1. HSM Applications to Multilane Urban Suburban Multilane Intersections
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Exercise III – Prediction of Crash Frequency Performance for Multilane Intersections and Comparison to
Substantive Crash
Performance
- Session #09
Instructor: Session #09 – Exercise III –– Prediction of Crash Frequency and application of CMFs for Urban Suburban Multilane Intersections and Comparison to Substantive Safety Performance
Session 7 –Exercise III

2. Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Learning Outcomes:
Apply Multilane Intersection Crash Prediction models
Compare predicted Crash Frequency performance to Substantive safety performance
Instructor: review the Learning Objectives for Session #11 Exercise III Applying multilane intersection Crash Frequency prediction SPF’s and CMF’s.
Session 7 –Exercise III

3. Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Intersection Information:
MINOR ROADS: Three Signalized intersections with single left turn lanes (no right turn lanes):
Bloomingdale Road 16,100 AADT
Shopping Center (north and south) 2,400 AADT
Main Street-Glen Ellyn 16,700 AADT
MAJOR ROAD: IL 64 North Avenue is 37,000 AADT
Instructor: IL 64 North Avenue major intersection traffic information
Session 7 –Exercise III

4. Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Unsignalized T- Intersections w/o left turn lanes:
Mildred AADT
Virginia AADT
Bernice AADT
Western AADT
Pearl ,500 AADT
Diane AADT
Evergreen AADT
Amy AADT
Newton AADT
Signalized 4-Approach Intersections with left turn lanes:
Bloomingdale Road 16,100 AADT
Shopping Center (north and south) 2,400 AADT
Main Street-Glen Ellyn 16,700 AADT
Instructor: North Avenue IL 64 intersection information for the mile segment from Bloomingdale Road on the west to Glen Ellyn Road on the east
Session 7 –Exercise III

5. Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Crash data for 1986, 1987, 1988 – 3 years
Intersections: Total Injury Day Night
Mildred
Virginia
Bernice
Western
Pearl
Diane
Evergreen
Amy
Newton
Bloomingdale Rd
Shopping Center
Main St-Glen Ellyn
Totals:
Instructor: “Before” crash data from IDOT Safety Section from the Phase I study for North Avenue IL 64 project
Total Crashes for the 12 intersections = 450 crashes
Injury Crashes for the 12 intersections = 154 crashes
Session 7 –Exercise III

6. Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
April 2009
Study Section:
Crash data for 1986, 1987, 1988 – 3 years
Total Injury
Crashes Crashes Day Night
Rdwy Segment
12 Intersections
Totals:
Instructor: “Before” crash data from IDOT Safety Section from the Phase I study for North Avenue IL 64 project
Session 7 –Exercise III

7. Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
April 2009
Predict the Crash Frequency Performance for the intersections using the Rural Multilane intersection models for the following:
Bloomingdale Road (signalized)
Shopping Center (signalized)
Main Street-Glen Ellyn (signalized)
Eight “T” non-signalized intersections (700 ADT)
One “T” non-signalized intersection (1,500 ADT)
Instructor: Task 1 with the five sub tasks for the three major intersections, the eight minor intersections of 700 adt and one intersection of 1,500 adt for the “before” condition as a “rural” multilane highway
Use Worksheet Exercise III
Session 7 –Exercise III

8. Nspf int = exp(a + b ln(AADTmaj) + c ln(AADTmin))
Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Predict the Crash Frequency Performance for the intersections using the Rural Multilane intersection models for the following:
Bloomingdale Road (signalized)
Nspf int = exp(a + b ln(AADTmaj) + c ln(AADTmin))
= exp( ln(37,000) ln(16,100)
Instructor: presentation of task 1 subtask a prediction as a multilane RURAL intersection
= exp( )
= exp(3.676) =
39.5 crashes per year
Session 7 –Exercise III

9. Nspf int = exp(a + b ln(AADTmaj) + c ln(AADTmin))
Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Predict the Crash Frequency Performance for the intersections using the Rural Multilane intersection models for the following:
Shopping Center (signalized)
Nspf int = exp(a + b ln(AADTmaj) + c ln(AADTmin))
= exp( ln(37,000) ln(2,400)
Instructor: presentation of task 1 subtask a prediction as a multilane RURAL intersection
= exp( )
= exp(3.035) =
20.8 crashes per year
Session 7 –Exercise III

