Experimental study on wind load characteristics of sloped roof photovoltaic array

Wind load is a critical factor that threatens the structural safety of rooftop PV systems. Experimental tests in a wind tunnel investigated the impact of wind direction and roof slopes ranging from 15° to 60° on the wind loads experienced by PV arrays installed on double-pitched roofs. The results indicate that the entire array experiences wind pressure on the windward side and weaker suction forces on the leeward side. Increasing the roof slope enhances the overall wind pressure on the windward side apparently but does not increase the overall suction on the leeward side. Considering the most unfavorable negative net wind pressures across all wind directions, it was found that increasing the roof slope does not significantly affect the most unfavorable negative mean net wind pressure, but it substantially lowers the most unfavorable negative peak net wind pressure and shifts their occurrence toward the ridge of the roof. The wind pressure recommended in ASCE/SEI 7-22 is conservatively biased, the experimental results for roof slopes larger than 30° show a deviation of 60%–70% from the recommended values in the code.