| 摘要: | 建築物在受風擾動下，除安全性上受關注，其使用人員的舒適度在結構設計裡亦是一個重要的議題。對於建築物受風影響造成的振動，其舒適度規範的制定長久以來一直備受爭議，除了身體因素之外，還包括心理、外在因素等眾多影響。台灣目前風力規範訂定之舒適度標準為 5 mm/sec² 加速度，對應之回歸週期為半年。
為建立在地資料以作為未來風力規範改進之參考，本研究使用淡江大學風工程研究中心之振動模擬台，具體執行簡諧振動與真實建築物之隨機振動試驗，獲得問卷調查資料，並據以建立舒適度規範(2%、5%與50%人員發生抱怨百分比)與對應之回歸週期。
由結果得知：
一、舒適度門檻值將隨不同振動頻率而改變 (0.1Hz~1.08Hz)。
二、簡諧振動下處於前後振動方向較處於左右振動方向敏感；隨機振動下
則無顯著方向差異。
三、簡諧振動下振動頻率越高，加速度門檻越低。
四、隨機振動下振動頻率越高，加速度門檻越高。
五、 隨機振動下，振動主頻越低則舒適度門檻受瞬間尖峰振動之影響較大；
振動主頻越高則受整體振動感覺之影響較大。
然而依據本論文之方法求得之回歸週期，無法合理地隨反對百分比增加而增長。原因可能為考慮振動大小之包松分佈不完備所致。未來接續之研究將對此做更好的修正，使回歸週期之決定更合理。
Under wind disturbance, the comfort of occupants in buildings is an important issue in the structural design aside from safety consideration. The human comfort criterion for wind-induced motion has been a long-time controversial issue because many factors, either physiological or psychological, can considerably differentiate the outcome. Recently, a constant criterion of 5 cm/sec2 for a half-year return period was regulated in Taiwan building wind code.
In an attempt to build up the local data base in preparation for improving the building wind code in the future, this research aims to conduct surveys to investigate the comfort criteria by using a motion simulator in the wind engineering research center, Tamkang University. A methodology and feasible procedure to determine the comfort threshold and the return period were proposed in this study. Two types of surveys by using harmonic motion and random motion, respectively, were performed to obtain the comfort thresholds for 2%, 10% and 50% of people objecting and their corresponding return periods.
The survey results indicate that
(1) The comfort thresholds are frequency-dependent in 0.1~1.08 Hz.
(2) Under a harmonic motion, people with body orientation in fore-aft direction are more sensitive to vibration than in side-to-side direction. But this observation does not apply to random motion situation.
(3) Under a harmonic motion, the comfort (acceleration) threshold decreases as the vibration frequency increases.
(4) Under a random motion, the comfort (acceleration) threshold increases as the vibration frequency increases.
(5) Under a random motion, the peak motion effect plays an more important role in comfort when the vibration frequency is lower, while the average motion effect (root-mean-square) is more emphasized in terms of feeling if the vibration frequency is higher.
Unfortunately, it is found that, following the methodology proposed, the return period obtained does not reasonably increase with percentage of people objecting. It might be due to the assumption of Poisson distribution in regard to the vibration, which is worth further investigating in the future studies. |
