Giuseppe Marinelli

Identification of Horizontal Circular Arc from Spatial Data Sources

AbstractCurves represent the most interesting element to be analyzed when evaluating the operational and safety effects of road geometrics. Despite the existence of several static and dynamic survey techniques, the correct identification of curves and the interpretation of spatial data from horizontal road alignment surveys still present a challenge. This paper presents the results of an investigation into the effects of both accuracy and sampling frequency (i.e., the interval between data points) of alignment spatial data on the identification of the radius and center of curvature. In pursuit of this objective, the authors adopted an original approach consisting of the generation of dispersed spatial data points from circular arcs with known characteristics. The least-squares, Huber, and Landau methods were used to back-calculate the radius and the coordinates of the center of curvature and to assess the effects of accuracy and interval between data points. The results obtained quantified the effects of ...

The effect of highway geometry on fuel consumption of heavy-duty vehicles operating in eco-driving mode

This paper presents an analysis of the effects of the geometry of a highway on fuel consumption of heavy-duty vehicles operating in eco-driving mode. Field data from a high traffic volume highway in Norway are used in this study. Vertical and horizontal profile layers of the same road sections are considered individually and merged with vehicle field data. The study includes a correlation and regression analysis to investigate the relationship between the road gradient and the rate of fuel consumption of a representative truck. The effect of road gradient is examined in both acceleration and deceleration (retardation) mode. Different models are devel-oped, which can serve as a tool for decision making at early design and planning phases of a highway project, where information on fuel consumption and its environmental impacts may influence design choices.