Research For Surface Wind Pressure Distribution Of The Steel Box Girder Under Simultaneous Actions Of Wind And Rain

With the increasing span of the bridge,the combined effects of wind and rain have become factors in the construction of super typhoons hit the region span bridges can not be ignored.Large-span bridge structure is in the wind and rain combined effects of environment,bridge structural analysis and design theory rely on conventional single consideration wind farm environment and the establishment of a bridge structure response analysis and design,has been unable to meet the actual project needs,the reason is that the rain Field and the combined effects of the presence of wind and rain.Based on this,this paper relies on "twelfth-five" major scientific and technological projects of department of transportation,the topic name is wind rain effects monitoring and simulation research of the large bridges of the coupling observation of wind and rain and extraction technology research.Pilot group install wind pressure measurement system on Xia Zhang Bridge and extract air wind pressure?wind parameters data and rain data by bridge health monitoring system.Meanwhile,this paper analyze these data and research the law of the wind pressure of the steel box girder under simultaneous actions of wind and rain.Its main research contents are as follows:First,this paper carries on numerical simulation analysis bases on CFD method,and gained the CFD simulation of wind pressure diagram.Compared results of numerical simulation and results of testing.These showed the measured pressure steel box girder used in the outer surface of the pressure measurement system have certain reliabilitySecond,the typhoon "Lotus" and "Soudelor" wind characteristic draw the linear relationship between gust factor and turbulence intensity,and the linear relationship between turbulence intensity and the gust factor.This shows that the turbulence intensity factor and gust wind speed decreases features.Third,rainfall distribution through the analysis of typhoon "Lotus" and "Soudelor" during the storm and correlation analysis found that during the two typhoons were no large rainfall,and the rainfall and the average wind speed is not much correlation.Fourth,within 9m/s~ 16m/s,there is general pressure value in case of rain overall pressure ratio of no value in case of rain phase ratio,respectively,increases of 30%~42%.Fifth,with or without rain,wind angle of attack affects both nearby,web and pressure values of the windward side of the beam bottom nozzle,pressure values without rain wind conditions change the angle of attack compared to the case and there is rain more significant.