Thunderstorm impact on the built environment: A full-scale measurement and post-event damage survey case study

This paper investigates the impact of an intense thunderstorm on the urban area of Sˆannicolau Mare, Romania, based on the meteorological data collected by full-scale field measurement and the damage data of low-rise buildings obtained by post-event survey. The meteorological data throughout the entire thunderstorm process were collected from two sources, namely, a wind and structural monitoring system of a 50 m-tall lattice tower and a state-operated meteorological station, both located at the outskirts of the city. The damage data were collected by post-event in-situ survey with crowdsourcing techniques, providing information of both wind- and hail-induced damage to over 200 low-rise buildings. Based on the meteorological and damage data, the damage mechanisms were revealed by conducting forensic engineering analysis for two representative buildings which respectively sustained severe wind- and hail-induced damage. Moreover, the widely used estimation scales for wind intensities, such as the Fujita scale, were validated by anemometric records and damage observations. Finally, the feasibility of utilizing the hail-induced damage to building facades as a new indicator for the estimation of wind speed and direction was discussed. This study aims to further understand the impact of thunderstorms on low-rise buildings, so as to deliver essential information for their storm-resistant designs.