Study On Parameter Characteristics Of Wind-rain Induced Stay-Cable Vibration On Dongting Lake Bridge

Cable of cable-stayed bridge has many advantages,such as large flexibility, light weight, small damp and low natural frequency. It can easily be excited by wind, combination of wind and rain, traffic loads and so on, which leads to produce various kinds of violent vibration. Among these the wind-rain induced vibration is more harmful than others. Wind-rain induced vibration presents great complexity, which formation mechanism has a jillion problems are pressing for solution. So in resent decades, research on the wind-rain induced vibration has become one of the focus issues.To investigate the parameter characteristics of wind-rain induced stay-cable vibration, this thesis is on the basis of the data collection from the field experimental tests of wind-rain induced stay-cable vibration on Dongting Lake Bridge in Hunan province; and through statistically processing of valid data, get some meaningful results of the mechanism of wind-rain induced stay-cable vibration. The following is the main content of this paper.(1) A review of the achievement of the research works on these problems was made to summarize some common forms of wind induced stay-cable vibration and introduce the problems and dangers of wind-rain induced stay-cable vibration.(2) A test of wind-rain induced stay-cable vibration on Dongting Lake Bridge is Introducd. Data preprocessing were made to get the measured time histories of parameters in wind-rain induced stay-cable vibration.(3) A quantitative analysis were made on the relationship between wind speed, wind declination, rainfall and cable vibration, as well as response characteristics of these parameters.(4) To investigate the average net aerodynamic negative damping ratio with different time intervals, some distribution histograms of average net negative damping ratio were made by researching mode displacement components amplitudes with mode decomposition.(5) The three dimensional joint no exceeding probability and three dimensional joint exceeding probability were made by the joint distribution of wind-rain induced stay-cable vibration on Dongting Lake Bridge. This joint distribution was constructed by Copula theory.