Power spectra of wind pressures on low building roofs

Wind pressure spectra were measured at various tap locations on the roofs of several low building models placed in two types of terrain in order to determine their characteristic shape and derive a suitable analytical model for their representation. The results show that though spectra vary under different conditions, appropriately normalized spectra are found to be identical in many situations. On this basis, a suitable empirical form has been derived for the synthetic generation of normalized spectra. An attempt has also been made to classify complex spectral patterns, and suggest standard spectral shapes associated with various zones of each roof and their parameters. The synthetically generated pressure spectra can be utilized for the simulation of wind pressure fluctuations on roofs not only for the evaluation of extreme pressures in a risk-consistent way but also for fatigue design purposes.