The Effects of Implements of Husbandry "Farm Equipment" on Pavement Performance
(TPF-5/148)

Over the past few decades, there have been significant changes in both farm size and farm equipment. These factors, combined with a regulatory emphasis that has encouraged farmers to store manure as a liquid and apply it in a short time frame, have encouraged the farm equipment industry to produce larger manure hauling and application equipment. The shift to larger and heavier equipment has occurred at a faster rate than either pavement design technology or state regulatory structures could match. Today, equipment innovations such as steerable axles, flotation tires, and new tire designs are not reflected in state DOT regulations. This situation has led to the adoption of equipment and practices that, while complying with the letter of the law, may actually create more pavement damage. 

Many states in the Upper Midwest share similar concerns about heavy farm equipment, and the pooled fund study framework allows for these states to pool their resources and research some common issues. This project studies the effects produced by a variety of current heavy farm vehicles. The capabilities of MnROAD make the facility ideal as a national center for testing overweight vehicles from farming and a number of other industries. New test sections constructed for this research could be used for testing other types of equipment long after this project is complete. The basic framework for this research may be of interest to other industries such as tire manufacturers, logging trucks, mining vehicles, forage harvesting equipment, and other heavy farm equipment.

The objectives of this study are to determine pavement response under various types of agricultural equipment (including the impacts of different tires and additional axles) and to compare this response to that produced by a typical 5-axle tractor-trailer.