公路低风阻金属梁柱式护栏阻沙效果研究OACHSSCD

Wind-sand disasters represent a common natural hazard affecting road transportation in Xinjiang.On highways frequently subjected to such events,the traditional W-beam guardrails have been found to significantly exacerbate sand accumulation on the road surface.The metal beam-column guardrail with small windward surface,low wind resistance and small disturbance to the wind-sand flow of the road surface is gradually applied to the expressway in the wind-sand area.However,the mechanisms through which cross-sectional configurations(rectangular or circular tubular rails)and post spacing(3m,4m)affect sand deposition remain poorly understood,which hinders the performance-oriented optimization of sand-control guardrail systems.Through wind tunnel tests and numerical simulation test,this study systematically analyzed the effects of metal beam-post guardrails with different cross-sectional configurations(rectangular tubular rails and circular tubular rails)and post spacing(3m,4m)on wind-blown sand hazards over road surfaces.The results show that the wind-blown sand flow is obstructed by the guardrail,disturbing the near-ground wind field and generating deceleration zones,which leads to sand accumulation on the road surface.Particularly in the central median and downwind areas,the deceleration effect is pronounced,resulting in substantial deposition of sand particles.Furthermore,the accumulated sand subsequently alters the structure of the flow field.The guardrail alters the structure of the wind-blown sand flow and induces energy dissipation in the airflow,thereby reducing its sand-transport capacity and resulting in varying degrees of sand accumulation on the road surface.Compared to the cross-sectional shape of the beam,the post spacing is a critical parameter affecting sand accumulation.When rectangular tubes are used for the beams,increasing the post spacing to 4 meters significantly improves the near-ground flow field structure,thereby mitigating airflow energy loss and reducing sand deposition on the road surface.It is therefore recommended to implement rectangular tubular guardrails with 4 m post spacing in practical applications.The findings of this study can provide valuable references for the optimization design of metal beam-post guardrails to enhance their sand-control efficiency.