Optimum tire pressure for legal axle loads on Egyptian roads

الملخص EN

In recent years, the effect of increased truck-axle load on pavement performance has become a subject of great concern under the allowance of increasing the limits of legal axle loads.

So, the purpose of this study is to investigate the effect of increased truck-axle load and tire pressure on the pavement life with respect to fatigue and rutting, to recognize the optimum truck-tire pressure for the recommended truck-axle loads in Egypt.

Ten axle loads levels ranging from 16-kip to 34-kip and from 20-kip to 56-kip for single and tandem axles, respectively, along with ten levels of tire contact pressure ; 80-psi to 170-psi are investigated in this study.

The used methodology is based on the damage analysis concept which performed for both fatigue cracking and rutting using KENLAYER program.

The study results showed that pavement life with respect to rutting is mainly related to the magnitude of the axle load, while fatigue life is mildly related to the magnitude of both tire pressure and axle load.

Also, the equilibrium between fatigue and rutting lives is found at heavy axle loads associated with high tire pressure or at light axle loads associated with low tire pressure.

The study also, concluded that the heavy axle load should associate with high tire pressure for optimum utilization of pavement section.

Finally, the study recommended optimum truck-tire inflation pressure of 140 and 120-psi at the value of the legal axle load in Egypt for single axle and tandem axle, respectively.