Size Limits (maximums)
98 feet, 5 inches
Second trailer length 29 feet
The following table compares the above limits with those of the ISTEA freeze for long double- trailer combinations tractors in the six affected States.
Maximum Cargo- Carrying Length (feet)
Maximum GVW (pounds)
95 -- 95 93 95 95
111,000 -- 105,500 137,800 129,000 129,000
Comply with Bridge Formula B
Idaho Montana Nevada Utah
Comply with Idaho Bridge Formula Comply with Bridge Formula B and MoU Comply with Bridge Formula B Comply with Bridge Formula B
The proposal complies with all length limits except California, but the 118,000/128,000-pound limits exceeds current GVW limits in Arizona, California, and Idaho. As it is being proposed as a demonstration project, the proposal recommends an evaluation procedure and criteria. However, there are no data on the amount and type of truck traffic now operating on this corridor nor its expected impact.
State TS&W Studies
The Montana DOT has commissioned a project on “Assessing the Impact on Montana's Highways of Adopting Canadian Truck Weight and Size Limits,” with Dr. J. Stephens, Montana State University. The completion date is estimated to be Spring 1996.
The first report produced from this work is, “The Impact on Montana's Interstate Bridges of Adopting Canadian Interprovincial Weight Limits,” by S. Patterson, May 4, 1995. Paraphrasing a May 17, 1995 letter from Dr. Stephens, this is a “single load event” study involving the bridge superstructure. Fatigue and accelerated deterioration effects are not considered. Paraphrasing the abstract from the report (referencing Canadian B-train loads) of the 845 bridges on the Montana interstate system, 88 percent “have the required capacity to carry the increased demands of the Canadian configurations. Simple span structures made of reinforced concrete, steel, and prestressed concrete all possess the required capacity to carry the increased load. Notably,