Experimental investigation of wind-induced internal pressures in nominally sealed building structures

Abstract

The action of internal pressure cannot be neglected in wind-resistant design of large-span structures, high-rise buildings, and low-rise residential buildings. In this study, the internal pressure characteristics were first measured in still air in a completely closed building structure without any leakage. Then a series of wind tunnel tests were conducted to study the probability density distribution characteristics of the internal pressure responses in a nominally sealed building with background leakage. The mean and peak internal pressure responses associated with different background leakage distributions and wind directions were further investigated, and the experimental results were compared with those suggested by the Chinese wind load code GB50009-2012. The results indicated that the internal pressure in the completely closed building was non-stationary, and varied significantly when collected at different time points. Furthermore, a period of about 24 h was observed from the measured time history of internal pressure over 9 d. The internal pressure in a nominally sealed building structure nearly fitted a normal Gaussian distribution. When background leakage was uniformly arranged on the surface of the building, the mean internal pressure coefficient remained unchanged with increasing background leakage, varying within the range from −0.15 to −0.14, indicating lower magnitudes than the value of −0.2 suggested by the Chinese wind load code. The minimum negative peak internal pressure coefficient was −0.255 when the peak factor was 3.5, indicating a lower magnitude than the value of −0.326 calculated in the Chinese wind load code.