| Summary: | 碩士 === 中華科技大學 === 土木防災與管理碩士班 === 101 === Through analyzing the fires in business districts at home and abroad, the main causes include that the commodities there outspread from arcade to street center, which results in negative effects such as spoiling the urban appearances and hampering the flow of traffic, etc., and even causes severe personal injuries and property damages due to the difficulty in escaping caused by inflammables being stacked disorderly to block the escape channels when fire occurred. In view of that, many potential problems of urban disaster prevention are derived. The buildings located on Raohe Street Night Market are joined together and old while the materials used for shacks are inflammable. Besides, the merchants often place large amount of stuff which makes the street narrower, the illegal parking blocks the escape channel, disordered wires and gas widely used here; thus if the masses lack the awareness of disaster prevention and fire apparatus settled in these buildings are too old or incomplete, it will be difficult to evacuate people at the night market and then result in heavy casualties once a fire occurs. Based on the concept of “disaster prevention takes priority over disaster relief”, then we can avoid the damages caused by disasters.
This study utilizes Fire Dynamic Simulator (FDS) as the tool to simulate and analyze the different fire scenarios as below: 1) comparing the fire spread situation and heat release rate (HRR) of different commodities; 2) whether commodities placed in arcade would decrease the effectiveness of the fire protection design and stretch the fires ; 3) the influences of automatic sprinkler equipment on the range of a fire disaster in the arcades; 4) how can the residents evacuate and response when a fire occurs. The results show that: 1) in terms of cotton goods, the HRR reaches to 21155KW at the 38.4 second, and the average HRR is 18297KW, while the commodities are made of composite material, the HRR reaches to 23192KW at the 37.8 second, and the average HRR is 22804KW, which has a higher HRR and fire load, thus the fire disaster is much fiercer within the same time. 2) If there are inflammables stacked under the arcade, it takes 41.4 seconds to spread to the neighbor on the right but 55.8 seconds if there are no inflammables stacked. In addition, fire may spread regardless of the commodities stored in the arcade. Nevertheless, the fires still can be suppressed and controlled by planning effective smoke prevention area, and not placing commodities either in front of the store door or the arcade. 3) The maximum HRR at 592 seconds is up to 53131KW when there is no automatic sprinkler equipment installed, while it reaches to 23654 KW at 83 seconds when automatic sprinkler equipment is installed. Therefore, it can be realized that the automatic sprinkler equipment can rapidly lower the fire temperature, effectively suppress the fire disaster and reduce the level of HRR. 4) When the attic door is open, the measured highest temperature is 674.8℃ in the stairway but below 60℃ within the room, thus it is verified that, in case of the fires occur in these similar architectures, residents staying inside with door closed, and waiting for rescue is much safer.
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