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ARS Home » Southeast Area » Auburn, Alabama » Soil Dynamics Research » Research » Publications at this Location » Publication #407408
Research Project: Sustaining Productivity and Ecosystem Services of Agricultural and Horticultural Systems in the Southeastern United States

Location: Soil Dynamics Research

Title: Effects of vertical load and inflation pressure on tire-soil interaction on artificial soil

Author
item ALKHALIFA, NISREEN - Iowa State University
item TEKESTE, MEHARI - Iowa State University
item JJAGWE, PIUS - Iowa State University
item Way, Thomas - Tom

Submitted to: Terramechanics Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/2023
Publication Date: 12/18/2023
Citation: Alkhalifa, N., Tekeste, M., Jjagwe, P., Way, T.R. 2023. Effects of vertical load and inflation pressure on tire-soil interaction on artificial soil. Journal of Terramechanics. 112:19-34. https://doi.org/10.1016/j.jterra.2023.11.002.
DOI: https://doi.org/10.1016/j.jterra.2023.11.002

Interpretive Summary: Traction and soil compaction from vehicle tires on soil are strongly influenced by the weight supported by the tire and by the tire air pressure. An experiment was conducted using an LT235/75R15 light truck radial tire. We investigated effects of the weight supported by the tire and the tire air pressure, on the dimensions of the tire footprint, on a horizontal flat rigid surface and on soil. The soil, a sandy soil, was "artificial," meaning mineral oil was used as its moisture. The results are expected to be useful in improving traction performance of tires and reducing tire-induced soil compaction.

Technical Abstract: Instrumented single tire testing was conducted on a horizontal flat rigid surface and loose artificial soil in a soil bin at the Iowa State University Soil Machine Dynamics Laboratory (SDML) using two levels of tire vertical load (6 kN and 8 kN) and three levels of tire inflation pressure (179 kPa, 241 kPa, and 283 kPa). Using the instrumented single tire SMDL measurement system, deflection and tire contact experiments on a rigid surface and artificial soil were conducted by applying vertical load on an LT235/75R15 light truck radial tire. Vertical load and inflation pressure were found to significantly (P < 0.05) affect the tire deflection and contact area on the rigid surface. For the tire on the rigid surface, lowering the tire inflation pressure by 37%, from 283 kPa to 179 kPa, resulted in 26% and 39% greater contact lengths for the 6 kN and 8 kN vertical loads, respectively, and the contact length differences were significant (P < 0.05). The same reduction in inflation pressure caused the contact width to increase by 9% and 12% for the 6 kN and 8 kN vertical loads, respectively, and the contact length differences were significant (P < 0.05). The 2-D contact area on deformable soil with an initial bulk density of 1.51 Mg/m^3 was significantly affected (P < 0.05) by tire inflation pressure for each load case, but no significant interaction effect was found between the vertical load and the inflation pressure. Increasing the load significantly affected the tire’s contact length on soil (P = 0.0010); however, reducing tire inflation pressure did not significantly increase the contact length on soil (P = 0.0609). The results also showed that the soil rut depth and tire-soil deformed volume increased by increasing the vertical load and lowering tire inflation pressure, however the differences were not significant at P = 0.05. The contact area on the soil surface was 3.3 times the contact area measured on the rigid surface. Developing a method to quantify tire-soil interface properties on deformable soil is better than the historically-used gross flat plate method, for evaluating low ground tire inflation technology effects in improving traction and reducing soil compaction.