短延時強降雨下道路積淹水評估與原因分析－以臺北都會區為例

CAUSAL ANALYSIS OF ROAD FLOODING UNDER SHORT-DURATION EXTREME RAINFALLS IN TAIPEI METROPOLIS

王嘉和(Chia-Ho Wang) ； 游翔麟(Hsiang-Lin Yu) ； 王嘉瑜(Jia-Yu Wang) ； 張倉榮(Tsang-Jung Chang)

《中國土木水利工程學刊》 35卷6期 (2023/10) Pp. 575-586

https://doi.org/10.6652/JoCICHE.202310_35(6).0005

摘要

都市化發展、都市熱島效應以及氣候暖化造成短延時可降水量增加，此些原因均會增加都市排水系統壓力；而都市排水由進水口、側溝、連接管、下水道、區域排水等元素所組成，各元素會依據集流時間、面積大小而有所不同。近年來，都市地區因短延時強降雨而導致的短暫積淹水頻繁發生，其短時間內之逕流量超過排水能力造成積淹水。對此，本研究對臺北市公館商圈周邊進行分析，分析結果發現當降雨強度大於每10分鐘18.33毫米時，就會有街道積水發生，此降雨強度約為側溝、連接管設計標準的75%，而當暴雨大於此降雨強度後，其強度越大，積水面積也越大。

關鍵字

排水設計 ； 街道淹水 ； 都市淹水 ； 短延時強降雨

並列摘要

In Taiwan, urbanization has led to an increase in impermeable pavements, which subsequently causes the urban heat island effect and aggravates the influences of global warming. Hence, the frequency of the short-duration precipitations is increased such that the loadings of the urban drainage system become more intense. The urban drainage system consists of several key elements, i.e., drainage inlets of gully systems, gully systems, connected pipes between gully and sewer systems, sewer systems including pumping stations, and other regional drainage systems, etc. Each element varies according to the concentration time and size of its drainage area. Recently, more and more short-term inundations happen due to short-duration heavy rainfalls, which dumped massive rainfall in a very short period such that road flooding occurs because the inlets and connected pipes of the drainage systems are unable to handle the resulting excessive runoffs. To discover such a cause of road flooding in urban areas, the present study adopts the National Taiwan University Cellular Automata Rapid Flooding Model (NTU-CAFIM) to assess the causes of road flooding in the Gongguan business district in Taipei city. From the simulated results, there are inundations once the rainfall intensity exceeds a rainfall intensity threshold of 18.33 mm/10 minutes, which is about 75% of the standard drainage capacities of a gully system or a connected pipe. When the rainfall intensity of a rainstorm is greater than the derived threshold, the area of inundation is proportional to the rainfall intensity.

並列關鍵字

drainage design ； road flooding ； urban flooding ； short-duration intense rainfall

參考文獻

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