Equivalent Static Wind Loads on Plate-Like Flat Roofs: Data-Based Closed Form

Abstract

Wind tunnel pressure tests on flat-roof buildings were carried out for three kinds of length-width ratio models in three types of terrain. Based on the fitted generalized force spectrum, the analytical expression of equivalent static wind load (ESWL) on plate-like flat roofs was derived using the inertial force method, which is expressed as a function of the structural reduced frequency. The results show that wind directions along the short building side and the long building side are the two most unfavorable wind directions in the view of nodal displacement and member stress; terrain type has important effects on the coefficient of ESWL, increasing the turbulence intensity enlarges the coefficient of ESWL, and it decreases with increases in the reduced frequency. The nodal displacement and member stress calculated by the proposed analytical formula agree well with the actual peak response in two unfavorable wind directions, and the response agreement in the wind direction along the building long side is poor using the gust loading factor method.