Study On The Mechanism And Prediction Of Snowdrift Hazard On Mountain Expressway

The 24 th winter Olympic Games will be jointly held by Beijing and zhangjiakou in 2022.In order to improve the transport capacity during the games and accelerate the realization of the beijing-tianjin-hebei coordinated development,a expressway directly connecting Beijing and zhangjiakou was built.The expressway passing through mountainous areas has a large average annual snowfall,which is very likely to cause road snowdrift hazard and hinder the normal operation of the expressway.This paper takes Yanchong Expressway as the background,the numerical simulation of snowdrift hazard on expressways in snowy mountainous areas is carried out,and the prediction models for snowdrift hazard on expressways in mountainous areas are obtained.Finally,the prediction models are applied to predict and analyze the snowdrift hazard of typical sections of Yanchong Expressway.First of all,the origins and influencing factors of snowdrift hazard on expressways in mountainous areas are studied and analyzed,and put forward the basic method of applying numerical simulation to study snowdrift hazard on expressways in mountainous areas.In order to obtain the maximum agreement between the model used in numerical simulation and the real road condition,the key parameters of the model were set and hypothesized before the typical sections are studied and analyzed by using the method of numerical simulation.Secondly,according to the different forms of roadbed adopted by expressway,five factors are considered:wind speed at 10 m above ground,relative elevation of mountain,horizontal distance between roadbed and mountain along expressway,height of embankment/cutting,slope of embankment/cutting slope.A large number of numerical simulation studies were designed and carried out on different types of typical roadbed section by using FLUENT software and orthogonal regression test theory,and the prediction models of snowdrift hazard of mountain expressway with different types of roadbed were obtained.Through the further analysis of the prediction model,the main factors affecting the snowdrift hazard of expressway with different types of roadbed are obtained,and the degree of the impact is also studied.Finally,on the basis of the prediction models obtained from the above numerical simulations,using the method of comparing the numerical simulation results with the predicted model results,the snowdrift hazards on typical sections of Yanchong Expressway are predicted and analyzed.At the same time,the reliability of the prediction models are verified again by the actual working conditions,which provides a reference for the further study of the snowdrift hazard prediction.