Resumen
In high demand seasons, heavy traffic causes congestion not only on main carriageways but also in rest areas. Congestion in rest areas make vehicles cruising, crawling, standing and sometimes reverse running inside the area to find a parking lot. Such vehicles form a queue and it may extend out to the main carriageway, which cause more serious congestion. At the same time, it is often observed there are still some available lots left in the back side of the area even though such information is provided. It means drivers do not always behave perfectly and the capacity of the rest area is not fully utilized. Therefore, it is important to understand how drivers make decisions of their behavior to select parking lots under congested situation to improve the performance of the parking capacity. Then, this study aims at revealing drivers? choice behavior of parking lots in expressway rest area. Four rest areas were picked up to collect drivers? choice behaviors considering the characteristics such as geometry, information provision etc. Video observation was conducted to obtain individual vehicles trajectories as well as the transition of the parking lots occupancy. VMS data showing parking lots availability was also gathered to check what kind of information was given when a driver made a choice behavior. At the same time, questionnaire survey was also done to understand drivers? preference, behavioral factors etc. Based on the collected video and questionnaire data, drivers? choice behaviors at diverging points inside the area were analyzed in detail. As a result, major influential factors were revealed to be ?distance to the facilities?, ?availability information on VMS? and ?queue length in sight?. Moreover, the order of their importance was not always the same but varied depending on the condition of the parking lots occupancy. Especially, at near-saturated condition, drivers were affected more by a queue in front rather than VMS information. Finally, some implications for rest area design and operation were shown based on the results.