01552349

Component

This research presents a case study of Ohio State Route 682, a two-lane highway with a center two-way left turn lane, located in The Plains, Ohio. The primary objective of this investigation was to utilize crash data from periods before and after improvements were made to the roadway such that calibration factors for segments and intersections could be determined and applied to the predictive models. These calibration factors were calculated through a before period analysis for segments as well as for three-leg stop-controlled, four-leg stop-controlled, and four-leg signalized intersections. Each of the calculated calibration factors was applied in the after period analysis, along with the Highway Safety Manual default factor and the factor calculated for the state of Ohio, such that comparisons could be made between the three factors. As for the segments, the Ohio calculated factor produced the most accurate estimates, with percent differences between 4% and 48%. However, the crash frequencies at the intersections were best described by the default Highway Safety Model, for which percent differences ranged from 8% to 22%. The reliability of the generalized models over the jurisdiction-specific model indicates that while more specific calibration factors should produce more accurate estimates, such factors are not reliable when developed on the level of a single municipality.

This paper was sponsored by TRB committee ANB25 Highway Safety Performance.

01550057

15-4110

English

19p

2015

Transportation Research Board 94th Annual Meeting

Digital/other

References (6) ; Tables

Calibration; Case studies; Crash data; Geometric segments; Mathematical prediction; Multiway stop signs; Signalized intersections; Two lane highways

Highway Safety Manual

Ohio

Highways; Operations and Traffic Management; Safety and Human Factors; I82: Accidents and Transport Infrastructure

Transportation Research Board Annual Meeting 2015 Paper #15-4110

PRP, TRIS, TRB, ATRI

Dec 30 2014 1:20PM