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Wind loading is the most dominant load for light-weight structures such as membrane roofs. Since the multi-bay horn-shaped membrane roof has a complicated shape and is composed of several horn-units depending on the building type, basic data for the wind-force coefficient has not been reported yet. On the other hand, the multi-bay horn-shaped membrane roof is usually designed using the structural behavior of a one-unit system. Furthermore, the authors consider that the design method must be changed not only according to size and building type but also supporting systems. From the view of these problems, in this paper, the wind-force coefficients for design and analysis are clarified by the wind-tunnel test, and a design method considering the influence of supporting systems under wind loading is proposed.

The authors reported previously that a possible beneficial effect for lenticular pneumatic structures can be obtained by not controlling internal air-pressure but instead setting an appropriate initial internal air-pressure which prevents the membrane structure from becoming unstable under strong winds. The principal aim of this study was to develop a method of setting this internal air-pressure. Firstly, dynamic data was collected through wind tunnel tests using both a rigid and a flexible model for the purpose of understanding the wind pressure coefficient under strong winds and the dynamic behavior of fluctuating internal air-pressure. Next, a time-history wind response analysis was performed to evaluate the fluctuating internal air-pressure under strong winds, and then compared with the results of flexible model by the wind tunnel test. Finally, a methodology for setting the internal air-pressure was proposed based on the data obtained from the static and the dynamic numerical analysis.

Wind load is the most dominant load for lightweight structures such as membrane roofs. Particularly since the horn-shaped (conic) membrane roof has a complicated shape, the basic data for the design wind load on the horn-shaped membrane roof has not been reported. In this paper, the authors focus on the wind-load on one-unit horn-shaped membrane roof with rise-span ratio of 0.2, and report wind tunnel tests for it. From these tests, the wind pressure coefficient, fluctuating wind pressure coefficient and peak wind pressure coefficient are provided under the natural wind of terrain. In addition, the comparison between static response analyses and dynamic response analyses using the result of wind tunnel test indicates the gust factor based on stress of the membrane.

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