1. Posting Bridges for Specialized Single-Unit Trucks
Specialized Hauling Vehicles are closely spaced multi axle single unit trucks introduced in the last decade. Examples include dump trucks, construction vehicles, solid waste trucks, and other hauling trucks. They are considered legal in all states, if state laws do not explicitly exclude such vehicles.
Bert Hartman
May 2016

6. FHWA Memo on SHV Ratings November 2013
Category 1 Bridges
Rating factors less than 1.3 for any of the 3 standard legal vehicles
Must be complete by December 2017
Category 2 Bridges
All remaining load ratings need to be updated for the SHV’s
Must be complete by December 2022
3710 Bridges Total, 2800 Local Agency

7. Map of bridges to be evaluated by December 2017 is available

8. Weight Limit Reduced for Legal Loads

9. Weight Limit Reduced for Single Unit Vehicles Only

10. Coordination with FHWA on 29 Posted Bridges – 15 Tons or Less

11. Bridge With 15 Foot Spans

12. Concrete Bridges With No Plans (246)
Load capacity cannot be calculated
Judgement is used
Bridges in service more than 20 years with no distress have adequate load capacity for legal loads up to the SU4
Concrete bridges without plans that are in fair or better condition will be posted for the SU5, SU6, and SU7

13. Concrete Bridges With No Plans
Reduced capacity based on condition

14. 728 Category 1 Bridges To Rate
259 Reinforced Concrete Girder
213 Timber
178 Steel I Girder
43 Steel Truss
15 Arch Bridges
12 Complex Bridges
4 Culverts
2 Post Tensioned Girder
2 Steel Box Girder

15. 186 Category 1 Bridges Rated
59 Reinforced Concrete Girder
20 Rating Factors Above 1.0
39 Under Review
126 Steel I Girder
15 Rating Factors Above 1.0
111 Under Review (Bracing Issues)
1 Post Tensioned Girder
1 Rating Factor above 1.0

16. Category 1 Load Rating Status
Arch Bridges
Procedures under development
2 bridges to be rated
13 remaining arch bridges
Timber
4 bridges to be rated
194 remaining timber bridges

17. Load Restriction Letters
There are currently 40 bridges that are in progress for writing load restriction letters on.

18. Steel I-Girder Bridge Under Review
Douglas County Bridge 19C209

19. Steel I-Girder Bridge Under Review

20. Retrofit of ODOT Bridge

21. Retrofit of ODOT Bridge
96 holes drilled in the deck of a 22 foot by 26 foot bridge
Cost $32,000

22. Steel I-Girder Bridge, Steel Deck

23. Lake Slough – 99W Built in 1919

24. Poor Reinforcement Details
A load restriction letter was sent to post this bridge at 12/20/24 for the three classic legal trucks.

25. Load Testing

26. Lake Slough Advanced Analysis to avoid load Posting
Monthly monitoring until replaced
Replacement to be bid in Sept 2016
Project Estimate- $2.9M

27. Ochoco Creek Widened Both Sides – 1954

28. No Plans for the original Bridge Freeze/Thaw Damage Shear and Flexure Cracks
Recommended Posting at 13/20/20 based on criteria for bridges with no plans. Letter sent in April.
Bridge Designer and Materials Engineer investigated original structure to find additional rows of rebar using a rebar locator. Concrete was chipped away to identify reinforcement. The resulting load rating was less than the original analysis that was for without plans. Based on history of service carrying unrestricted loads, redundant load paths by having seven girders.
Recommended Posting at 13 Tons in May.
District wanted to use barriers and put traffic on widened structure, but widening was too narrow for that.
Proof Load Test in early May.
Discussion of using a temporary Acrow Bridge
Letter to the OTC in May to add the bridge to the STIP for replacement

29. Temporary Repair

30. Repair Cost - $55K Replacement Cost -$2.9M

31. Fixing America’s Surface Transportation Act (FAST Act)

32. Fixing America’s Surface Transportation Act (FAST Act)
Interstate and within reasonable access to the Interstate.
Emergency Vehicle Limits
86,000 Lbs. GVW
24,000 Lbs. Single Steer Axle
62,000 Lbs. Tandem Axle

34. FHWA Memo on FAST Act
States Must Consider These Vehicle Weight Limits When Load Rating And Posting Highway Bridges To Maintain Compliance

35. Emergency Vehicle Tire Width
OAR (6/18/2015)
635 Pounds/Inch of Tire Width
1950’s and 1960’s bridges with “thin decks”
Pavement fatigue damage increases to the fourth power

36. THE END