Study On The Railway Wind Porous Fence Mechanism And Application Technology Of Qinghai Yardang Landform

The desert sand migration has a serious impact on the desert highway,railway and the surrounding ecological environment.In order to effectively prevent and control the migration of sand in the wind,it is necessary to conduct in-depth study of flow field.In practical engineering,PE net is used to control the sand in desert,and the high vertical PE net plays an indispensable role in preventing the spread of sand.Due to the lack of PE net durability,plus Yardang Landform environment,strong ultraviolet radiation,so PE is relatively easy to damage.Also cause serious pollution to the environment and can not be recycled.In view of this,considering the durability and economy problems such as porous fence,the porous fence used in railway desert sand prevention and control engineering,and the cross section characteristics and structure optimization team to carry out research work.Determine the most economical and reasonable section and structure type to meet the engineering requirements.Through the numerical simulation and model test,the main results are as following:(1)By means of numerical simulation and model test on the screen behind the screen below the starting wind speed range,determine the optimum porosity is 20%-30%,the optimal angle is 30°-50°,the butterfly porous fence angle to be better than the sand control effect in the same plane screen opening rate case;(2)The application of porous fence in the desert sand prevention and control,0.3,0.4,0.5 uneven porosity screen at the bottom sediment guiding ability was significantly better than the other section of the porous fence,with the increase of wind speed,the bottom sediment guiding ability,can make the porous fence leave space to reduce porous fence stress,prolong the life of the porous fence;(3)The desert sand control in the sandstorm larger area,the need for a double layer or multilayer protection network can play a better shielding effect.Through the numerical simulation,different height of porous fence simulation,reasonable spacing of double porous fence is about 26h(H is the height of porous fence);(4)When the wind speed is 26.7m/s,to meet the security under the premise of the reinforced concrete column with prismatic cable-stayed type anchor retaining structure,the maximum width of 6m screen,can bring substantial help to reduce the project...