高速列车经过时跨线天桥表面风压小波分析

摘要

列车风荷载是临近高速铁路建筑物设计和确定相关建筑限界必须考虑的重要问题。跨线天桥是典型高速铁路临近建筑物，列车经过时作用在跨线天桥表面上的气动力不可忽视。基于跨线天桥表面风压实测试验，对实测风压进行小波变换，分析天桥表面风压的脉动特性和风压脉冲影响，识别风压在不同频段的分布情况。分析表明，天桥表面压力分量在低频段比较大，在高频段比较小；风压能量在低频段比较大，在高频段比较小；列车风压的低频部分起控制作用，高频部分影响比较小。小波分析对研究跨线结构表面列车风压有很大作用，其分析方法和工程应用方法值得进一步研究。%It is necessary to predict aerodynamic loads on buildings near tracks during high-speed train passage in order to design these buildings and determine their limits.An over-line bridge is a typical building near tracks,the train-induced flow and its aerodynamic effects on the bridge surface can not be ignored.Based on the wind pressure measurement test data of an over -line bridge,the measured wind pressure was transformed with wavelet transformation.The surface wind pressure fluctuation characteristics were analyzed and the wind pressure distribution in different frequency bands was identified.Analysis showed that the surface wind pressure components in lower frequency bands are larger,while those in higher frequency bands are smaller;the wind pressure energy in lower frequency bands is larger and that in higher frequency bands is smaller;the lower frequency part of the wind pressure has a larger impact on the bridge,while the higher frequency part has a smaller impact.Wavelet analysis was helpful to the study on surface wind pressure of the over-line bridge,its analysis and application techniques were worth further investigating.