Crash Risk and Access Spacing on Two-Lane and Multi-Lane Highways

Hitesh Chawla; Peter T. Savolainen, Ph.D., P.E.

INTRODUCTION

Effective access management is essential to mitigating traffic crash risks. Most of the crashes occurring near access points are a result of conflicts between multiple vehicles. This motivates the development of guidelines for access spacing. To this end, this study evaluated the relationship between crash risk and access point spacing on two-lane and multi-lane highways across the state of Iowa.

Interchange Deceleration Lane Design Based on Naturalistic Driving Speed and Deceleration Rates

Dan Xu (1st Place Poster Award Winner) and Chennan Xue

(Poster updated 8/1/2018)

The Green Book provides the minimum lengths of deceleration lanes. The length recommendations provided by the 2011 edition are similar to the documents published in 1965, which were based on the data collected in the 1930s and had not been updated. (Fitzpatrick et al., 2012; Abdelnaby, 2014) Data was obtained from NDS dataset, including Video and Time Series Report.

A Probabilistic Model to Predict Intermittent Sight Distance Obstruction at Unsignalized Intersections on High-Speed Rural Divided Highways

Chennan Xue and Dan Xu

Minor-road left-turn vehicles’ views are likely to be blocked by major-road right-turn vehicles on the conventional right-turn lane at unsignalized intersections.

Conclusions

Congratulations to our 2018 Student Poster Winners!

First Place went to Dan Xu (Auburn University)

2nd Place Tie to Rob Sanders (Brigham Young University)

2nd Place Tie to Md Atiquzzman (Auburn University)

Student Poster Participants:

Effects on Business Activity

Operational Effects of Geometrics and Access Management, 2015

TRB’s Transportation Research Record: Journal of the Transportation Research Board, No. 2486, explores 10 papers related to operational effects of geometrics and access management in the transportation sector, including:

Freeway access management activities have traditionally taken a nominal approach to safety. Acceptable safety performance is presumed to result from attaining some desired interchange or ramp spacing. This approach oversimplifies driver behavior and complex interactions between roadway geometrics, traffic operations, and safety. The objective of this paper is to quantify the relationship between ramp spacing and freeway safety, with safety defined as number of accidents, or accident consequences, by kind and severity, expected to occur during a specified time period.

      This report represents Kentucky’s continued efforts to institute a state-wide access management policy, as set forth in the 2004-2008 Kentucky Transportation Cabinet (KYTC) Joint Strategic Plan.  The suggestions made herein build upon the initial recommendations laid out in Access Management for Kentucky (which had also included an access management implementation plan).

Williams, K. and H. Levinson. “Access Management Past, Present and Future,” Proceedings of the 8th National Access Management Conference, Baltimore, MD, (2008)

This historical overview of the evolution of access management practice would be useful for Chapter 1 of the AMM2. Another key reference that could supplement any such discussion of the history of AM is: P. Demosthenes, “Access Management: An Historical Perspective” presented to the International Right of Way Association, Albuquerque, NM (1999).

Dixon, K. and R. Layton, “The Influence of Human Factors on Access Management Design,” 4th International Symposium on Highway Geometric Design (2010)