Best Practice for Oversized/Overweight Vehicles
Need statement 724
Heavy trucks cause local roads to deteriorate more quickly than passenger vehicles. Agencies are receiving increased requests for permits to allow Oversize/Overweight (OSOW) vehicles up to 104,000 pounds; these OSOW cause exponentially more damage to pavements and cause road failures. Roads are not designed to accommodate this repeated weight, especially in the heat.
Although several other earlier studies have been completed, this study should help address:
- Definition of an ESAL and how an 80,000lb truck’s load is distributed and how it affects pavement life.
- What impact an OSOW load (104,000lbs) has on a pavement compared to a legal load (80,000lbs); expressed in layperson terms.
- Illustration of how OWOS loads can be distributed to lessen the impact to a pavement’s life.
- The impact repeated heavy loads (i.e., haul route, wind farm construction, etc.) have on a pavement’s life.
Much of this information may be covered within Minnesota Truck-Weight Education Program (an MN LTAP program co-funded by LRRB).
The first component of OSOW is over-sized, which is sometimes forgotten about. When OS vehicles are permitted, agencies should consider the impacts these vehicles may have on geometrics and signs. Specifically, does the route for the OS permit require:
- Signs need to be temporarily relocated to provide adequate turning movements.
- Intersections need to be temporarily widened to accommodate these vehicles.
The study should evaluate cost/benefit analysis of permitting OSOW, identify what the cost is to the agency (and ultimately the taxpayer) versus the benefit to a hauler, address the economic impacts of the permit (to the agency and to the taxpayer), determine and illustrate what axle spacing requirements currently meet pavement design standards for 10-tons (knowing this spacing would help locals review permit requests), and develop information on how to communicate with elected officials and road users.
Suggested deliverables
- Basic review of how a vehicle load is distributed, ESALs, axle loads and impacts to pavement life.
- Synthesis of research related to cost/benefit analysis of heavy loads on roadways.
- Develop a road life consumption calculator based on an agency’s current cost of construction.
- Communication guide for sharing the impact of OSOW vehicles on local systems with users and elected officials.
Previous research
- Allowing 129,000-Pound Trucks on our Highways; What is the Cost? What are the Benefits?, 2018
- Assessing The Effects Of Heavy Vehicles On Local Roadways, 2014
- Cost/Benefit Study of Spring Load Restrictions, 2005
- Roads and Loads: Finding a Balance, 2006 video
Possible members for technical advisory panel
- Aaron VanMoer (Lyon County)
- Rich Sanders (Polk County)
- Tim Stahl (Jackson County
- David Kramer (Winona County)
- Jonathan Large (Mahnomen County)
- Guy Kohlnhofer, Dodge County
- Ben Worel (MnDOT)
- Joel Ulring (MnDOT)
- Tom Nelson, MN Truck-Weight Education instructor