CHARACTERISTICS OF SNOWDRIFT AND PREVENTION MEASURES IN YULTUZ BASIN

Snowdrift refers to the two-phase flow in which snow particles disperse by airflow and move close to the ground. The proposed Yining-Aksu Railway traverses Yultuz Basin,where is cold with significant snowfall in the winter and spring. Snowdrift disasters are prevalent in this area and pose a threat to the safety of transportation engineering. In this paper,the characteristics of snow accumulation and snowdrift in Yultuz Basin of the Tian Shan region,Xinjiang are analyzed through the field investigation and in-situ monitoring. Considering the Aerxian section of the proposed railway will be significantly affected by snowdrift,this section is taken as an example to analyze the origin of snowdrift and design of preventive measures. The results indicate the disaster-inducing conditions of snowdrift in Yultuz Basin are mainly influenced by the cold snap from Siberian and high atmospheric pressure system in Mongolian. Cold air induces strong northwester wind in the basin. The snow can be kept in a low-density state in low temperatures and humidity condition and evolves into snowdrift at relative low wind speed. Based on the numerical analysis of the typical road cut section in the Aerxian section of this railway,it is suggest that the snow platform width should be set to 5 meters. The angle between the lower deflector plate and the horizontal plane is 90°,while the height of the lower deflector opening is 1.6 meters,and the height of the lower deflector plate is 5 meters. It is expected to provide reference for disaster prevention and reduction of transportation construction in cold regions.