1. ROADWAY DESIGN CRITERIA
Tracy Borchardt February 2013 1

2. Roadway Design Criteria
The Roadway Design Criteria dated October 2012 replaces the version issued August 2002.
This was a MAJOR REVISION.
This manual will get on the same cycle as the other manuals. It will be issued in March with minor revisions. 2

3. Roadway Design Criteria
Sight Distance
Stopping
Decision
Compound Curve Lengths
SE Rates
Mainline
Ramps
K values – Vertical Curves
Crest
Sag
Added references to AASHTO Green Book
Article Stopping Sight Distance
Article Decision Sight Distance
Article Min. Length of Curves – Compound Curves
Article Superelevation Rates
Article Design Controls for Crest Vertical Curves
Article Design Controls for Sag Vertical Curves 3

4. Roadway Design Criteria
Added Definitions:
Added definitions for Service and System Interchanges
System Interchange
Service Interchange 4

5. Maximum Superelevation
For example:
Separated System Interchange criteria from Service Interchange. 5

6. Superelevation Distribution
Mainline 85% of SE runoff on Tangent
Ramps (all speeds) 80% of SE runoff on Tangent
New article.
Article 2.4.7
85% of SE runoff on tangent for mainline is NOT new.
80% of SE runoff on tangent for ramps is new. 6

7. Revised Mainline Typical Section
Revised pavement width for new typical section
Article 2.6.1
M19 Mainline
3 lanes – 39’
4 lanes – 51’
5 lanes – 63’
M20 Ramps, M21 Directional Ramps, 7

8. Typical Section – Pavement Width
Revised based on new typical section.
Lane ’ to 14’ 8

9. Typical Section – Pavement Cross Slope
Revised based on new typical section.
Crown moved from LL between L1 and L2 to inside EOP.
Lanes 3 and 4 increased to 2%
Lane 5 (or any aux. lanes) increases to 2.5% 9

10. Typical Section – Maximum Rollover
Revised based on new typical section.
Article 2.4.8
Add maximum rollover between pavement and Preferential lane of 3.5%
All other rollover criteria stayed the same. 10

11. Typical Section – Paved Shoulder Width
Revised based on new typical section.
Article 2.6.4
When used as preferential lane inside shoulder width increased by 2.5’ 11

12. Typical Section – Paved Shoulder Cross Slope
Revised based on new typical section.
Article 2.6.4
Cross slope of inside shoulder decreased from 4% to 2%
Outside shoulder decreased from 4% to 3% 12

13. Minimum Grades Mainline and Ramps:  0.5% minimum 13 Article 2.5.2
Minimum grade revised from 0.3% to 0.5%
Article 2.5.2 13

14. Use of Gutters and Curbs
Gutter Type G-2
Gutter Type G-3
New Article. Article 2.6.6
Reference Tollway Standard B1.
No portion of the gutter shall be considered part of the rideable area of the shoulder or counted as part of the shoulder width.
Gutter Type G-3 and G-2 are not allowed along unshielded embankment slopes steeper than 1:6 (V:H).
When gutter is required adjacent to a Traffic Barrier Terminal Type T1 (Special), Gutter Type G-3 Modified shall be used. Another use for Gutter Type G-3 Modified is between the paved shoulder and snow storage areas (see typical sections with retaining walls and noise walls, Reference Section M-Base Sheet Drawings).
When gutter is required adjacent to a Traffic Barrier Terminal Type T1-A (Special), Gutter Type G-2 Modified shall be used. Another use for Gutter Type G-2 Modified is between the ramp paved shoulder and snow storage areas (see typical sections with retaining walls and noise walls, Reference Section M-Base Sheet Drawings) and adjacent to an F-shape retaining wall parapet.
Type C curb is 9” high and shall only be used along toll plaza parking areas, at maintenance facilities, or in conjunction with guardrail on the tapering approach to a toll plaza. Type C curb shall not be used along the mainline.
Type C Curb 14

15. Use of Gutters and Curbs – G-3 Gutter
Table is from page 12 in RDC 15

16. Use of Gutters and Curbs – G-2 Gutter
Table is from page 13 in RDC 16

17. Use of Gutters and Curbs – G-3 Modified Gutter
Another use for Gutter Type G-3 Modified is between the paved shoulder and snow storage areas (see typical sections with retaining walls and noise walls, Reference Section M-Base Sheet Drawings). 17

18. Use of Gutters and Curbs – G-3 Modified Gutter
Another use for Gutter Type G-3 Modified is adjacent to Traffic Barrier Terminal Type T1 18

19. Snow Storage – Single Slope Parapet
New Article
Single slope barrier shown --- not clear why snow storage was necessary here 19

20. Snow Storage – Single Slope Parapet
Here is an example with many things wrong.
Single slope wall not necessary with moment slab.
Guardrail in front of a crash-worthy parapet.
Guardrail posts in concrete. 20

21. Snow Storage – F-Shape Parapet
Here is an example of an F-shape parapet with a moment slab. Again, it is not clear why snow storage is provided here.
F-shape parapet should be used when a moment slab is needed. 21

22. Snow Storage – Transitions
Transitions in and out of the snow storage areas have been a problem. Triangular area needs to be paved and gutter type needs to be “modified”. 22

23. Sideslopes 23 Revised Article. Article 2.6.7
Typical section shows the information better than the table of values does.
In general the barn roof cross section works best 23

24. Emergency Turnarounds
Clearance Opening
25’-30’
New Article. Article
Emergency turnarounds shall be located at a site that allows a minimum of 1000‘ clear stopping sight distance in both directions. The location selected shall be acceptable to the Tollway’s Maintenance staff and the Illinois State Police, District 15.
A clearance opening between 25’-30’ shall be provided between the impact attenuators placed at each end of the opening in the median barrier wall to allow for emergency vehicles to maneuver.
These are not called cross-overs 24

25. Shoulder Widths (New Structures)
Revised Article. Article 2.7.1
Mainline: Left side shoulder increased from 10’ to 12’
Ramp: Two lane pavement shoulder increase from 10’ to 12’ 25

26. Vertical Clearances 26 Article 2.7.3 Deleted values
added reference to Tollway Structure Design Manual 26

27. Toll Plazas All Electronic Tolling (AET) Mainline AET Ramp AET 27
Article 2.8
Revised Article to include All Electronic Tolling
Mainline - Open Road Tolling (ORT)/All Electronic Tolling (AET) Zones
Ramp - Open Road Tolling/All Electronic Tolling Zones
Ramp AET 27

28. Permanent Right of Way 28 Article 2.14.2
Revised values for condition when foreslope is steeper than 1:3 and fill ht. is greater than 9’
Reference Base Sheet M23 28

29. Questions ? 29