Full-scale measurements of peak pressures on a flat roof corner zone of a low-rise building during typhoons

A full-scale moveable instrumented low-rise building has been constructed to monitor the wind velocity field and associated building surface pressures during typhoon landfalls. The major objective of the field study is to further understand typhoon-generated wind characteristics and wind effects on the low-rise building under extreme wind conditions. This paper presents the analysis results of wind characteristics and extreme suction pressure coefficients on a roof corner zone based on the field measured data obtained from the instrumented low-rise building during Typhoon Chanthu. The surface level wind turbulence characteristics such as gust factor, turbulence intensity and integral scale are quantified in different terrain exposures and different portions of the typhoon. Detailed analysis of the mean, peak and standard deviation of pressures measured on a roof corner zone is conducted to investigate the pressure distribution characteristics. Moreover, the effect of spatial and temporal averaging on peak pressures is also discussed. The windward leading edge on the corner was consistently subjected to the most severe suction pressures and fluctuation pressures for quartering winds. The measured extreme suction pressure was -4240Pa and the minimum negative peak pressure coefficient was -13.5. The probability distribution of the normalized fluctuating pressure coefficient on the corner zone in conical vortex flow regions is non-Gaussian. The effects of large turbulence scale and turbulence intensity on the roof pressures are evaluated for conical vortex flow regime in oblique direction. The extreme value analysis is performed using an automated procedure to determine the peak suction pressure coefficients. The estimated extreme peak pressures are compared with those stipulated by the ASCE 7-10 Standard. The observed and estimated suction pressure coefficients on the windward leading edge on the corner area exceeded the values recommended by ASCE 7-10 Standard.