Estudo comparativo técnico-econômico entre métodos de dimensionamento de pavimentos asfálticos novos: Método do DNER e Método de Dimensionamento Nacional

Abstract

In the present work two methods of asphalt pavement design were studied, the empirical method developed by the extinct DNER, which is currently the most used in the country, and the National Dimensioning Method (MeDiNa), which uses the empirical-mechanistic methodology and represents an evolution important for road engineering projects. In addition to the referred methods of design, the New System of Reference Costs of Works (SICRO), a result of more than a decade of studies and presented in 2017 by DNIT, was studied, bringing significant methodological innovations to the budgets through its manuals and composition reports of costs. At first, two structures with different configurations were sketched by the two methods, using traffic data provided by DNIT in the BR-392/RS km 338 and volumetric flow information of the National Traffic Counting Plan, located at BR-287/RS km 301.6. Then, the budget of the structures was done through SICRO, calculating the cost per N of each structure. Subsequently, the structures dimensioned by the DNER method were analyzed through the MeDiNa software, verifying the true cost per N of these pavements and making a proper comparison with the structures dimensioned by MeDiNa in terms of durability and cost per N. Finally, a sensitivity analysis was performed with the structure of pavement dimensioned by MeDiNa which presented the best technical-economical result, where the class of asphalt concrete was first varied and, in a second moment, the level of reliability of the design, being evaluated the impacts of these alterations and the answers they bring to the pavement in technical and economic terms. In conclusion, it was evident the importance of MeDiNa for the construction of pavement structures with satisfactory performance, meeting the needs of the project, since the DNER method contains limitations that can lead to early pavement rupture. In addition, MeDiNa provides the construction of more economical structures in the long term, avoiding wastage of the public resources destined to this end. Another important result of this study was the improvement in the cost-benefit of the pavement with the use of asphaltic concrete of better quality, which provides economic advantage by enabling the implementation of pavements with thinner layers of coating