Wind Loads on Overhead Sign Structures: A Comparative Study

Abstract

Road signs are prone to extreme winds that cause significant damage. Overhead sign structures can disrupt traffic and cause harm to the traveling public if a failure occurs under extreme wind conditions. In this paper, we employ Computational Fluid Dynamics (CFD) in a comparative study to understand the aerodynamics of standard, porous, and curved signs. The study shows the viability of porous and curved overhead boards for lessening aerodynamic loads, which can mini-mize damage and enhance safety on roadways. Porous overhead signs can decrease the drag forces; however, the size of the openings is a vital parameter in reducing wind loads. Small and uniform perforations lead to higher drag forces, compared to larger ones, under the same porosity ratio. Introducing porosity to a solid panel moves the vorticity region further downstream, reducing the magnitude of pressures on the leeward side and decreasing the drag force. However, curved panels further enhanced the force reduction.

Keywords

• wind loads
• overhead structures
• CFD
• aerodynamics
• bluff body