Research On The Reliability Of Wind Barrier On Railway Bridge

Train overturning accidents induced by strong winds still occur now and then,and wind barriers can reduce these accidents efficiently.Scholars in domestic and foreign have been working on the wind barrier to the structure design on basis of deterministic method and aerodynamic characteristics,such as height,the distance between track,porosity rate,etc.The research on the performance of wind barrier is less according to the reliability theory,but the main load on the wind barrier is natural wind load and train-induced pulsating wind load,which are random,so the research on wind barrier reliability is essential.In this paper,the static and dynamic reliability of the member and the structural system of wind barrier on railway bridge under the natural wind load and train-induced pulsating wind load is calculated,and the reliability is evaluated to ensure the safety of wind barrier and to prevent wind barrier from overturning under the strong wind load which will seriously threaten the safety operation of the train.At the same time,the parameter sensitivity of the static and dynamic reliability of the structural system of wind barrier is also analyzed to find out the important influencing factor.The wind barrier with certain porosity has various forms and low cost.Therefore,the wind barrier with certain porosity for the windproof plate is considered as example to research the reliability of wind barrier on the railway bridge in this paper.The reliability calculation of wind barrier mainly considers horizontal natural wind load and train-induced pulsating wind load.The research is mainly divided into two parts,that is,the static reliability and dynamic reliability of wind barriers:1)The static reliability is analyzed considering the peak value of both natural wind load and train-induced pulsating wind load.Theoretical calculation and numerical simulation method are adopted respectively.2)The dynamic reliability is analyzed considering the average wind load,pulsating load of natural wind and train-induced pulsating wind load,then the response surface function of the member and structural system of wind barrier is simulated by the quadratic response surface method,and their reliability index and failure probability are calculated,and their time-dependent reliability index and time-dependent failure probability are also calculated.Finally,the parameter sensitivity of the static and dynamic reliability index of the structural system of wind barrier is also studied.