1. Traffic Barrier Guidelines Other Considerations Workshop V September-October 2015

2. Starts at the Site Visit AOC 1 Identify AOC’s 1.Bridge Pier 2.Bridge Cone 3.Light Pole 4.Control Cabinet 5.Sign Electric Panel 6.Sign Foundation 7.Sign Panel 8.Trees AOC 2 AOC 3 AOC 4 AOC 5 AOC 6 2 How to address the area overall? AOC 7 AOC 8

3. AOC’s in Close Proximity 3

4. AOC in Close Proximity Example #1 GAP < 100’ 4

5. 14+25 Culvert - AOC #1 14+03.12 17+22 OH Sign- AOC #2 15+70 16+12.5 17+08.12 Upstream Terminal End 19+05 19+17.5 Downstream Terminal End Upstream Terminal End Downstream Terminal End 95.62’ Gap Total Length of Need = 480’ EOTW AOC’s in Close Proximity 5 PON 16+00 18+95

6. AOC in Close Proximity Example #2 GAP > 100’ 6

7. 14+25 Culvert - AOC #1 14+03.12 17+72 OH Sign- AOC #2 15+70 16+12.5 17+58.12 Upstream Terminal End 19+55 19+67.5 Downstream Terminal End Upstream Terminal End Downstream Terminal End 145.62’ Gap EOTW AOC’s in Close Proximity 7 PON 16+00 19+45 Length of Need Length of Need

8. AOC in Close Proximity Example #3 Overlap 8

9. 14+25 Culvert - AOC #1 14+03.12 16+22 OH Sign- AOC #2 15+70 16+12.5 16+08.12 Upstream Terminal End 18+05 18+17.5 Downstream Terminal End Downstream Terminal End 4.38’ Overlap Upstream Terminal End Total Length of Need=380’ EOTW AOC’s in Close Proximity 9 PON 16+00 17+95

10. AOC in Close Proximity Format Examples 10

11. Example- AOC Summary Table Format LEGEND POINT OF NEED STATION DOWNSTREAM END OF GUARDRAIL STATION AOC SUMMARY TABLE AOC 115+0026+00 AOC 215+0022+50 AOC 316+2527+00 AOC 4 19+00 23+00 SUMMARY15+0027+00 TOTAL LON15+00 to 27+00 = 1,200 FT 11

12. AOC- Color Coded System 12

13. Color Coded AOC’s (Level Analysis) 13

14. Considerations for Adjusting Guardrail Lengths 14

15. Considerations for Adjusting GR lengths TBT T2-Condition 3  Would not be used when: Guardrail length < Minimum length 15

16. Considerations for Adjusting GR lengths Positioning of minimum guardrail length  Move upstream or downstream to avoid gap < 100’ (or) overlap with adjacent AOC. Obstacle in TBT T1/T1-A recovery area  Positioning of guardrail installation move upstream or downstream need to meet barrier limit calculation. 16

17. Combining Areas of Concern Case 1  When the two AOC’s are generally at the same station, but with different offsets. AOC 1AOC 2 AOC further from the roadway will result in the longer length of need. 17

18. Combining Areas of Concern Case 2  When a fixed object is located in the midst of a long slope AOC. V H 1: 2.5 (V:H) 18 The slope AOC will control the length of need.

19. Design Considerations 19

20. Barrier Installation Conflicts Retaining Wall Conflict Last six posts for Traffic Barrier Terminal Type T6 were omitted. Retaining wall design and location could have eliminated the conflicts. 20

21. Barrier Installation Conflicts Drainage Structure Conflict: Last two posts for Traffic Barrier Terminal Type T6 were omitted. 21

22. Traversable Element 22

23. Ground-Mounted Sign Supports (Article 3.4.1) 23 Foreslope 1:6 (V:H) or Flatter

24. Traversable Element 24

25. Barrier Clearance Distance 25

26. Barrier Terminal Connection 26

27. Drainage Structure Conflict 27

28. Parapet or Concrete Barrier Contributes Toward the LON. 28 AOC #1-Bridge Parapet Blunt End AOC #2-Waterway AOC #1-LON AOC #2-LON Bridge parapet contributes towards the shielding for AOC #2 Guardrail=LON-Terminal Contribution-Parapet Contribution

29. Runoff Path Area of Concern MVDS 29

30. Runoff Path 30 AOC #1 AOC #2

31. Runoff Path 31 AOC #1 AOC #2 LRLR Y

32. Runoff Path 32 AOC #1 AOC #2 LRLR

33. Speed Profile-Ramp Entrance Service Interchange 30 mph 20 mph 33 ---------------------------------------------------------------------------- 35 mph 40 mph 160’ 270’ Acceleration Lengths 610’ 50 mph Deceleration Length needed 315’ Length ~ 850’ Acceleration to 50 mph does not provide the required deceleration distance to reduce to 30 mph.

