Warrants and Recommendations on Using Temporary Work Zone Signs in High Wind Areas

摘要

Under high wind, temporary traffic signs in a work zone are possibly being knocked down, which is a safety threat to through traffic, and is one of major contributors of work zone related incidents. In this paper, traffic engineers' opinions in the performance and application of mostly used temporary traffic signs were collected, followed by the field observations in the state of Texas, USA, and wind effect simulation on temporary traffic signs through finite element analysis. Previous cost-benefit analyses of temporary sign applications were reviewed, and warrants of the applications in work zones with high wind were recommended. Field observations suggest that, embedding signs performed better than skid signs in work zones when high winds are in presence. For the finite element analysis, four important factors were employed to evaluate the performance of each temporary sign, such as: (1) minimum safety factor, (2) maximum stress distribution, (3) maximum displacement, and (4) deviation angle. It was concluded that, for areas with strongly higher wind, the embedding traffic signs are mandatorily recommended like the dual leg perforated square metal tubing with anchor sign and its updated versions, while skid signs are not recommended. In areas with moderate strong wind during certain specific months, the embedding signs are highly recommended, while skid signs shall be limited for use, including: (a) the independent dual upright with leg PSST skid sign, and (b) the dual leg PSST skid support sign. For light wind area and relevant time periods, both embedding signs and skid signs can be safely used. Wooden signs, such as the wooden skid with two wooden legs sign, and wooden long/intermediate-term single leg (H-leg) sign, are also alternative options.