Research On Prevention Technology Of Snowdrift On Jing-Xin Expressway(G7) At The Northern Foot Of Tianshan Mountains In The East Of Xinjiang

The occurrence of wind and snow disaster will lead to a large amount of snow on the road to block traffic,reduce visibility and affect traffic safety,which restricts the function of highway transportation seriously and causes great economic losses.Barkol-Mori project of Jing-Xin Expressway(G7)is located at the northern foot of Tianshan Mountains in the east of Xinjiang.The route is prone to wind and snow disaster in winter.In this paper,the distribution characteristics of snowdrift on the expressway are investigated and analyzed and the vulnerable sections of wind and snow disaster are found out in order to ensure the safe operation of the line and reduce the impact of wind and snow disaster.The characteristics of wind field and snow cover of different subgrade sections are studied through the establishment of numerical analysis model.Furthermore,the effects of different design parameters of the snow board are compared,and suggestions on the height,porosity,setting position and length of the snow board are given.The main contents and achievements of this paper are as follows:(1)The terrain and climate conditions at the northern foot of Tianshan Mountain in the east of Xinjiang make the wind and snow disasters in Barkol-Mori section of Jing-Xin Expressway(G7)present uneven distribution in space and time.Some sections have disorderly wind phenomenon,which makes the highway project will be affected by natural wind and snow disaster.At the same time,because of the change of original microclimate and micro terrain conditions within the scope of the route,serious wind and snow disaster will appear in some sections.In order to fully understand the meteorological and snow distribution along the Barkol-Mori highway,this paper analyzes the monitoring data of Barkol and Mori County meteorological stations at both ends of the line.The characteristics of snowdrift along the highway are mastered through the investigation of snow conditions along the highway.The distribution rules of snow density,snow depth and wind velocity in the construction project area of Barkol-Mori highway are obtained.The characteristics and the occurrence mechanism of wind and snow disaster of subgrade with different cross-sections are presented.(2)According to the distribution of snowdrift along the line of the project,the problems of snowdrift in different subgrade sections such as embankment,interchange ramp,cutting and part-cut and part-fill subgrade are selected for simulation.The three-dimensional models are established by Fluent numerical simulation software.The rationality of the model and the reliability of the simulation results are verified by comparing with the actual measurement results.And then,the corresponding snow rules are summarized according to these roadbed forms which are prone to wind and snow disaster.The design suggestions are put forward for the effective prevention and control of snowdrift in similar regions.(3)Based on the formation mechanism of snowdrift,this paper studies the snow prevention effect of snow board and explores the optimization of design parameters of snow board.The wind and snow blocking effects of snow boards with different heights,different porosity and different wind angles are analyzed.The reasonable space layout position of the snow board and the shape of the end of the snow board are proposed,so as to avoid the formation of snow dike on the road and protect the road section with snowdrift effectively.The above results provide reasonable and effective suggestions for the dynamic design and construction of prevention measures of snowdrift,which has important theoretical significance and practical application value to ensure the safe operation of expressway.