Travel time measurement in closed toll highways F. Soriguera a,b, * , D. Rosas a,1 , F. Robusté a,b,2 a CENIT – Center for Innovation in Transport, Technical University of Catalonia (UPC), Jordi Girona 29, 2-A, 08034 Barcelona, Spain b School of Civil Engineering, Technical University of Catalonia (UPC), Jordi Girona 1-3, B1, 08034 Barcelona, Spain article info Article history: Received 14 September 2008 Received in revised form 12 February 2010 Accepted 12 February 2010 Keywords: Highway travel time measurement Toll highways Toll ticket data abstract Travel time for a road trip is a drivers’ most appreciated traffic information. Measuring tra- vel times on a real time basis is also a perfect indicator of the level of service in a road link, and therefore is a useful measurement for traffic managers in order to improve traffic oper- ations on the network. In conclusion, accurate travel time measurement is one of the key factors in traffic management systems. This paper presents a new approach for measuring travel times on closed toll highways using the existing surveillance infrastructure. In a closed toll system, where toll plazas are located on the on/off-ramps and each vehicle is charged a particular fee depending on its origin and destination, the data used for toll collection can also be valuable for measuring mainline travel times on the highway. The proposed method allows estimating mainline travel times on single sections of highway (defined as a section between two neighboring ramps) using itineraries covering different origin–destinations. The method provides trip time estimations without investing in any kind of infrastructure or technology. This over- comes some of the limitations of other methods, like the information delay and the excess in the travel time estimation due to the accumulation of exit times (i.e. the time required to travel along the exit link plus the time required to pay the fee at the toll gate). The results obtained in a pilot test on the AP-7 toll highway, near Barcelona in Spain, show that the developed methodology is sound. Ó 2010 Elsevier Ltd. All rights reserved. 1. Introduction There is common agreement among drivers, transportation researchers and highway administrations that travel time is the most useful information to support trip decisions (users) and to assess the operational management of the network (administrators) (Palen, 1997). In response to these needs for accurate road travel time information, researchers and practitioners from all over the world have worked hard in this direction. During the last two decades, research efforts have been focused on the indirect estima- tion of road travel times, using the fundamental traffic variables, primarily each vehicle’s speed observed at discrete points in the freeway. The prominence of this approach results from the fact that, for ages, these have been the unique available traffic data, as provided by inductance loop detectors. Advances in this research area have been huge as it demonstrates a vast re- lated literature. The efforts made in improving the accuracy of speed estimations from single loop detectors should be emphasized (Coifman, 2001; Dailey, 1999; Mikhalkin et al., 1972; Pushkar et al., 1994). However, although accurate spot speed estimations have been obtained (as in the case of using double loop detectors), travel time estimates could still be 0191-2615/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.trb.2010.02.010 * Corresponding author. Address: CENIT – Center for Innovation in Transport, Technical University of Catalonia (UPC), Jordi Girona 29, 2-A, 08034 Barcelona, Spain. Tel.: +34 934137667; fax: +34 934137675. E-mail addresses: francesc.soriguera@upc.edu (F. Soriguera), dulce.rosas@upc.edu (D. Rosas), f.robuste@upc.edu (F. Robusté). 1 Tel.: +34 934137667; fax: +34 934137675. 2 Tel.: +34 934017104; fax: +34 934017264. Transportation Research Part B 44 (2010) 1242–1267 Contents lists available at ScienceDirect Transportation Research Part B journal homepage: www.elsevier.com/locate/trb