Fatigue of tubular steel lighting columns under wind load

Lighting and traffic signal columns are mainly stressed by excitation due to natural, gusty wind. Such columns typically have a door opening about 60 cm above ground level for the connection of the buried cable with the column's electric system. When the columns around this notch are inadequately designed, vibrations due to gusty winds will produce considerable stress amplitudes in this area, which lead to fatigue cracks. To give a realistic basis for a reliable and economic design of lighting and traffic signal columns, a number of experimental and theoretical investigations have been made. The proposed design concept allows the life of such columns to be assessed with a satisfactory degree of accuracy.