苏通大桥实测强风湍流积分尺度的对比研究

Comparable study on turbulence integral scale of measured strong wind on Sutong Bridge

湍流积分尺度是体现风特性的重要指标之一,而现场实测是获得工程结构准确可靠的风特性的唯一有效手段。本文利用苏通大桥结构健康监测系统(SHMS)采集的风特性数据库,选取该桥址区2008年夏季的"凤凰"、"海鸥"台风及冬季北风为样本进行强风特性分析。其中采用4种常用计算方法重点研究了桥址区强风的积分尺度,并对比了不同方法的计算结果以验证其可靠性。最后分析了湍流积分尺度随高度和平均风速等的变化规律。结果表明:湍流积分尺度与风速之间无确定关系,塔顶湍流积分尺度较跨中大。分析结果充实了苏通大桥风特性数据库,可为湍流积分尺度的分析计算提供参考,并为苏通大桥的强风环境和抗风评估提供了实测依据。

Turbulence integral scale is one of the important parameters to reflect wind characteristics.Field measurement is the only efficient way to get the accurate and reliable wind characteristics for engineer-ing structures.The wind data recorded by structural health monitoring system（SHMS） of Sutong Bridge is used in the paper.The typhoons including Fung-wong,Kalmaegi in summer and the Northern Wind in winter of 2008are taken as the examples to analyze the turbulence characteristics of the strong wind records.The turbulence integral scale of the recorded wind data is investigated with four common methods,and the analysis results using different methods are compared to validate the reliability of the calculation.The relationships between the turbulence integral scale and the height as well as the mean wind speed are analyzed.Results show that there is no clear relationship between the turbulence integral scale and wind speed,and the turbulence integral scale at the top of the tower is larger than that at the mid-span.Results can enlarge the wind database of the Sutong Bridge,provide reference for analysis of the turbulence integral scale,and establish the measurement basis for the strong wind environment and wind resistance evaluation of the Sutong Bridge.