10. Nspf int = exp(a + b ln(AADTmaj) + c ln(AADTmin))
Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Predict the Crash Frequency Performance for the intersections using the Rural Multilane intersection models for the following:
Main Street-Glen Ellyn (signalized)
Nspf int = exp(a + b ln(AADTmaj) + c ln(AADTmin))
= exp( ln(37,000) ln(16,700)
Instructor: presentation of task 1 subtask a prediction as a multilane RURAL intersection
= exp( )
= exp(3.689) =
40.0 crashes per year
Session 7 –Exercise III

11. Nspf int = exp(a + b ln(AADTmaj) + c ln(AADTmin))
Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Predict the Crash Frequency for the intersections using the Rural Multilane intersection models for the following:
Eight “T” stop control of approach at 700 AADT
Nspf int = exp(a + b ln(AADTmaj) + c ln(AADTmin))
= exp( ln(37,000) ln(700)
Instructor: presentation of task 1 subtask a prediction as a multilane RURAL intersection
= exp( )
= exp(1.684) =
5.39 crashes per year
Session 7 –Exercise III

12. Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
April 2009
Predict the Crash Frequency for the intersections using the Rural Multilane intersection models for the following:
Eight “T” stop control of approach at 700 ADT
For eight locations:
N = 8 x 5.39
Instructor: presentation of task 1 subtask a prediction as a multilane RURAL intersection
= 43.1 crashes per year
Session 7 –Exercise III

13. Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Predict the Crash Frequency Performance for the intersections using the Rural Multilane intersection models for the following:
one “T” stop control of approach at 1,500 ADT
Nrural = exp(a + b LN(AADTmajor)+ c (AADTminor))
= exp( ln(37,000) ln(1,500)
Instructor: presentation of task 1 subtask a prediction as a multilane RURAL intersection
= exp( )
= exp(1.864) =
6.5 crashes per year
Session 7 –Exercise III

14. Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Total the Predicted Crash Frequency performance for all intersections
Bloomingdale Road (signalized)
Shopping Center (signalized)
Main Street-Glen Ellyn (signalized)
Eight “T” non-signalized intersections (700 AADT)
One “T” non-signalized intersection (1,500 AADT)
39.5
20.8
40.0
Instructor: presentation of task 2 summing the individual major and minor intersections
43.1
6.4
Total
Session 7 –Exercise III

15. Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Compare the Substantive Intersection Crash Frequency Performance to the Predicted Crash Frequency Performance:
Substantive Safety Performance =
450 in 3 yrs
150 per year
Predicted Crash Frequency Performance =
Instructor: task 3
The IL 64 crash data does not break out the individual intersection crash info for the non-signalized intersections; only the signalized intersections. The non-signalized intersection crash data is included in the 3-years of segment crash data, it’s difficult to determine the actual safety performance.
149.9 per year
Substantive Safety Performance less than Predicted Crash Frequency?
About Same
Session 7 –Exercise III

16. Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Comparison of the Total Predicted Crash Frequency to Actual performance for all intersections:
Predicted
Actual
Bloomingdale Road (signalized)
Shopping Center (signalized)
Main Street-Glen Ellyn (signalized)
Eight “T” non-signalized intersections (700 AADT)
One “T” non-signalized intersection (1,500 AADT)
39.5
56.7
20.8
6.0
40.0
48.7
Instructor: presentation of task 2 summing the individual major and minor intersections
43.1
31.3
6.4
7.3
Total
150.0
Session 7 –Exercise III

17. Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Learning Outcomes:
Applied Multilane Intersection Crash Frequency Prediction models
Compared predicted Crash Frequency performance to Substantive Safety performance
Instructor: review the Learning Outcomes for Session #11 Exercise III
Session 7 –Exercise III

18. Questions and Discussion
Exercise III – IL 64 North Avenue from Bloomingdale Road to Main Street-Glen Ellyn
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
April 2009
Questions and Discussion
Session 7 –Exercise III