Soil compaction patterns caused by off-road vehicles in eastern canadian agricultural soils

The interaction between vehicles and soils of varying properties and moisture contents can cause serious compaction and soil structure problems. This situation always confronts the farmer, who has to deal with the soil effects, and should be of foremost interest to agricultural machine manufacturers and dealers as well as other off-road vehicle users in order that they may employ the best vehicle configuration for various conditions.This study is oriented towards evaluating compaction behaviour under various loads, different soil conditions, number of passes, and tire sizes. Contour plots of change in dry density compared to the original density were obtained under the tire path cross sections for different loads, number of passes and soil moisture conditions.The increase in dry density change, determined for different numbers of passes, was sharp up to five passes and levelled off for further increases in the number of passes. Increase in dry density became as great as 30 pcf (0.48 g/cm³), illustrating the detrimental effect of repeated passes of a vehicle in the field.