Study on the Selection of SB-Level Low Wind Resistance Metal Beam-Post Guardrail Structures

Both concrete guardrails and corrugated beam guardrails have certain wind resistance that can easily hinder wind speed in sections with severe wind-blown sand and snow. This can further cause sand and snow particles to accumulate on the road surface, thereby reducing the friction coefficient of the road surface and having adverse effects on the safety of operating road traffic. The study analyzed the formation mechanism of wind-blown sand and snow, analyzed the functional characteristics of guardrail structure, and explored the SB-level low wind resistance metal beam-post guardrail structure from the perspective of reducing wind resistance area and considering the characteristics of protective vehicles. The main conclusions are as follows: (1) In areas with high wind speed and abundant sand and snow, the roadbed guardrail will have a blocking effect on the wind due to its cross-sectional size, causing wind-blown sand and snow on the road surface. The low wind resistance guardrail can be adopted in key areas, and the metal beam-post guardrail type can be adopted. (2) Considering the types of vehicles protected by SB-level guardrails, the guardrail structure adopts the form of upper and lower beams, with the upper beam mainly protecting large vehicles (buses and trucks) and the lower beam protecting cars. (3) The connection type between beams and posts varies depending on the cross-sectional shape of the tube. Considering the low wind resistance characteristics and structural protection capabilities, circular pipe beams with good wind resistance and square pipe beams with better cross-sectional bending resistance can be used as a beam structure. Circular pipe beams are connected to posts using channel-shaped, while square pipe beams are connected to posts using C-shaped connectors.