A Full Scale Experimental Study on Assessing Factors of Available Safety Egress Time

全尺寸實驗分析火災避難容許時間的影響因子

王鵬智(Peng-Chih Wang) ； 張尚文(Chang-Shang Wen) ； 林慶元(Ching-Yuan Lin)

《中國機械工程學刊》 28卷5期 (2007/10) Pp. 513-521

https://doi.org/10.29979/JCSME.200710.0006

摘要

避難容許時間為性能式避難設計之評估基準，其檢証結果，直接影響性能式設計成功與否；一般而言，簡易的性能式避難設計檢証法，皆以煙層下降至離地板一定高度為避難容許時間。本研究透過全尺寸實驗，驗證二層煙流模式所預測的煙層下降時間與實際實驗所量測煙層下降時間之關係，以及煙層下降時間與其他相關影響因子達到影響避難極限值時間之比較，以分析計算合理之煙層下降高度。經實驗結果發現：1.經實驗值與預測值比較，一般煙層下降時間趨勢以N=20%最為貼近預測值，建議採用N-percent方式評估時，N值取20%；2.居室火災實驗煙層下降至離地板1.8m的時間與計算式預估之時間大致相同；3.居室火災實驗煙層下降至離地板高度1.8m的時間，與同一實驗煙層所產生的煙粒子濃度、CO量、輻射熱值與溫度值到達臨界值的時間貼近，因此，一般居室以煙層下降至離地板1.8m高度作為居室內人員避難容許時間，尚屬合理。

並列摘要

Available safety egress time (ASET) is the basic essessing criteria in performance-based fire safety design, which will directly determine the success of building design from the results of evaluation. In general, the ASET in performance-based egress design complies with the smoke layer height descending to a certain distance above the floor. Through full scale experiment of compartment fire in this study, we demonstrated that (1) the relationships between the predicted descending time of smoke layer by ”Two Zone Model” and the practical descending time of smoke layer by experimental measurements; and (2) the comparisons between the descending time of smoke layer and the threshold values of other correlative influential factors, which serve to analyze and calculate the reasonable descending smoke layer height in egress design. From the experimental results, we also concluded as follows: (1) by comparing the experimental data with the estimated value, the trends of descending time of smoke layer is close to estimated value when N is equal to 20%. When the evaluation is by ”N-Percent Method”, adopting 20% as the N value is suggested. (2) In the compartment fire experiment, the experimental and estimated values of the descending time of smoke layer to 1.8 meter above the floor are approximately the same. (3) In compartment fire experiment, the time of smoke layer descending to 1.8 meter above the floor is close to the time reaching threshold values of smoke particle density, carbon monoxide concentration, heat flux, and temperature produced by the smoke layer within the same experiments.

並列關鍵字

full scale experiment ； ASET ； performance-based design