Measures of Functional Reliability of Two-Lane Highways

Rural two-lane highways are the most common road type both in Poland and globally. In terms of kilometres, their length is by far greater than that motorways expressways. They roads one carriageway for each direction, which makes overtaking slower vehicles possible only when there a gap stream traffic moving from opposite direction. Motorways express dual carriageways expected to support high speed travel mainly over long distances. Express have somewhat lower technical parameters limit motorways. Two-lane used short- long-distance travel. The paper presents selected studies conducted 2016–2018 on rural focuses context need reliability. research was carried out short longer sections located various surroundings, grouped curvature change rate CCR, longitudinal slopes cross-sections (width lanes shoulders). volumes, time speed, as well density, will be analyze performance identify measures analyzed were characterized good significant variability volume throughout day, week year. Some experience congestion, i.e., situations Q close or above respective capacity C. order determine form suitable reliability measures, it important extent road’s geometric characteristics impact time. well-known proposes new along with an evaluation usefulness assessment functioning highways.