1. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 126 Japan D a = expected damage in collision accidents after installation M = maintenance costs I = annual allocation for cost of barrier installation

2. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 127 Japan Barriers in Japan are required as follows [JRA, 1964]: On city roads elevated more than 2 meters On other roads elevated more than 2 meters and with a radius of curvature of less than 300 meters

3. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 128 Japan On roads alongside railways if the road is higher than the railway, or if the road is less than 1.5 meters below the railways, and the distance between them is less than 5 meters

4. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 129 Japan Barriers in Japan are required as follows [JRA, 1964]: On sections with S-shape curves with a radius of curvature less than 300 meters On roads where the down gradient is more than 4 % On medians less than 3 meters wide and subject to bad weather conditions

5. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 130 France Barriers are required on autoroutes as follows: On medians: Where the median width is 5 meters and the expected ADT 5 years after opening of the road is at least 15000 vehicles, on 4 lane divided highways

6. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 131 France On bends along the edge of the carriageway having the smaller radius, when this is less than the normal minimum radius of 650 meters for a design speed of 100 km/hr or 1200 meters for a speed of 140 km/hr

7. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 132 France Barriers are required on autoroutes as follows: At the road edge: Along the outside of bends having a radius less than the normal minimum radius for the road On embankments where their height exceeds 4 meters, this height being reduced to 1 meter in cases of sudden changes of level

8. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 133 France In advance of ditches greater in depth than 0.5 meters Barriers should always commence with a split end. On the median they should be sited as close to the center line as possible, and the road edge so that the traffic face coincides with the exterior of the hard shoulder

9. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 134 Cost - Benefit Analysis Benefit - cost ratio of alternative 2 compared to alternative 1 B 1, C 1 = Benefits and cost of alternative 1 B 2, C 2 = Benefits and cost of alternative 2 Mak (1995)

10. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 135 What if we have 1 small project and 1 large project? The results of the ratio are the same, but we get a false analysis. Mak (1995) Cost - Benefit Analysis

11. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 136 Expected Accident Cost - Simplified E(AC) = Expected accident cost V = Traffic volume, ADT P(E) = P(encroachment) P(A|E) = P(accident given an encroachment) P(I i |A) = P(injury severity i given an accident) C(I i ) = Cost associated with injury severity i n = Number of injury severity levels Mak et al. (1998)

12. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 137 2. Compute cost-effectiveness: 1. Determine effectivenes: E = Hazard(before) - Hazard(after) Cost Effectiveness

13. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 138 Review of Standards for Virginia

14. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 139 Review of Standards for Virginia NameYears GR HDW1989-1996 GR 1A1966-1978 GR 1B1966-1978 ALT 1B1975-1978 GR 1C1966-1978 GR 21989-1996 GR 2A1966-1996 GR 2B1966-1978 ALT 2B1975-1978 GR 2C1966-1978 GR 2D1978 GR 31966;1989 GR 41966-1978 GR 4A1970-1978 GR 51966-1978 GR 61970-1996 GR 71989-1996 GR 81989-1996 GR 8A1989-1996 GR 8B1989-1996 GR 8C1989-1996

15. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 140 Review of Standards for Virginia NameYears GR 91996 GR 101996 GR SP1989-1996 BN 11996 BGR 011996 GR FOA-11989-1996 GR FOA-21989-1996 GR FOA-41996 GR INS1989 MB 1A1966-1973 MB 1B1966-1973 MB 1C1966-1973 MB 31978-1996 MB 3A1966-1989 MB 3B1966-1978 ALT 3B1975-1978 MB 3C1966-1978 MB 41966-1978 MB 51966-1968 MB 5A1978-1989 MB 6A1971-1975 MB 6B1971-1975

16. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 141 Review of Standards for Virginia NameYears MB 7A1978-1989 MB 7A PC1989 MB 7B1978-1989 MB 7C1978-1989

17. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 142 Review of Standards for Virginia 196019651975197019801985199019952000 GR HDW GR 1A GR 1B ALT 1B GR 1C GR 2 GR 2A GR 2B ALT 2B GR 2C GR 2D GR 3 GR 4

18. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 143 Review of Standards for Virginia 196019651975197019801985199019952000 GR 4A GR 5 GR 6 GR 7 GR 8 GR 8A GR 8B GR 8C GR 9 GR 10 GR SP BN 1 BGR 01

19. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 144 Review of Standards for Virginia 196019651975197019801985199019952000 GR FOA-1 GR FOA-2 GR FOA-4 GR INS MB 1A MB 1B MB 1C MB 3 MB 3A MB 3B ALT 3B MB 3C MB 4

20. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 145 Review of Standards for Virginia 196019651975197019801985199019952000 MB 5 MB 5A MB 6A MB 6B MB 7A MB 7A PC MB 7B MB 7C

21. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 146 A Data Driven Approach to Risk Assessment and Safety Evaluation of Guardrail

22. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 147 Outline Objectives and activities Background –Risk and Safety –Traffic Risk Assessment –Accident Statistics Examination of HTRIS Data Collection –Corridor Analysis Future Work

23. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 148 Objectives Conduct background research into risk assessment and safety evaluation Identify necessary data for risk assessment of traffic accidents Gather accident statistics –New Kent County as case study –Establish method for retrieving information from HTRIS –Make recommendations for future methods of gathering data

24. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 149 Objectives (cont.) Examine available data –Generate method to measure risk –Evaluate safety at various locations Examine and evaluate safety countermeasures

25. Center for Risk Management of Engineering Systems University of Virginia, Charlottesville 150 Risk Measurement of probability and severity of adverse effects (Lowrance, 1976) The potential for unwanted negative consequences of an event or activity (Rowe, 1977) Chancing of negative outcome (Rescher, 1983) Expected result of the conditional probability of the event times the consequences of the event given that it has occurred (Gratt, 1987) Unintended or unexpected outcome of a decision or course of action (Wharton, 1992)