WIND LOADS ON ROADSIDE SIGNS

THE RESEARCH DOCUMENTED IN THIS REPORT WAS DIRECTED IN GENERAL AT THE DETERMINATION OF THE VALIDITY OF EXISTING WIND LOAD DESIGN CRITERIA FOR HIGHWAY SIGN SUPPORTS AND AT SOUND ECONOMIC METHODS OF ACHIEVING AN OPTIMUM BALANCE BETWEEN WIND LOAD DESIGN REQUIREMENTS AND A SIGN SUPPORT WITH REDUCED MASS. ALTERNATIVE APPROACHES WHICH WERE EXAMINED INCLUDED THE USE OF NON-SOLID SIGN BACKGROUNDS. THE FINDINGS FROM THE RESEARCH INDICATED THAT CURRENT DESIGN CRITERIA FOR WIND LOADS ON HIGHWAY SIGNS ARE REASONABLE EXCEPT THAT THE SIGN SHAPE (ASPECT RATIO) HAS A SIGNIFICANCE WHICH IS IGNORED IN DESIGN. IT WAS ALSO ESTABLISHED THAT REDUCTIONS OF THE ORDER OF 50 PERCENT IN WIND LOAD FORCES CAN BE OBTAINED THROUGH THE USE OF LOUVERED SIGN PANELS. IT WAS ESTABLISHED THAT SIGNIFICANT REDUCTIONS IN THE MASS OF THE SIGN SUPPORT COULD BE OBTAINED WITH A MODERATE INCREASE IN THE RISK OF FAILURE FROM WIND FORCES BY REDUCTIONS IN THE DESIGN WIND RECURRENCE INTERVAL. /BPR/