Application of Automatic Air Inflation Deflation Control System on a Manure Tanker to Prevent Excessive Soil Compaction

<abstract> <b>Abstract.</b> An Automatic Air Inflation-Deflation (AAID) control unit was evaluated on a manure tanker to determine the best combinations of load and tire inflation pressure and to optimize the tire operational parameters for moderate and uniform distribution of the contact pressure. The tire footprint was characterized in terms of rut depth and width and soil physical properties (moisture content and cone index). Cone index was used as an indicator of increased soil strength caused by the weight of the manure tanker. Cone index values were significantly lower for the undisturbed soil compared to the soil that had been trafficked by tanker tires for all treatments. It was also observed that, as load was increased, rut width increased. This would be due to the bulging of the tire sidewall making contact with the soil, and therefore increase in the width of the soil-tire contact area. Conversely, when inflation pressure was increased, rut width decreased significantly with increased inflation pressure. Rut depth at the center and edge was affected by both inflation pressure and load. The degree of soil deformation was also investigated and the comparison results between the tire pressure of 300 and 100 kPa at a high load showed that the adjusted tire pressure using the AAID control unit could reduce the rut depth by 47 and 23% at the tire lug centerline and edge respectively.