1. HSM Practitioner’s Guider for Two-Lane Rural Highways Workshop
HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
August 2010
Exercise IV – US 52 from Sageville to Holy Cross – Group Exercise
- Session #8
Session #8 – Exercise IV – US 52 in Iowa (west of DuBuque and the Mississippi River) – Group exercise for all issues
Session 8 – Exercise IV – Group Exercise

2. Exercise IV: US 52 from Sageville to Holy Cross
HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
August 2010
Exercise IV: US 52 from Sageville to Holy Cross
Learning Outcomes:
Compute combined predicted safety performance of x-section, grade, curvature, and intersections
Compare predicted safety performance to actual safety performance
Identify greatest safety shortfall
Identify priorities for improvement
Learning Objectives for Session #8 – Exercise IV – Overall Group Exercise
Session 8 – Exercise IV – Group Exercise

3. HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
August 2010
Session 8 – Exercise IV – Group Exercise

4. HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
August 2010
Session 8 – Exercise IV – Group Exercise

5. HSM Practicitioner's Guide for Two-Lane Rural Highways Workshop
Exercise IV: US 52 from Sageville to Holy Cross – Segments/Grade/Curves
August 2010
LOCATION
NUMBER
On Roadway Segments 63
Within Intersection 16
Intersection Related 1
On-Grades 3
On Curves 39
Total
122
Crashes by location
Session 2 – Exercise I

6. HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
Exercise I – US 52 from Sageville to Holy Cross
August 2010
Geometric Information:
Length: miles
AADT: 2,500
Lane Width: 11 feet
Shoulders:
Paved 0 feet
Gravel 4 feet
Hazard Rating: 5
Driveways: on level tangent segments
Total Length of Curves = 4,826 ft or mi
Total Length of Grades = 13,400 ft or 2.54 mi
US 52 Geometric Plan information
Session 8 – Exercise IV – Group Exercise

7. HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
August 2010
Exercise I – US 52 from Sageville to Holy Cross
Grade Section #
% Grade
Length in ft 1
5.6%
200 2
3.95
450 3
3.875
300 4 6
3200 5
5.2 7
700 8
5.4
350 9
3.05
400 10
900 11
5.9
1950 12
1700 13
1050 14
3.9
1150 15
4.8
150
Geometric Information Grades:
Total Length = 13,400 feet or 2.54 miles
US 52 Geometric Plan information
3%< All Grades <6%
Session 8 – Exercise IV – Group Exercise

8. HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
Exercise II: US 52 from Sageville to Holy Cross
August 2010
Geometric Information Curves:
Curve #
Delta
Degree
Radius
Length 1
104 deg
8 deg 50’ ft
1,225.5 ft
2- “A”
104 deg 33’
9 deg
836.6 ft
1162 ft
3- “B”
63 deg 56’
12 deg
477.5 ft
532.8 ft
4- “C”
67 deg 04’
558.9 ft
5- “D”
42 deg 15’
352 ft
6- “E”
62 deg 58’
524.8 ft
7- “F”
28 deg 10’
6 deg
955 ft
469.4 ft
US 52 Geometric Plan information
Total Length = 4,826 feet
Session 8 – Exercise IV – Group Exercise

9. Exercise III – US 52 from Sageville to Holy Cross
HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
Exercise III – US 52 from Sageville to Holy Cross
August 2010
Intersections on US 52: (AADTmaj = 2500)
Station
Location
Type
Side Road ADT
Predicted Crashes
Skew
Crashes x CMF
107
East of D T
450
15 deg
126
West of D
250
5 deg
262
East of F
70 deg
559 F +
300
0 deg
TOTAL ?
Session 8 – Exercise IV – Group Exercise

10. Exercise IV: US 52 from Sageville to Holy Cross
HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
August 2010
Compute the combined predicted safety performance (x-section + curves + intersections) and compare to actual safety record
Identify priorities areas for improvements
Discussion
Pause at this slide; continue on when participants have worked on the exercise.
Use Worksheet Exercise IV
Session 8 – Exercise IV – Group Exercise

11. Exercise IV – US 52 from Sageville to Holy Cross
HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
Exercise IV – US 52 from Sageville to Holy Cross
August 2010
From the US 52 corridor crash information, perform the following tasks:
Compute the combined predicted crash frequency performance (x-section + curves + intersections) and compare to actual crash record
- Where is the greatest safety shortfall?
a. Lane and Shoulder Width
b. Driveway Density
c. Roadside Design
d. Curves
e. Intersections
Session 8 – Exercise IV – Group Exercise

12. Exercise IV – US 52 from Sageville to Holy Cross
HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
Exercise IV – US 52 from Sageville to Holy Cross
August 2010
From the US 52 corridor crash information, perform the following tasks:
Identify priorities as to improvements
- where is the greatest shortfall (at 2,500 AADT)?
a. Lane and Shoulder Width (yes/no) (___%)
b. Driveway Density (yes/no) (___%)
c. Roadside Design (yes/no) (____%)
d. Curves (yes/no) (___%)
e. Intersections (yes/no) (___%)
Session 8 – Exercise IV – Group Exercise

13. HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
Exercise IV – US 52 from Sageville to Holy Cross
August 2010
Learning Outcomes:
Computed combined predicted safety performance of x-section, grade, curvature, and intersections
Compared predicted safety performance to actual safety performance
Identified greatest safety shortfall
Identified priorities for improvement
Learning Objectives for Session #8 – Exercise IV – Overall Group Exercise
Session 8 – Exercise IV – Group Exercise

14. Safety Effects Calculations Rural Two-Lane Roads
HSM Practitioner's Guide for Two-Lane Rural Highways Workshop
August 2010
Safety Effects Calculations Rural Two-Lane Roads
Too Time Consuming for Calculations and Organizing Results?
CONCERNS:
Excel spreadsheet facilitates calculations and delivers results in an organized format!
GOOD NEWS:
Cover slide showing title, event title, location and date: ‘Overview of the New HSM’
Session 8 – Exercise IV – Group Exercise 14

15. Questions and Discussion
HSM Practitioner’s Guider for Two-Lane Rural Highways Workshop
Safety and Operational Effects of Geometric Design Features for Two-Lane Rural Highways Workshop
May 2009
Questions and Discussion
Session 7 – Exercise III - Intersections