The results indicate that the effects of turbulence on flutter derivatives of those bridges with more streamlined deck cross section may be neglected.

关 键 词：大跨桥梁 紊流风场 气动导数 识别 总体最小二乘时域法 桥梁断面 风振机理 颤振 抖振 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]