Safety Analysis Of Bridge Driving In Side Wind Environment

Whether it is cross-sea bridge,cross-river bridge or urban overpass bridge,there is a certain clearance.That is to say,the bridge is always a certain distance from the ground,which leads to the significant difference between the wind environment on the bridge and the wind environment on the ground,especially,the incoming wind speed must be higher than the ground wind speed in the same position,which has a certain impact on the driving safety.In the process of driving vehicles in the process of bridge,side slip and roll accidents occur from time to time.Therefore,it is of certain application value to study the safety of bridge formation in strong wind environment.In this paper,taking Xiamen Haicang Bridge as the engineering background,the safety of several typical vehicles on the bridge and the factors affecting the safety are studied by means of numerical calculation method,wind tunnel test and theoretical analysis method.Considering the influence of various factors on bridge wind environment and vehicle aerodynamics,the specific research methods and safety evaluation methods are put forward.The 1:36 scale modeling and grid division of the bridge body are carried out by using ICEM CFD software.The pneumatic parameters of the bridge and the vehicle are calculated by means of two-dimensional and three-dimensional plane alternation research,and the characteristics of the flow field around the vehicle are analyzed under different working conditions.The wind tunnel test is used to formulate the wind tunnel test.The bridge with the same scale ratio as numerical simulation,according to the traffic flow statistics,customizes the representative car,off-road vehicle and freight car three kinds of models,independently designs a set of six-component force balance fixing device which can flexibly change the lane position,in order to get closer to the real driving environment,set the change of lane position,set up the attached components of railing wind barrier,the distribution of random vehicles and the comparison of different wind attack angles.The six-component force of three typical car bodies is collected respectively.In addition,this paper analyzes the test data by using the program compiled by ourselves,obtains the pneumatic parameters of the vehicle under each working condition,draws the relevant pneumatic parameter curves by using the drawing software,deduces the formula of the side slip and roll according to the characteristics of the force analysis of the vehicle,and calculates the critical wind 'speed under the two dangerous conditions of the side slip and roll of the vehicle according to the real climatic conditions of the position of the bridge.It provides valuable reference information for bridge driving safety under the action of strong wind.