Influence of Road Cross Section on Access Spacing

• Authored by:  Dr. Karen Dixon
• Co-authored by:  Dr. James L. Gattis

Dixon, K. and J. Gattis, Influence of Road Cross Section on Access Spacing, Transportation Research Board of the National Academies, Washington, D.C., Oregon Transportation Research and Education Consortium (in progress)

      The primary goal of this proposed research is to better understand how driveway spacing and the associated roadway cross sectional features influence safety and operations. Since the separation of conflict points will generally improve safety, it is critical that the transportation industry understand how to balance access spacing decisions that accommodate the needs of the adjacent land use while also enhancing safety.

            This proposed research effort, therefore, will be an initial effort to identify how drivers react to the increased workload demands when navigating a corridor with a variety of driveways and physical characteristics. To date, little research has focused on quantifying the various conflicts at driveway locations. This lack of research has been due to a number of data collection limitations.  There are numerous combinations of road features that may influence assess spacing and identifying and studying these configurations is an onerous task. This research effort, therefore, proposes using a driving simulator supplemented with field analysis to try to identify critical cross sectional elements that must be included in consideration of access spacing decisions. The research team intends to use the outcomes of this research effort and incorporate any substantive findings into the NCHRP Project 03-99 AMAG.