The Lab Services include single purpose project that utilize standard processes or procedures according to ASTM and ASABE standards for the following testing:
- Gravimetric material moisture content
- Atterberg limits of soil (plastic, liquid)
- Soil compaction measurement (soil bulk density and ASABE standard cone penetration testing)
- Moisture density curve (Proctor mold test)
- Particle distribution using sieve method
- Shear strength tests (direct shear and triaxial tests)
- 2D and 3D Tire/Track-to-soil footprint
2025 Report Tire Artificial Soil Contact Properties from VF Tires of Self-Propelled Sprayer
Test summary: Standardized vehicle load and tire footprint data for self-propelled sprayers are currently lacking. SMDL standardized footprint testing highlights the agronomic benefits of adjusting tire inflation pressure and utilizing advanced tire technologies to manage soil compaction. Using Iowa State’s soil bin footprint method, the report showed that at 83 kPa, the Alliance VF750/60R46 tire (57 kN load) displayed a 5.2% larger footprint compared to the Goodyear LSW 800/55R46, resulting in a 3.7% reduction in soil rut depth. At 117 kPa (17 psi), the Alliance tire exhibited a 3.2% smaller contact area than the Goodyear tire. Reducing tire pressure from 117 kPa to 83 kPa led to shallower rut depths of 7.3% for the Alliance tire and 6.9% for the Goodyear tire. By evaluating tire soil footprint area and rut depth on cohesive-frictional artificial soil, this testing helps growers and manufacturers make informed decisions about tire technologies and inflation pressures for sprayer equipment, ultimately reducing soil compaction and enhancing crop yield.
Tire Artificial Soil Contact Properties Report from VF Tire of A Self Propelled Sprayer_2025
For details to arrange the services, contact the services operations supervisor: Mehari Tekeste (mtekeste@iastate.edu) (515-294-2464). Address: Soil and crop mechanics laboratory 3210 Sukup Lab, Ames, Iowa 50010).