Operating speed models of two-lane rural state roads developed on continuous speed data

Preliminary communicationThis paper presents models for predicting operating speeds on tangent sections and curves of two-lane rural roads developed on continuous speed data.The data corresponds to 20 drivers of different ages and driving experiences, driving their own cars along an 18 km long section of a state road.The data were first used for determination of minimum operating speeds on curves and maximum operating speeds on tangents and their comparison with speeds in the middle of curves and tangents i.e. speed data used in most of the operating speed studies.There was no significant difference between speed models developed using speed data in the middle of tangents and curves and models developed using maximum and minimum operating speeds on tangents and curves.Models developed on continuous data have higher coefficient of determination than models developed on spot speed data.It can be concluded that the method of measuring has more significant impact on the quality of speed model than the location of measurement.