Experimental study on wind load characteristics of rectangular high-rise buildings with varied aspect ratios

Abstract

The wind load is one of the predominant factors for high-rise buildings and it has been found that the aspect ratio of the section affects the wind-induced forces on buildings significantly. In this paper, simultaneous wind pressure tests were conducted for three rectangular tall buildings in the wind tunnel, with different aspect ratios of 1:1, 1.5:1, and 2:1 (named Model I/II/III). The characteristics of wind pressure on buildings under different wind azimuths were analyzed and the following conclusions were obtained. When the longer sides of the buildings (Side I/III) are perpendicular to the wind, the variation tendency of the most unfavorable wind pressure coefficient along increasing aspect ratio has a critical value on the windward/leeward/top facades, and it was found the critical ratio equals 1.5 (Model II). Moreover, when the shorter sides of the buildings (Side II/IV) are perpendicular to the wind, it can be found that Model II presents the most unfavorable wind pressure on the crosswind side. Referring to the leeward side, the larger the aspect ratio, the more favorable the negative pressure appears. Furthermore, the horizontal correlation coefficients at points on the windward/leeward side are generally higher in Model II. The power spectrum of the measuring points on the axis of the crosswind and leeward sides gradually decreases in the low frequency range, while the energy in the high frequency range gradually increases. The comprehensive experimental data provided in this work can be used for further wind resistance studies.