市區公車之既有路線調整與新闢路線規劃程序之研究

Abstract

現今公車路線之選定與場站的設置，常常僅依憑著決策者的主觀判斷與民意代表或使用者之要求，以致整體路網在缺乏科學方法與理論基礎之規劃下，不僅無法有助於上述市區交通問題的改善，同時更造成系統營運效率與服務水準的低落。有鑑於此，基於公平及效率的考量下，發展一套包含公車既有路線調整與新闢路線規劃準則及規劃程序建立之方法，實為公車業者及政府所迫切需要的。 於公車路網現況評估模式構建中，考量經營者、使用者及管制者等三個層面，並以選取可以量化之指標和避免各指標間具相依性之原則，選取路網密度、涵蓋路線、路線彎繞度、路線直接性、載客量、路網可及性及服務範圍指標為評估路網現況之指標，配合TransCAD及EXCEL之應用，以評估路線調整或規劃增設前後之績效。 在既有公車路線調整方面，分析既有路線調整之影響因素、目標及原則，選取「路線彎繞度指標」及「路線重複性」作為既有路線調整準則。並參考過去相關研究，訂定超過門檻值（1.3＜路線彎繞度＜1.6）或路線重複性高的路線，列為優先考量調整的路線。 考量新闢路線規劃方面，提出新闢路線規劃目標，並進一步分析新闢路線選取原則，且以「交通分區可及性」及「供需比」作為選取亟需規劃新路線之交通分區的準則。結合「TransCAD」之應用，作為公車路網規劃與設計之主要工具。 以台中市市區公車系統為實例分析對象，經既有路線調整準則及新闢路線選取準則之分析，規劃四條調整及合併路線和十三條新闢路線。並選取方案乙（89年先改善調整之路線及99年預估績效值達A級之新闢路線）作為路網改善之方案。

At present, the determination of bus routes and bus terminals are often based on the subjective judgment of decision-makers and requests of legislators or users. The overall planning of the routes network, which lacks scientific method and theoretical basis, not only fails to improve city traffic, but also reduces the system operating efficiency and service level. In view of this, based on consideration of fairness and efficiency, developing planning rules and procedures to adjust existing routes, and establish new routes, is urgently needed for bus operators and government. The operator, user and regulator are considered in the construction of an evaluation model for the existing bus-route network. Based on the principles of selecting quantifiable indicators and avoiding dependency between indicators, such as density of network, routes covered, circuity, directness, occupancy, accessibility of network and coverage of network are selected to evaluate current network. The application of TransCAD and Excel also serves to evaluate performance before and after adjusting existing routes or planning new routes. In terms of adjusting existing bus routes, affecting factors, planning objectives and principles for adjusting existing routes are analyzed, and indicators of “circuity” and “repetitiousness” are selected as adjustment criteria of existing routes. Routes that exceed threshold values(1.3<circuity<1.6) or have high repetitiousness are considered as priority when adjusting routes. In addition, objectives for planning new routes are proposed and principles for selecting new routes are further analyzed. Traffic zoning guidelines such as “accessibility of traffic zones” and “supply-demand ratio” are used for new routes, which are urgently needed. TransCAD application is also the major tool for planning and designing bus-route network. Based on the case study of the city bus system in Taichung City, and analysis of guidelines for adjusting existing routes and selecting new routes, four routes are adjusted and merged and thirteen new routes are established.