考量旅次特性與停車指派之自行車容受力估計：以國立臺灣大學為例

Abstract

自行車作為便利、輕量、低成本且環境友善的短途交通運輸工具之一，近年來逐漸受到重視與推廣。許多城市開始建設、導入自行車相關的軟硬體設施，如自行車道、自行車停車位、共享自行車系統等。然而，當自行車使用量增加，相應的停車問題也會隨之出現；若停車供給不足以負荷需求，一則可能出現違規停車，對城市空間造成影響，二則可能減少民眾騎乘自行車之意願。公共自行車系統雖可緩解停車現象，但也有其可週轉之上限。

本研究以容受力之概念出發，使用最佳化模型，以供給面角度建立一套由自行車停車位與旅次分布推估自行車最大使用量之研究方法，並納入共享自行車的供給，探討對整體系統之影響。本研究以國立臺灣大學校總區做為案例，基於晨峰、午峰、昏峰的交通流量進行停車分配與推估自行車容受力，並探討其在不同情境下之變化，包含旅次總量、可接受步行或停車距離、共享單車投放車輛數、停車空間與分布等。

本研究之結果顯示，在同一區域中，自行車的容受力容易受到旅次特性之影響，旅次分布愈平均，所可容納之自行車使用量愈大。共享自行車能夠有效增加自行車之容受力，惟其投放車輛數與調度須達到一定效益。使用者對步行距離的接受度將會是決定停車容受力的一大因素。儘管本研究之分配模型與實際停車分布不見得相同，模型結果依舊可以做為改善自行車停車設施的參考。本研究最後提出考量旅次特性下的自行車設施規劃建議，並指出未來可行的研究方向，期能使未來相關單位對於自行車設施的規劃與檢討有更系統性的方法，確保不會因為供給不足而產生對都市環境的外部成本。

As a convenient, lightweight, low-cost, and environmentally friendly mode of short-distance transportation, bicycles have gained increasing attention and promotion in recent years. Many cities have begun to develop and implement various bicycle-related infrastructure projects and services, such as bike lanes, parking facilities, and bike-sharing systems. However, as bicycle usage increases, parking issues have emerged. An insufficient parking supply can lead to illegal parking, which disrupts urban spaces or discourages cycling due to inconvenience. While public bike-sharing systems can alleviate parking pressure, they also have limitations in terms of turnover capacity.

This study adopts the concept of “carrying capacity” and develops a supply-oriented optimization model to estimate maximum bicycle usage based on the spatial distribution of parking supply and trip patterns. The model also incorporates the supply of shared bicycles to evaluate their impact on the overall system. Using the main campus of National Taiwan University (NTU) as a case study, this research analyzes the parking allocation and bicycle carrying capacity during morning, noon, and evening peak hours under various scenarios, including changes in total trip volume, acceptable walking and parking distances, shared bike fleet size, and parking space configuration.

The results indicate that within a fixed area, bicycle carrying capacity is significantly influenced by trip characteristics; more evenly distributed trips allow for a greater number of bicycle users. Shared bicycles can effectively increase carrying capacity, provided there is an adequate fleet size and operational turnover. Users’ tolerance for walking distance is also a key factor in determining parking capacity. Although the model’s allocation results may differ from actual parking behavior, they still offer valuable insights for improving bicycle parking facilities. This study concludes by offering recommendations for bicycle infrastructure planning based on trip characteristics and outlines future research directions. It aims to provide relevant authorities with a more systematic approach to planning and reviewing bicycle facilities, ensuring that an insufficient supply does not result in negative externalities for the urban environment.