Design Wind Force Coefficients for Signboards Installed on the Rooftop of Building

摘要

Recently, rooftop signboards are often damaged and blown off by strong winds. Flying debris resulting from the damage to signboards may cause second damage to other buildings and people. To prevent such damage, an appropriate wind-resistant design should be done to the signboards. In practice, however, wind force coefficients for rooftop signboards are not provided in the codes and standards in Japan. The present paper investigates the characteristics of wind forces acting on the signboards installed on the rooftop of low-rise and middle-rise buildings on the basis of a wind tunnel experiment, in which the shape, size and location of the signboard are varied over a wide range. Special attention is paid to the time-space correlation of net wind forces acting on the signboard. Based on the distribution of peak wind force coefficients, the signboard is divided into several zones, for which the wind force coefficients are specified. The proposed wind force coefficients shall be used for designing the cladding and components of signboards.