Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

1

Japan

• Da = expected damage in collision accidents after installation

• M = maintenance costs

• I = annual allocation for cost of barrier installation

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

2

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

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

3

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

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

4

JapanBarriers 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

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

5

FranceBarriers 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

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

6

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

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

7

FranceBarriers 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

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

8

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

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

9

Cost - Benefit Analysis

)/()( 121212 CCBBBC

• Benefit - cost ratio of

alternative 2 compared to alternative 1•B1, C1 = Benefits and cost of alternative 1

•B2, C2 = Benefits and cost of alternative 2Mak (1995)

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

10

• 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

)/()( 121212 CCBBBC

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

11

Expected Accident Cost - Simplified

n

iii ICAIPEAPEPVACE

1

)(*)|(*)|(*)(*)(

E(AC) = Expected accident costV = Traffic volume, ADTP(E) = P(encroachment)P(A|E) = P(accident given an encroachment)P(Ii|A) = P(injury severity i given an accident)C(Ii) = Cost associated with injury severity in = Number of injury severity levels

Mak et al. (1998)

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

12

2. Compute cost-effectiveness:

1. Determine effectivenes:E = Hazard(before) - Hazard(after)

Cost Effectiveness

n

j

f

n

jwsyP

n

w

syPsyPlSE

H

1

]2

)12(6[

14.5

]3[4.31][

560,10

achievedreductionhazard

timprovementheoftannualized

essEffectiven

Cost cos

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

13

Review of Standards for Virginia

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

14

Review of Standards for Virginia

• Name Years• GR HDW 1989-1996• GR 1A 1966-1978• GR 1B 1966-1978• ALT 1B 1975-1978• GR 1C 1966-1978• GR 2 1989-1996• GR 2A 1966-1996• GR 2B 1966-1978• ALT 2B 1975-1978

• GR 2C 1966-1978

• GR 2D 1978• GR 3 1966;1989• GR 4 1966-1978• GR 4A 1970-1978• GR 5 1966-1978• GR 6 1970-1996• GR 7 1989-1996• GR 8 1989-1996• GR 8A 1989-1996• GR 8B 1989-1996

• GR 8C 1989-1996

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

15

Review of Standards for Virginia

• Name Years• GR 9 1996• GR 10 1996• GR SP 1989-1996• BN 1 1996• BGR 011996• GR FOA-1 1989-1996• GR FOA-2 1989-1996• GR FOA-4 1996• GR INS 1989

• MB 1A 1966-1973

• MB 1B 1966-1973

• MB 1C 1966-1973

• MB 3 1978-1996

• MB 3A 1966-1989

• MB 3B 1966-1978

• ALT 3B 1975-1978

• MB 3C 1966-1978

• MB 4 1966-1978

• MB 5 1966-1968

• MB 5A 1978-1989

• MB 6A 1971-1975

• MB 6B 1971-1975

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

16

Review of Standards for Virginia

• Name Years• MB 7A 1978-1989• MB 7A PC 1989• MB 7B 1978-1989

• MB 7C 1978-1989

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

17

Review of Standards for Virginia

1960 1965 19751970 1980 1985 1990 1995 2000

GR HDWGR 1AGR 1BALT 1BGR 1CGR 2GR 2AGR 2BALT 2BGR 2CGR 2DGR 3GR 4

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

18

Review of Standards for Virginia

1960 1965 19751970 1980 1985 1990 1995 2000

GR 4AGR 5GR 6GR 7GR 8GR 8AGR 8BGR 8CGR 9GR 10GR SPBN 1BGR 01

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

19

Review of Standards for Virginia

1960 1965 19751970 1980 1985 1990 1995 2000

GR FOA-1GR FOA-2GR FOA-4GR INSMB 1AMB 1BMB 1CMB 3MB 3AMB 3BALT 3BMB 3CMB 4

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

20

Review of Standards for Virginia

1960 1965 19751970 1980 1985 1990 1995 2000

MB 5MB 5AMB 6AMB 6BMB 7AMB 7A PCMB 7BMB 7C

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

21

A Data Driven Approach to Risk Assessment and Safety Evaluation of

Guardrail

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

22

Outline• Objectives and activities• Background

– Risk and Safety– Traffic Risk Assessment– Accident Statistics

• Examination of HTRIS• Data Collection

– Corridor Analysis

• Future Work

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

23

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

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

24

Objectives (cont.)

• Examine available data– Generate method to measure risk– Evaluate safety at various locations

• Examine and evaluate safety countermeasures

Center for Risk Management of Engineering Systems University of Virginia, Charlottesville

25

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)