RISK-BASED MANAGEMENT OF GUARDRAILS: SITE SELECTION AND UPGRADING

1. RISK-BASED MANAGEMENT OF GUARDRAILS: SITE SELECTION AND UPGRADING Presented to The Project Steering Committee by The Center for Risk Management of Engineering Systems September 15th, 2000

2. Project Team VDOT Richmond District Travis Bridewell, District Traffic Engineer, Richmond District Jeff Wilkinson, Transportation Engineer, Traffic Engineering Section, Richmond District Baron Gissendaner Virginia Transportation Research Council Wayne S. Ferguson, Research Manager Steering Committee Steve Edwards, Transportation Engineer Senior, Traffic Engineering Division, Central Office Paul Kelley, Transportation Engineer, Location and Design Division, Central Office Charlie Kilpatrick, Fredericksburg Resident Engineer, Fredericksburg District Bob McCarty, Senior Field Operations Engineer, Federal Highway Administration - Richmond Ginger Quinn, District Safety Officer, Traffic Engineering Section, Salem District Nancy Berry, Transportation Engineering Program Supervisor, Location and Design Division, Central Office

3. Project Team (cont.) Additional Current and Former Resident Engineers Bill Bushman Angela Tucker Willie Gentry Alan Leatherwood Dan Roosevelt Center for Risk Management of Engineering Systems James H. Lambert, Research Assistant Professor of Systems Engineering Yacov Y. Haimes, Quarles Professor of Systems Engineering and Civil Engineering and Center Director Jeffrey A. Baker, BS/MS Student Kenneth Peterson, Undergraduate Student Capstone Team Christian Baldwin Irene Jacoub Mike Raker

4. Agenda I. Motivation II. Data representation for Hazard Catalog III. Data representation for Corridor Screening IV. Data representation for Site Prioritization V. Discussion

5. I. Motivation

6. Motivation • Public and transportation-agency priorities concerning the location of roadway guardrails are in need of clarification • The concerns of Virginians for adequate guardrails relative to national norms are high • Current practice in some VDOT Districts for selecting locations for new guardrails is based upon citizen complaints, a general knowledge of roadway needs from local engineers, and accident history

7. Motivation (cont.) • E.g., there are hundreds of candidate locations on the thirteen-county secondary system of Richmond District; over 50,000 miles of roadway in Virginia • Kentucky developed a hazard-index point system (Kentucky Transportation Center Report KTC-89-39 "Warrants and Guidelines for Installation of Guardrail") • Particular locations in New Kent and Charles City County were the focus of a related preliminary study in Richmond District

8. Purpose and Scope • Objectives: • Review and evaluation of what others have done • Adoption of assessment methods and quantitative and qualitative factors • Development of a tradeoff methodology • Specification and prototype development of databases

9. Overview of Approach A data driven approach to assessing risk and evaluating safety of candidate guardrail locations by • Catalog • Screening phases • Evaluation phases • Data needs in a case study • Developing Software

10. Corridor Screening • Select corridors to examine

11. Site Prioritization • Select locations along given corridor

12. New Kent Case Study • Data Collection for Corridor Screening Tool • Accident statistics of given corridors • Routes 601-665 • Data Collection for Site Prioritization and Hazard Catalog Tool • Routes 611, 613, 640, 665

13. II. Hazard Catalog Tool

14. Purpose • Compile an inventory of hazard sites and guardrail coverage, and conditions of guardrails • Compare and contrast routes to determine which are in need of further study • Present in a graphical format information pertinent to decisions about improvements

15. Severity Guidelines

16. Hazard Catalog Screening

17. Hazard Catalog Screening (cont.) Size of bubbles represent cost/value

18. Hazard Catalog Screening (cont.) Size of bubbles represent cost

19. Hazard Catalog Screening (cont.) Size of bubbles represent cost/value

20. IV. Corridor Tool

21. Purpose • Compare corridors for frequency and severity of accidents • Highlight corridors that have greatest accidents/DVMT ratio • Compare results with current guardrail coverage

22. Corridor Screening

23. Corridor Screening (cont.)

24. IV. Site Prioritization Tool

25. Purpose • Decide which sites should be improved with the current budget constraint • Consider multiple criteria

26. Objective (cont.)

27. Objectives of Guardrail Selection

28. Example • Maximize length of hazard protected • Subject to budget constraints • (E.g. total cost < $30,000)

29. Site Prioritization Tool Analysis • Compare sites and their characteristics (cost, severity, ADT) • Select routes with the highest benefit/cost ratios that fall within a budget constraint

30. Site Prioritization

31. Site Prioritization (cont.)

32. Site Prioritization (cont.)

33. Site Prioritization (cont.) Size of bubbles represent cost/value ($)

34. Site Prioritization (cont.) Size of bubbles represent cost/value ($)

35. Site Prioritization (cont.) Size of bubbles represent cost/value ($)

36. Comparison of Results • Results can be compared to show the consistency of need at a location • Budget constraint kept constant • Example: • Locations 1,2,3,7, and 9 are recommended by the model to maximize severity protected

37. Summary and Future Work • The spreadsheet tools provides a way to optimally select hazard sites within the budget constraints • Comparing results from different solutions can reveal the locations most appropriate for improvement

38. Summary and Future Work (cont.) • Issues for Implementation • Definition of Severity • Environmental Factors • Curvature of Road

39. Web Page • http://www.virginia.edu/~risk/guardrail/ • Public reference for guardrails and treatment of issue • Communication between VDOT and Capstone • Software, instructions, and powerpoint

40. The Web Site • Statement of Work • Guardrail Photos • Current Team • Contact Information • Related Links • Downloads

41. Discussion