Impact on pavement deterioration due to overload vehicle regulation in Brazil

Abstract

The investments required to maintain pavement conditions during its life-cycle are directly connected to the fleet weigh spectrum. Recently, Brazilian authorities have agreed on increasing trucks overloading enforcement tolerance – from a 7.5% maximum overweight per axle to 10%, despite maintaining the gross vehicle weight (GVW) to a maximum of 5%; this allowed heavier axles and, therefore, increased road owner cost to maintain functional parameters within expected limits. To evaluate the impact of the observed overload on pavement deterioration and, specifically, due to the new regulation, an assessment on the pavement’s life cycle alteration was carried out using the traffic load spectrum obtained during the year of 2017 in a weighting station located on the BR-116 (Rio Grande do Sul State). The HDM-4 models were applied in order to obtain the pavement deterioration and to conduct an economic evaluation for a 30-year life-cycle cost analysis considering four scenarios: (i) no overload tolerance; (ii) new overload regulation – 10% tolerance enforced on the axle-load weight limits; (iii) actual axle-loads spectrum – including overloaded axles. The scenario with the actual axle-loads resulted in a considerable impact in the LCCA in terms of Net Present Value (NPV), what reinforces the need of a better inspection of vehicle loads in order to preserve the pavement investments.