Title: Level of service on two-way rural roads

Original Title: Razina usluge na dvotračnim izvangradskim cestama

Authors: Boris Čutura

DOI: https://doi.org/10.5592/CO/ZT.2017.19

First page: 39 Last page: 46

Publish date: 18.9.2017 Publish date online: 18.9.2017

Abstract: The level of service (LOS) on two-way rural roads in Bosnia and Herzegovina and neighbouring countries is calculated according to HCM 2010 (Highway Capacity Manual, 2010) methodology. It is defined by measuring efficiency of the average travel speed (ATS) and the percent time spent following in platoon (PTSF). The PTSF parameter is defined as the percentage of time that vehicle drives behind a slower vehicle in platoon. This parameter defines the freedom of manoeuvring and driving comfort, and is related to traffic safety because driving in platoon causes driver nervousness and dangerous behaviour (prohibited overtaking, etc.). That is why the PTSF is the most important measure for the quality of traffic flow. The HCM defines three second headway between the vehicles as a field measure. Many studies have shown significant field deviations compared to calculations according to HCM methodology, as a result of different traffic flow conditions in certain areas, and due to imperfections of the model itself. The paper presents the research conducted so far and goals for defining the model for the calculation of PTSF (level of service).

Sažetak: Razina usluge (eng. Level of Service - LOS) dvotračnih izvangradskih cesta u BiH i susjednim državama računa se prema HCM 2010 (Highway Capacity Manual 2010) metodologiji. Definira se na osnovi mjera efikasnosti prosječne brzine putovanja (eng. Average Travel Speed - ATS) i postotka vremena provedenog u koloni (eng. Percent Time Spent Following - PTSF). Parametar PTSF je definiran kao postotak vremena koje vozilo provede u koloni vozeći se iza sporijeg vozila. Taj parametar određuje slobodu manevriranja i udobnost vožnje i povezan je sa sigurnosti prometa jer vožnja u koloni izaziva nervozu kod vozača i opasno ponašanje (nedopuštena pretjecanja, itd.). Zato je postotak vremena provedenog u koloni PTSF najvažnija mjera u smislu opisa kvalitete odvijanja prometa. HCM je definirao vrijeme slijeda (headway) tri sekunde između vozila, kao mjeru za određivanje na terenu. Mnoga istraživanja su pokazala značajna odstupanja na terenu u odnosu na proračune prema HCM metodologiji, a rezultat su drukčijih uvjeta toka pojedinih područja kao i nedostataka samog modela. U radu su prezentirana dosadašnja istraživanja i ciljevi za definiranje modela proračuna PTSF-a (razine usluge).