公路路網之脆弱度、回復力及減輕對策之資源配置

Abstract

社會進步與人口成長使運輸路網日愈繁雜，社經活動更有賴運輸系統連結，路網中斷將導致用路人旅行成本與旅行時間增加，甚至被迫取消旅次，造成直接災損與間接社會經濟損失甚鉅。造成路網失效的主要原因可概分為自然危害與人為災害，尤其在全球氣候變遷影響下，自然危害致災的機率因強度與延時之提升而大幅增加，因此，運輸路網系統因應災害之能力成為都會地區發展之關鍵課題。 雖然過去文獻不乏脆弱度相關研究，然多基於都市防災觀念及工程導向以界定脆弱度，鮮少針對路網脆弱度與回復力之定義、影響因子與相關衝擊進行探討。故本研究以系統工程方法解構脆弱度與回復力之功能與內涵，據以建立路網脆弱度與回復力模式，並利用系統動態模型協助決策者了解都會區公路路網系統行為，以界定脆弱度與回復力之關鍵影響因子。本研究以台北地區之地震及水災為例，引入模糊集合概念反映外部環境之不確定性，建構防災與復原階段資源配置模式，以敏感度與情境分析說明改善公路路網脆弱度與回復力之相關政策意涵，最終依據分析結果研擬相關策略方案建議，以提供公部門進行資源配置與運輸系統風險評估之參考。

Transportation networks have become more complicated because of social progress and population growth. Numerous socio-economic activities are linked to transportation networks and systems. The network failure will increase the travel time and travel cost of users and even force users to cancel their trips. The network failure results in considerable direct damage as well as indirect socio-economic losses. The main reasons causing network failure include natural hazard and man-made hazard. Particularly along with the global climate change, the probabilities of natural disasters increase remarkably because of the incremental magnitude and duration. The coping capacities of transportation network thus become a critical issue in metropolitan area development. Previous literature discussed the determination of vulnerable infrastructures based on the concepts of engineering-oriented urban disaster prevention. However, the definitions, influencing factors and causalities of vulnerability and resilience are absent. The system engineering method is employed to deconstruct the functions and components and to integrate a network and resilience model. Moreover, a systematic simulation approach is utilized to assist decision-makers in understanding the system behavior of urban highway network and identifying the crucial influence factors of network vulnerability and resilience. The Taipei metropolitan area is applied as an empirical study under the threat from earthquake and flood. Fuzzy set is introduced to reflect the uncertainty about external environment and to construct resource allocation models in stages of disaster prevention and recovery, respectively. Sensitivity and scenario analyses are used to explore the policy implications for the improvement of network vulnerability and resilience. Consequently, the suggested strategies are provided for resource allocation and risk assessment of transportation network according to the analytical results.