Effect of Tire Parameters on Pavement Damage and Load‐Equivalency Factors

Abstract

The effects of tire pressure, tire type, axle load, and axle configuration are investigated under actual truck loading and highway speed on instrumented test sections. The various tire types are tested against the 11R22.5 tire to evaluate their relative damage to pavements. The wide‐base single tires consistently have significantly higher strains and deflection than dual tires. The fatigue and rutting damage factors for the wide‐base single tires range from 1.5 to 1.7 and from 1.2 to 2.0 for the single and tandem axles, respectively. Three groups of load equivalency factors (LEF's) are also developed; 10% and 45% fatigue and rutting LEF. The LEF's for the wide‐base tires are higher than the dual‐tire LEF's by 50% and 70% for single and tandem axles, respectively. The American Association of State Highway and Transportation Officials (AASHTO) LEF's are higher than the singleaxle LEF's calculated from this study, while they compare favorably with the tandem‐axle LEF's. However, tire type, axle load, and axle configuration have significant effects and cannot be ignored in the avement‐design process.