Reforço de pavimentos: análise das soluções de projeto da RSC-287 através do MeDiNa

Abstract

Brazil's traditional pavement reinforcement design methods are based on maximum pavement deflection and empirical parameters that were determined after observations of some materials in specific regions and temperatures. The DNER PRO-11/79 procedure standard is still the most used pavement reinforcement method used in ongoing projects, however, with the constant increase in traffic, the reinforcements projected by this standard are no longer enough and usually present faults due to fatigue before the end of the design period. Therefore, through the Asphalt Technology Network, made up of Petrobras, ANP and some Brazilian universities, a new National Method of Pavement Design, the "MeDiNa", was prepared, which is awaiting DNIT approval. This method gave rise to a software also called "MeDiNa. In its penultimate testing version was incorporated a function that allows to analyze and design reinforcement of pavements. For the reinforcement, the software has as main criterion of analysis the cracked area by fatigue at the end of the project period, being 30% the maximum accepted value. Based on this, the present study aimed to analyze the RSC-287 rehabilitation project, which was prepared for the CREMA-RS Program, whose service instruction basically follows the DNER PRO-11/79 standard. For this, each homogeneous segment of the project was analyzed in the MeDiNa software with 4 classes of asphalt concrete that come pre-established in the computational program. The segments that presented a cracked area greater than 30% were redesigned by the software. A calculation of the volume of asphalt concrete required for the reinforcement with the 4 classes was carried out and a comparison was made with the volume of the original design. Also, a comparison was made with the work of Maboni (2018), who did a similar analysis, but at the time the software still did not offer the option of pavement reinforcement. In addition, a comparison of the useful life of each homogeneous segment was made in the absence of reinforcement design. The solutions that predicted only milling and recomposition with the same thickness presented worse results than those that predicted discontinuous milling and addition of reinforcement layer. The results also showed that the analysis is very sensitive to the type of asphaltic concrete, where the ones with higher resilience modulus and better fatigue coefficients showed longer life.