Title

EVALUATION OF TWO NEW CROSSBUCK DESIGNS FOR PASSIVE HIGHWAY-RAILROAD GRADE CROSSINGS

Document Type

Journal Article

Publication Date

1999

Subject Area

operations - traffic, operations - frequency, planning - standards, economics - appraisal/evaluation, mode - rail

Keywords

Visual perception, Visual obstructions, Traffic signs, signals and markings, Traffic signs and signals, Traffic control devices, Standards, Snow, Risk taking, Reflectors, Reflectorized materials, Reaction time, Railroad grade crossings, Photometry, Photometrics, Ohio, Night, Manual on Uniform Traffic Control Devices, Level crossings, Highway signs, signals and markings, Highway railroad grade crossings, Highway rail intersections, Grade crossings, Fog, Design, Crossbucks, Accident rates, Accident frequency, Acceptance

Abstract

Two new crossbuck designs for use at passive highway-railroad grade crossings were evaluated. The standard improved and the buckeye crossbuck were evaluated in Ohio with respect to their potential to alter driver risk-taking behavior (Part I), their accident reduction potential (Part II), user acceptance (Part III), and with respect to their photometric performance at night (Part IV). It was found that the percentage of noncompliant drivers was about the same for both crossbuck designs, with slightly more conservative risk-acceptance times obtained for the Buckeye crossbuck. Based on the past 10 years of Ohio railroad crossing (RRX) accident history, the overall number of accidents at passive RRX has continued to drop. Since the statewide installation of the two new crossbuck designs, no accident reduction pattern could be attributed to one of the two crossbuck designs. A user acceptance survey indicated an overwhelming preference for the Buckeye crossbuck among the user groups surveyed. Photometric crossbuck luminance measurements conducted under automobile low-beam illumination at night indicate that thanks to their increased reflectorization, both new designs provide superior visual stimuli to an approaching driver at night. The Buckeye crossbuck provides by far the strongest visual signal among the measured crossbucks at night. Amendments to the national standard for crossbucks at passive RRX in the "Manual on Uniform Traffic Control Devices" are recommended. Postreflectorization (four-sided) is recommended and the additional use of a striped, angled shield is recommended in situations that require a maximum visual stimulus, ensuring the shortest possible perception reaction times, and in situations that involve visual obstructions, frequent fog, or blinding snow.