1. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 1 RISK-BASED MANAGEMENT OF GUARDRAILS: SITE SELECTION AND UPGRADING Presented to Project Steering Committee by The Center for Risk Management of Engineering Systems February 23, 2000

2. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 2 Agenda Introduction Data driven approach to risk assessment Data representation for site screening Multiple objectives in the selection among candidate projects Discussion

3. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 3 Project Team 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 Capstone Team Christian Baldwin Irene Jacoub Mike Raker VDOT Richmond District Travis Bridewell, District Traffic Engineer, Richmond District Jeff Wilkinson, Transportation Engineer, Traffic Engineering Section, Richmond District Baron Gissendaner

4. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 4 Project Team (cont.) 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 Additional Current and Former Resident Engineers Bill Bushman Angela Tucker Willie Gentry Alan Leatherwood

5. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 5 Problem Statement Public and transportation-agency values concerning the location of roadway guardrails are in need of clarification The concerns of Virginians for adequate guardrails are high relative to the national norms Current practice in some VDOT Districts for selecting locations for new guardrails is based on citizen complaints, a general knowledge of roadway needs from local engineers, and accident history

6. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 6 Problem Statement (cont.) Kentucky has developed a hazard-index point system (Kentucky Transportation Center Report KTC-89-39 "Warrants and Guidelines for Installation of Guardrail") There are hundreds of candidate locations on the thirteen- county secondary system of Richmond District Particular locations in New Kent and Charles City County have been the focus of a related preliminary study in Richmond District

7. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 7 Purpose and Scope The effort will adopt quantitative and qualitative factors/endpoints and develop associated cost- benefit-risk tradeoff methodology to support the preliminary screening and subsequent evaluation of guardrail site selection and upgrading with limited available funding

8. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 8 Purpose and Scope (cont.) Four associated objectives: –Review and evaluation of what others have done –Adoption of assessment methods and quantitative and qualitative factors/endpoints –Development of a tradeoff methodology –Specification and prototype development of databases Acknowledge that guardrails sometimes increase danger to vehicles

9. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 9 A Data Driven Approach to Risk Assessment and Safety Evaluation of Guardrail

10. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 10 Motivation A data driven approach to assessing risk and evaluating safety of candidate guardrail locations by determining data uses for screening and evaluation phases, identifying data needs, and evaluating data collection methods.

11. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 11 Screening Select corridors to examine

12. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 12 Evaluation Select locations along given corridor

13. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 13 Data Needs Screening –Guardrail inventory % unprotected hazards % guardrail coverage % substandard guardrail –Accident history FO accidents per DVMT Fatalities caused by FO accidents –ADT –Complaint record

14. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 14 Data Needs (cont.) Evaluation –Cost (installation, upgrade) –Length of hazard –Severity of hazard –Shoulder width –Slope –Curvature

15. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 15 Accident Statistics Disadvantages –Unreported accidents –Severity iceberg –First and most harmful event –Fatalities do not occur frequently enough to be statistically predictive –Random nature of road accidents (Adams, 1996), (Michie and Bronsted, 1994)

16. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 16 Accident Statistics (cont.) Advantages –Available and assessable –Factual –Public interest (Adams, 1996), (Michie and Bronsted, 1994)

17. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 17 New Kent Case Study Initial Data Collection –Routes 609-622 Corridor Analysis –Corridors for which guardrail inventory is available –Routes 33, 106, 249, 273

18. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 18 Corridor Analysis Compare routes for frequency and severity of accidents Select routes that have greatest accidents/miles Compare results with current guardrail inventory Advantages –Reduce random chance associated with accidents –Use summary statistics available in HTRIS

19. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 19 Corridor Analysis (cont.) Disadvantages –Overlooks role of hazardous locations –Many locations of mediocre severity vs. one location of very high severity

20. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 20 Corridor Screening

21. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 21 Corridor Screening (cont.)

22. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 22 Objective Develop a graphical tool for a guardrail and hazard inventory system for resource allocation and decision making

23. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 23 Access to the New Kent Guardrail Data Graphically represent what resident engineers know using an electronic map indicating the locations of: –Guardrails –Obstacles –Accidents –Complaints, etc.

24. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 24 Electronic Map Layered spatial data, creating different views –Regional view –Zone view –Corridor view –Site view

25. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 25 Regional View