1. Load Posting For Specialized Hauling Vehicles (SHVs)

2. Overview Traditional Load Posting SHV Description SHV Posting Signs
4 axle SHV Vs. 105,500 lb. CTP
The Load Rating Equation
Load Rating Factors
Conclusion on 105,500 lb. CTP

3. Typical Legal Trucks
Type axle straight truck
50,000 lbs.

4. Typical Legal Trucks Type 3S2 - 5 axle tractor-semi trailer
80,000 lbs.

5. Typical Legal Trucks
Type axle truck-full trailer
80,000 lbs.

6. Posting Signs

7. SU4 – 54,000 lbs. (WB 18)

8. SU5 – 62,000 lbs. (WB 22)

9. SU6 – 69,500 lbs. (WB 30)

10. SU7 – 77,500 lbs. (WB 30)

11. What is the issue? SHV’s legal under 1975 bridge formula
Yet concentrate legal weight in smaller area concentrating loading on bridges

12. Redi-Mix Truck Example

13. Bending Moment Comparison
Redi-Mix truck - 80,000 lbs
3S2 Tractor Semi-Trailer - 80K lbs:
bridge loading 46% greater than 3S2 for 40 on 50 ft. spans.

14. First State Bridge Posted for SHV

15. Weight Limit Reduced for Single Unit Vehicles Only

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

17. Enforcement Question
Do SHV limits affect log Trucks? FHWA Guidance – 4 or more axle log trucks that meet SHV models, the combination is subject to load posting requirements

18. Lost River, East Langell Valley Road
Built in Feet Long Foot Maximum Span “Good” condition

19. Sign Options

20. Conclusions
Education is needed on how to interpret the SHV load posting signs.
Education is needed to on how the SHV load posting signs affect 105,500 lb. CTP’s
While the unfactored load effects for the SU-4 and CTP 2B are essentially the same, the need to restrict is based on nationwide factors that are calibrated from WIM data. Legal vehicles are more common, and have more variance in weight than the permit loads.

21. The End!