UC Berkeley

Long bus queues can form at a busy bus stop where multiple routes converge. These queues and the delays that they impart to buses can often be mitigated by altering the stop's design or the manner in which it is operated. Queueing models are formulated to this end. The models estimate the maximum rates that buses can discharge from a stop that is isolated from other stops and from nearby traffic signals, while maintaining targets for service quality. Model inputs include the stop's number of serial berths, and the processes by which buses arrive and dwell at the stop. The models can be used for a variety of purposes that include: choosing a stop's suitable number of berths or determining when it is useful to alter the rules governing how buses are to dwell in those stops. Application of these models indicates that much of the previous literature on the subject of bus queueing at stops is flawed. And because the analytical solutions derived for the present models describe the special operating features of serial bus berths, the models can be applied to other serial queueing systems common in transport. These include taxi queues, Personal Rapid Transit systems and toll plazas with tandem service booths.