Investigation On Application Of Snow-fence In Controlling Road Snow Drifting Disaster

The snow drifting disaster on road is a natural phenomenon in which snow particles deposit on the road when snowdrift flows through the road.Its influence can be mainly divided into dynamic obstruction to vision and static snow accumulation on the road.Some measures need to be taken to reduce the impact of snow drifting disaster on the road,since the economic and property losses every year arise from snowdrift cannot be ignored.The prevention measures of snow drifting disaster on the road can be divided into active and passive types.And snow-fence,one of the most common used passive controlling measures,is widely used in the prevention of snow drifting disasters on the road which can adapt different snow drifting environments by changing parameters and settings.In this paper,the methods combining wind tunnel test,field observation and numerical simulation are used to study the anti-snow effect of snow fence with different parameters which aims to provide a reference for the setting of snow fence in blowing snow conditions.This paper mainly conducts the following work:(1)The wind tunnel test was adopted to study the influence of the height,porosity of snow fence and wind speed on the distribution of snow around snow fence.The results showed that as the porosity,height of snow fence and test wind velocity increase,the position of accumulated snow will move downstream and the range of accumulated snow on the leeward side of snow fence will increase.The snow fence in 60% porosity and with larger height has a better snow block effect.(2)Field observation on snow fence with 15 cm height and 60% porosity was conducted to investigate the evolution of accumulated snow around it.The results show that the range and thickness of snow cover on the leeward of snow fence increase with time.The position of the maximum snow cover thickness is at around 7～8 snow-fence height on the leeward side and the maximum range of snow cover is 28 snow-fence height.(3)Numerical simulation method was used to study the distribution of flow field around the snow fence with different parameters and different snow accumulation shapes.The snow formation mechanism around the snow fence was analyzed.And the snow morphology obtained from wind tunnel tests and field observation was added to the numerical model.The influence of snow cover on the flow field around snow fence was studied.The results show that the development trend of snow cover can be predicted according to the flow field around snow fence.So that the snow formation mechanism around the snow fence can be qualitatively described.The existence of snow cover will change the flow field around the snow fence and affect the surrounding snow morphology.