相鄰拱形屋頂廠房建築物對其風荷載影響之研究

A Study on the Wind Loadings of the Arched Roof Industrial Building under the Shielding Effect by Neighboring Building

本研究取用不同拱高與跨度比的拱形屋頂建物模型，運用同步量測技術，獲得表面風壓資料，同時考慮建築群的遮蔽效應，加入上游鄰棟建築物，研究不同配置狀況對於風載重的影響。本研究同時利用相關性積分法探討結構系統的受風反應及推估最大等值靜載重。實驗量測所得的資料並同時與規範相比較，相互驗證。研究結果顯示，低層建築物外表披覆物所受的風壓作用，則以拱高較低緩的屋頂較高，另一方面在上游角隅位置及側風面山牆的上游區均有甚高的尖峰風壓作用，對局部構件設計而言，屋頂角隅及側牆周邊的加強抗風設計有其必要性。在遮蔽效應方面，本研究針對多種拱形屋頂建物模型受到包括順風向前後縱列、橫風向並排、交錯式排列等多種由近到遠的組合，並檢核其產生的最大結構反應與等值靜載重，均無出現明顯增加載重的情況。因此國內規範在此方面未做特別規定，亦屬保守的方式。由實驗成果風壓分佈的情形加以分析及推估載重，低層建築物受上游建築物遮蔽作用影響，對於主抗風系統的載重而言，屬減抑的效果。對於局部披覆物的風壓作用，則在橫風向相鄰小棟距的條件下，因局部流場加速作用，而產生較嚴重的負壓。

A series of measurements of the surface pressures on arched roof low-rise buildings models with variant rise-to-span ratio were conducted with simultaneous pressure measuring system. The shielding effect of neighboring building were considered in this study, so a dummy model with same shape was put at the upstream of model with variant locations to evaluate the effect. Firstly, the mean, root-mean-square and peak value of wind pressures were surveyed. And with these simultaneous pressures data, the equivalent static wind loads on the structure system were calculated with the LRC method. The results shown, the shielding effect will reduce the surface pressure and the structural loadings, but in the case of small gap between buildings will increase peak pressure at side wall and corners of roof. It is found that the design wind code of Taiwan seems do not suggest different design wind pressures to the single building about the shielding effect for the design wind loads of low-rise buildings. But according to the results of this research, the design results on the structural wind loads still in the safe side.