臺北市颱洪與坡地災害潛勢界定與風險分析

DETERMINISTIC AND PROBABILISTIC HAZARD ANALYSES OF TYPHOON-INDUCED DISASTERS IN TAIPEI CITY

楊國鑫(Kuo-Hsin Yang) ； 周瑞生(Jui-Sheng Chou) ； 鄭明淵(Min-Yuan Cheng) ； 涂莞庭(Wan-Ting Tu) ； 雷泰雄(Tai-Xiong Lei) ； 蔡茂岳(Mau-Yue Tsai)

《營建管理季刊》 86期 (2011/06) Pp. 59-73

https://doi.org/10.6505/CMJ-2011-86-59-15

摘要

臺灣都會地區由於受氣候及地形之影響，易因颱風或豪雨而造成災害，進而威脅人民生命及財產，故了解災害可能發生的潛勢為所有災害預防與應變之首要工作，並可作為日後防災地圖、逃生避難路線、收容安置物資與空間規劃之依據。本研究考量災害發生之頻率及其對臺北市整體影響之重要性與威脅性，擬定颱洪及坡地災害潛勢為主要分析與研究對象。本文首先介紹現行臺北市各地區淹水潛勢、土石流潛勢溪流與老舊聚落內坡地崩動潛勢之學理界定準則。利用此準則，以臺北市士林區為例，分別針對每24小時延時不同降雨量之情況，進行颱洪及坡地災害之定量風險分析(deterministic hazard analysis)與機率風險分析(probabilistic hazard analysis)。在定量風險分析中，本研究探討該區於不同降雨量下受影響之人口數；在機率風險分析中，建立受影響人口數與可能發生的重現期距(return period)或年超越機率的關係(probability of exceedance)，依此關係繪製成之危害度曲線圖(hazard curve)。研究的結果可作為都會區防災整備(disaster preparedness)與救援規劃(rescue planning)的決策資訊。最後，本文將模擬結果針對該區之救災物資與收容空間進行比較與討論。

關鍵字

都會區複合災害 ； 災害潛勢界定 ； 風險分析 ； 淹水潛勢 ； 土石流潛勢溪流 ； 老舊聚落內坡地崩動潛勢

並列摘要

Due to the extremely global climate change, many natural disasters cause damage and threaten people's lives and properties. Therefore, the works to prevent and response disaster are very important and, among which, the prediction of the disaster potentials is challenging. Identifying the potential disasters in the surrounding environment early on can serve to make disaster mitigation maps, arrange resident evacuation routes, and plan supplies and shelters. This study firstly presents the conventional methods used to determine the typhoon-induced disaster potentials in Taipei City, including flood, debris flow and landslide in the aged communities. A deterministic hazard analysis is thus performed based on the disaster potentials. The impact of heavy rainfall with various precipitation intensities on the affected population in the Shihlin District is illustrated as a case study. Further, a probabilistic hazard analysis is conducted to establish hazard curves which are the relationships between the affected population and the return period or the probability of exceedance. Lastly, the analytical results are compared to the current capacity of rescue supplies and civilian shelters in the Shihlin District. This study offers decisive information for the disaster preparedness and rescue planning. The findings from the deterministic and probabilistic hazard analyses are then discussed to bring this paper to an end.

並列關鍵字

Disaster potentials ； Hazard analysis ； Deterministic and probabilistic approach ； Urban flood ； Debris flow ； Landslide in the aged community