Incorporating Traffic Control and Safety Hardware Performance Functions into Risk-based Highway Safety Analysis
Traffic control and safety hardware such as traffic signs, lighting, signals, pavement markings, guardrails, barriers, and crash cushions form an important and inseparable part of highway infrastructure affecting safety performance. Significant progress has been made in recent decades to develop safety performance functions and crash modification factors for site-specific crash predictions. However, the existing models and methods lack rigorous treatments of safety impacts of time-deteriorating conditions of traffic control and safety hardware. This study introduces a refined method for computing the Safety Index (SI) as a means of crash predictions for a highway segment that incorporates traffic control and safety hardware performance functions into the analysis. The proposed method is applied in a computation experiment using five-year data on nearly two hundred rural and urban highway segments. The root-mean square error (RMSE), Chi-square, Spearman’s rank correlation, and Mann-Whitney U tests are employed for validation.
Migletz J, Fish JK, Graham JL. Roadway Delineation Practices Handbook. Report FHWA-SA-93-001. Washington, D.C.: Federal Highway Administration; 1994.
Ogden K. Safer Roads: A Guide to Road Safety Engineering. Cambridge: Avebury Technical; 1996.
IMIT. Guidelines for the Design of Road Infrastructures: D.M. n. 6792, 5/11/2001. Rome: Italian Ministry of Infrastructures and Transports; 2001.
Elvik R, Truls V. The Handbook of Road Safety Measures. Oxford: Elsevire Science; 2004.
Lamm R, Beck A, Ruscher T, Mailaender T, Cafiso S, La Cava G, Mathews W. How to Make Two Lane Rural Roads Safer. Scientific Background and Guide for Practical Application. Southampton: WIT Press;
Madanu S, Li Z, Abbas M. Life-Cycle Cost Analysis of Highway Intersection Safety Hardware Improvements. ASCE J Transportation Engineering. 2010 Feb;136(2):129-140.
De Leur P, Sayed T. Development of a Road Safety Risk Index. TRB J Transportation Research Record. 2002 Jan;1784:33-42.
Montella A. Safety Reviews of Existing Roads: Quantitative Safety Assessment Methodology. TRB J Transportation Research Record. 2005 Jan;1922:62-72.
Cafiso S, La Cava G, Montella A, Pappalardo G. A Procedure to Improve Safety Inspections Effectiveness and Reliability on Rural Two Lane Highways. Baltic J Road and Bridge Engineering. 2006 Mar;I(3):143-150.
Black KL, McGee HW, Hussain SF, Rennilson JJ. Service Life of Retroreflective Traffic Signs. FWA-RD-90-101. Washington, D.C.: Federal Highway Administration; 1991.
Wolshon B. Louisiana Traffic Sign Inventory and Management System, Final Report. Baton Rouge: Louisiana State University; 2003.
Long S, Qin R, Gosavi A, Wu CH, Ryan T, Noll C. Life Expectancy Evaluation and Replacement Schedule Development for LED Traffic Indicators. Report No. OR11.015. Jefferson City: Missouri Department of
Lindly JK, Yellapu K, Supriyasilp T. Evaluation of Retroreflectometers for the Alabama Department of Transportation. Report 02402. Tuscaloosa: University of Alabama; 2002.
Bahar G, Masliah M, Erwin T, Tan E, Hauer E. Pavement Marking Materials and Markers: Real-World Relationship between Retroreflectivity and Safety over Time. Final Report for NCHRP Project 17-28. Washington, D.C.: National Cooperative Highway Research Program, National Research Council; 2006.
Avelar, R, Carlson, P. Link between Pavement Marking Retroreflectivity and Night Crashes on Michigan Two-Lane Highways. TRB J Transportation Research Record. 2014 Dec;2404:59-67.
Guo, Y, Liu, P, Liang, Q, Wang, W. Effects of Parallelogram-Shaped Pavement Markings on Vehicle Speed and Safety of Pedestrian Crosswalks on Urban Roads in China. Elsevier J Accident Analysis & Prevention. 2015 Oct;95(B):438-447.
Klir GJ. Uncertainty and Information: Foundations of Generalized Information Theory. Hoboken: Wiley Interscience; 2006.
Hauer E. Observational Before-After Studies in Road Safety: Estimating the Effect of Highway and Traffic Engineering Measures on Road Safety. Oxford: Pergamon Press; 1997.
Ross, Jr, HE, Sicking DL, Zimmer RA, Michie JD. Recommended Procedures for the Safety Performance Evaluation of Highway Features. NCHRP Report 350. Washington, D.C.: National Cooperative Highway Research Program, National Research Council; 2005.
McCullagh P, Nelder JA. Generalized Linear Models. New York: Chapman and Hall; 1989.
Kutner M, Nachtsheim C, Neter J, Li W. Applied Linear Statistical Models. 5th Ed. New York: McGraw-Hill/Irwin; 2004.
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