34. Speed Profile-Ramp Entrance Service Interchange 30 mph 20 mph 34 ---------------------------------------------------------------------------- 35 mph 40 mph 160’ 270’ Acceleration Lengths 40 mph Deceleration Length needed 185’ Length ~ 850’ Acceleration to 40 mph and holding for 395’ provides the required deceleration distance to reduce speed to 30 mph. 395’

35. Speed Profile-Mainline Exit Directional-50 mph minimum (applies to sharpest curve) Ramp with a design speed of 50 mph or greater on which vehicles do not stop. Service Interchange 50 mph 60 mph 35

36. Hot List-Common Mistakes 1. Lack of DSE Quality Control/Quality Assurance  Designers need to thoroughly check their work before submitting, and follow their own CQP. A common problem is when redundant information is not transferred properly between calculation sheets and plan view exhibits. Reference DSE Manual Section 7.0. 2. Identification of All Potential Obstacles  In many cases not all potential obstacles have been included in the BWA report. Additionally, in many cases there are obstacles identified on the location plans but not analyzed in the report. All obstacles are to be addressed as level 1, 2, 3 analyses or included in the Level 0 Table. Reference TBG Article 4.0. 3. Site Plan Information Missing  The site plan shall show the recovery area at Type T1 and T1-A terminals, label all nearby obstacles, gutters, Y at PON station only. Also the text size used should meet or exceed the minimum height (0.11”). Reference TBG Article 6.4. 36

37. Hot List-Common Mistakes 4. Drainage Structures Placed Within the Limits of Traffic Barrier Terminals  This issue often results in post spacing that is not in accordance with the Tollway Standards and modification to the Tollway Standards for terminals is not allowed. Reference TBG Article 10.3. 5. Including Items in Level 1 and Level 0 Tables That Are Not Appropriate Level Items  Per the TBG only items that are or can be made Traversable Elements should be included in the Level 1 table. Potential AOC’s not analyzed with a Level 1, 2, or 3 Analysis, shall be included in a Level 0 Table. Obstacles that are shielded by barrier for other AOC’s are Level 2 items, and are noted in the other AOC’s analysis. Reference TBG Article 5.5. 6. Not Addressing Barrier Clearance Distance  Designers need to consider the offset from the back of guardrail to light poles, sign foundations, walls, and other obstacles and note these distances on the site plans. Minimum barrier clearance distances are also provided on Tollway Standard C1, sheet 4 of 4. Reference TBG Article 9.2. 37

38. Hot List-Common Mistakes 7. Intermixing Traffic Barrier Terminal (TBT) Type T6 and TBT Type T6B  The T6 terminal is used with gutter and the T6B is used when no gutter is present. Reference TBG Articles 10.6.1 and 10.6.2. 8. Compact Disc (CD) submittal of RSAP files  When applicable, include a CD containing the RSAP (.rpd) file(s) used in the Level 3 analysis with the hard copy of submitted barrier warrant. Reference TBG Article 6.13. 9. Not giving guidance for revised sheets placement  When submitting revised sheets only, include a document with step-by-step guidance for inserting revised and/or new sheets, and removing sheets from the barrier warrant. Submitting just a revised Table of Contents is not sufficient. 38

39. Hot List-Common Mistakes 10. Not Investigating Feasible Alternatives  When evaluating potential obstacles, designers need to select alternatives that are feasible. For example, in many instances the designer has evaluated an alternative to leave an obstacle unshielded in the clear zone; this is not a feasible alternative as it violates Tollway Policy. A Level 3 Analysis requires the evaluation of two or more feasible alternatives for eliminating or reducing the severity of the obstacle. Reference TBG Article 6.13. 11. No Level 3 Analysis  When a Level 3 analysis is not performed for an obstacle that would usually warrant such an analysis, the reason for this should be given in the AOC’s analysis. Reference TBG Section 5.5.3. 12. Not Evaluating Obstacles From Both Mainline And Secondary Road Perspective  When the potential obstacle is along a ramp, C-D road, or auxiliary lane near the mainline or within the gore area, the potential obstacle needs to be evaluated from both mainline and ramp perspective. Utilize respective edge of traveled way (EOTW), speed, and volumes for each perspective and determine the controlling situation. Reference TBG Section 4.0. 39

40. Hot List-Common Mistakes 13. Analysis Of Closely Spaced Or Overlapping Potential Obstacles  When multiple potential obstacles are in the same area they need to be analyzed independently. A summary is to be included showing the controlling upstream and downstream obstacles and the rounded length of guardrail per the overall length of need. In cases where multiple obstacles exist in the midst of a long slope obstacle, they do not need to be analyzed independently, but notes need to be included in the BWA indicating this, and the obstacles must be labeled on the slope obstacle site plan (Refer to TBG Section 4.0 step 5). Reference TBG Section 4.0.5. 14. Speed Profiles Not Done Correctly  Speed profiles are required for ramp analyses to show the acceleration and/or deceleration per AASHTO and the resultant design speed at the potential obstacle. Design speeds of curves shall be shown. The format shown in the TBG Art. 6.14.1 should be followed. Reference TBG Article 6.12. 15. Slope Obstacles Not Analyzed Correctly  “Critical Slopes” are defined as foreslopes steeper than 1:3 (V:H), and do not always require shielding. The upstream and downstream limits of a slope obstacle are determined by RDG Figure 5-1b. Interpolate between cross sections to determine the limits. 40

41. Questions? 41