MEDIAN GUIDE RAIL ASHE PRESENTATION 1/09/2013

1. MEDIAN GUIDE RAIL ASHE PRESENTATION1/09/2013

2. Median Guide Rail Presentation Presented by: David Bizuga, Manager Roadway Design Group 1 Robert Malinoski, Project Engineer (Retired) NJDOT

3. Median Barriers • Show Film: Median Barriers, A Solution to Cross-Median Crashes, 18 minutes

4. Beam Guide Rail, Dual Faced

5. Dual Faced Beam Guide Rail First Hit

6. Dual Faced Beam Guide Rail First Hit

7. Dual Faced Beam Guide Rail Second Hit

8. Dual Faced Beam Guide Rail First and Second Hits

9. Modified Thrie Beam Guide Rail, Dual Faced

10. Three Strand Cable Guide Rail, Low Tension: In-line Anchor (2000’ max. spacing),End Anchor and Penetrating Hit

11. Three Strand Cable Guide Rail Post, 3-Strand Heights At 21”, 26” and 30” Above Ground

12. More Cable

13. Old Figure 8-Q

14. Current Figure 8-T

15. Median Barrier Warrants • Interstates, Freeways • Fig. 8T: High Speed access-controled highways with traversable slopes 10;1 or flatter. • If optional as per Fig. 8T, evaluate cross median accident history. The accident history warrant should meet one of the following conditions: • 0.5 cross median crashes/mile/year of any crash history • 0.12 fatal cross median crashes per mile per year • Both a. & b. above require a min. of 3 accidents within a 5 year period.

16. Land Service Highways You Need to evaluate the following: • Number of crossovers • Prevailing reason: Accident history as per a. & b. in previous slide • Alignment • Sight distance • Design speed • Traffic volume • Median width: Use Figure 8-A for clear zone for median cross over protection.

17. Figure 8A Clear Zone (Lc)The following table contains the suggested range of clear zone distances on tangent sections of roadway based on selected traffic volumes, speed and roadside slopes.

18. Median Width Up to 12’ 13’ to 26 Above 26’ Median Barrier Type Concrete Barrier Curb Concrete Barrier Curb (Preferred Treatment) or BGR, Dual Faced or Modified Thrie Beam, Dual Faced BGR, Dual Faced or Modified Thrie Beam, Dual Faced Median Barrier Types

19. Modified Thrie Beam, Dual faced in Lieu of BGR, Dual Faced • Horizontal radius < 3000’ or • A split profile with 6:1 side slopes or steeper • Placed flush with edge of shoulder 5’ or less in width • 12% or more trucks • Traffic Volume>15,000 vehicles/lane (IE: 4 lane section > 60,000 AADT)

20. Concrete Barrier Curb • Where barrier curb is used to shield an obstruction (bridge piers, abutments, sign bridges, etc.), a minimum offset of 3.25’ from the gutter line to the face of the obstruction shall be used, since high profile vehicles have a tendency to lean when impacting barrier curb at a high speed (60 mph or greater) and angle (25 degrees) & may strike the obstruction behind it.

21. F-Shape Concrete Barrier

22. Single Slope Concrete Barrier

23. Approach end beyond clear zone Dual Faced BGR or Modified Thrie Beam Concrete Barrier Curb End Treatment End Anchorage Tapered Concrete Terminal Section, CD-607-3.5 Median Barrier End Treatments

24. Foundation Tube End Anchor(New Beam Guide Rail Anchorage)

25. Tapered Concrete Terminal Section

26. Approach end within clear zone Dual Faced BGR or Modified Thrie Beam Concrete Barrier Curb End Treatment TGRET Crash Cushion such as a Quad Guard Median Barrier End Treatments Note: Where Posted Speed is less than or equal to 40 MPH, a Tapered Concrete Terminal Section may be used on Concrete Barrier Curb, CD-607-3.5.

27. Telescoping Guide Rail End Terminals:Crash Cushion Attenuating Terminal (CAT)

28. Crash Cushion

30. High Angle Hits Can Cause Failure

31. Substandard Guide Rail

32. Substandard Guide Rail

33. Substandard Guide Rail

34. Substandard Guide Rail

35. Substandard Guide Rail

36. Substandard Guide Rail

37. Incorrect Treatment/Substandard Guide Rail

38. Incorrect Treatment/Substandard Guide Rail

39. Incorrect Placement, Check Your Truck Turns

40. It Seemed Like a Good Idea at the Time

41. It Seemed Like a Good Idea at the TimePart 2