looking into virginia’s work - vasitejun 28, 2016 · 5-year crashes 4 annual counts 3,445 3,464...
TRANSCRIPT
David RushWork Zone Safety Program Manager
Traffic Engineering Division, Central Office
Young-Jun KweonSenior Research Scientist
Virginia Transportation Research Council
VASITE Annual
Meeting
June 30 2016
Looking into Virginia’s Work
Zone Safety 2011-2015
OUTLINE
PART I Work Zone
PART II Work Zone
2
by David
by Young-Jun
Crash Statistics
Safety Measures
PART I
Work Zone
Crash Statistics
3
5-Year Crashes
4
Annual Counts
3,445 3,464 3,404
4,071
2,622
0
1,000
2,000
3,000
4,000
2011 2012 2013 2014 2015
Yea
rly
Cra
shes
Year
Increased risk
for workers and
motorists.
Crash Severity
5
Fatal Injury
(K)
58
0%
Incapacitating
(A)
822
5%
Non-Incapacitating
(B)
2,777
16%
Possible Injury
(C)
1,998
12%
No Injury
(O)
11,351
67%
5-Year Crashes:
▪ 17,006 WZ crashes
▪ 66 WZ fatalities
6
Number of Vehicles
5-Year Crashes
1 Vehicle
2,428
14%
2 Vehicles
11,466
68%
3 Vehicles
2,452
14%4 Vehicles
523
3%
5+ Vehicles
137
1%
5-Year Crashes
Collision Type
7
Still the #1 crash in WZs!
Rear End
9,329
55%
Angle
2,415
14%
Fixed Object,
Off Road
2,218
13%
Sideswipe,
Same Direction
182
1%
Others
2,862
17%
5-Year Crashes
Light Condition
8
Daylight
11,690
69%
Darkness,
Road Lighted
2,647
16%
Darkness,
Road Not
Lighted
1,981
12%
Others
688
4%
5-Year Crashes
Unknown includes non-VDOT roads or missing information.
Functional Class
9
Rural Interstates
869
5%
Rural Routes
833
5%
Urban Interstates
8,435
50%
Urban Routes
5,036
30%
Unknown
1,833
11%
5-Year Crashes
District
10
Bristol
467
3%
Salem
759
4%
Lynchburg
289
2% Richmond
1,870
11% Hampton
Roads
2,237
13%
Fredericks-
burg
1,085
6%
Culpeper
392
2%Staunton
442
3%
Northern
Virginia
9,465
56%
Percentage in 5-Year Crashes
DistrictBy Light Condition
11
Bristol Salem Lynchburg RichmondHampton
Roads
Fredericks-
burgCulpeper Staunton
Northern
Virginia
Daylight 88% 75% 79% 67% 59% 72% 78% 77% 68%
Darkness, Road Lighted 3% 6% 9% 8% 31% 3% 4% 3% 18%
Darkness, Road Not Lighted 6% 15% 9% 21% 6% 22% 13% 16% 10%
Others 4% 4% 3% 4% 4% 3% 5% 5% 4%
0%
20%
40%
60%
80%
100%
Colu
mn
Per
cen
t
District
Passenger Car
19,326
54%
SUV
6,335
18%
Pickup Truck
3,691
10%
Truck
3,129
9%
Van
2,118
6%
Others
661
2%
Motorcycle
302
1%
Vehicles in 5-Year Crashes
Vehicle Type
12
PART II
Work Zone
Safety Measures
13
by Young-Jun
VDOT’s Metrics
VDOT had been using two metrics to measure work zone
safety performance of Virginia
14
Annual Persons Killed and Serious Injury in Work Zones
0
2
4
6
8
10
12
14
16
18
20
2004 2005 2006 2007 2008
Year
Pers
on
s K
ille
d
0
50
100
150
200
250
300
350
400
450
Pers
on
s S
eri
ou
sly
In
juri
ed
Deaths Serious Injuries
Issues with the Metrics
Count of Persons. It is affected by:
▪ Number of persons in a vehicle
▪ Number of vehicles in a crash
No exposure accounted. Examples of exposures are:
▪ Number of work zones
▪ Length of work zones
▪ Number of vehicles passing through work zones
15
Count Measures
▪ Directly measure traffic safety consequences
▪ (e.g.) Numbers of fatalities & fatal crashes in a year
Exposure Measures
▪ Capture level of an exposure to traffic crash risk
▪ (e.g.) Number of work zones in a year
Rate Measures
▪ Reflect both count and exposure measures
▪ (e.g.) Fatal crashes per 1,000 work zones in a year
3 Types of Measures
2015✓ 10 work zone crashes✓ 5 work zones✓ Each work zone 10 miles long✓ Each work zone lasted 1 month
2014✓ 10 work zone crashes✓ 10 work zones✓ Each work zone 1 mile long✓ Each work zone lasted 1 year
We need exposure measures!!
16
Research Project
Title: Work Zone Safety Performance Measures for
Virginia
Team: Young-Jun Kweon, Mike Fontaine, In-Kye Lim
Review Panel: David Rush, Mark Cole, Tim Rawls,
Forester Wright
17
4 Performance Measures
① total crashes, ② fatal & injury crashes
③ crashes per work zone-hour-mile
④ fatal & injury crashes per work zone-hour-mile
8 Summary Measures
① fatalities and injuries
② crashes per work zone, ③ crashes per work zone-hour, ④ fatal &
injury crashes per work zone,
⑤ work zones, ⑥ work zone-hours, ⑦ work zone-miles, and ⑧ work
zone-hour-miles
Virginia’s WZ Safety Measures
18
Performance MeasureAll Work Zone Crashes
19
Summary MeasureWork Zones
20
Summary MeasureWork Zone-Hours
21
Summary MeasureWork Zone-Miles
22
Summary MeasureWork Zone-Hour-Miles
23
Performance MeasureAll WZ Crashes
Per Million Work Zone-Hour-Miles
24
Cautions
Technical definition of a work zone crash
▪ Previous publications used road defect information whereas the
current one uses work zone status information.
Issues with rate measures
▪ Valid as long as “linearity condition” is met.
▪ Omitted influential factors (e.g., traffic volume and work zone type)
25
26
Question?Thank You!