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Abstract(s)
A Brisa encetou vĆ”rios projetos sob o tema pavimentos sustentĆ”veis, no qual se enquadra o presente trabalho, e que se inserem no Ć¢mbito da estratĆ©gia de sustentabilidade e implementaĆ§Ć£o do conceito de economia circular no seu setor da pavimentaĆ§Ć£o. Na Brisa, a reutilizaĆ§Ć£o de misturas betuminosas recuperadas (RA) de pavimentos demolidos tem sido realizada, principalmente, atravĆ©s da substituiĆ§Ć£o do material granular aplicado em camadas nĆ£o ligadas dos pavimentos ou, em camadas betuminosas de base e ligaĆ§Ć£o (atĆ© 15 %). Contudo, os trabalhos de manutenĆ§Ć£o dos pavimentos da rede Brisa ocorrem essencialmente na camada de desgaste (95 % da Ć”rea intervencionada em 2023) o que limita a potencial utilizaĆ§Ć£o das misturas betuminosas recuperadas. Dentro deste contexto o presente estudo tem como objetivo principal avaliar a
viabilidade e a influĆŖncia da reutilizaĆ§Ć£o de 20 % de RA, proveniente de uma camada de desgaste em betĆ£o betuminoso drenante em fim de vida Ćŗtil, numa nova camada de desgaste em betĆ£o betuminoso rugoso. Para se concretizar o objetivo definido foram estudadas onze misturas betuminosas do tipo AC 14 Surf (BBr), que na sua constituiĆ§Ć£o utilizaram, duas RA de proveniĆŖncia distinta (fraĆ§Ć£o 8/16 mm), dois betumes modificados com polĆmeros (PMB) e dois aditivos rejuvenescedores distintos: (i) aditivo sĆ³lido com rejuvenescedor adicionado por via seca Ć mistura betuminosa e (ii) um aditivo rejuvenescedor incorporado no betume pelo respetivo fornecedor. O estudo considerou a avaliaĆ§Ć£o do comportamento mecĆ¢nico e funcional das misturas betuminosas, fabricadas em laboratĆ³rio, aplicadas em trechos experimentais e em trechos piloto em autoestrada. Foi ainda efetuada a avaliaĆ§Ć£o da influĆŖncia dos aditivos no comportamento do betume extraĆdo
das misturas betuminosas. O estudo permitiu concluir que a reutilizaĆ§Ć£o de 20 % de RA numa mistura betuminosa com caraterĆsticas de desgaste para autoestrada Ć© exequĆvel face Ć tecnologia de produĆ§Ć£o de misturas betuminosas disponĆvel em Portugal, com comportamento mecĆ¢nico e funcional equivalente a uma mistura betuminosa rugosa produzida apenas com materiais virgens.
Brisa has initiated several sustainable paving projects, including this study, as part of its sustainability strategy and the implementation of the circular economy concept in the paving sector. At Brisa, the reuse of reclaimed asphalt (RA) from demolished road pavements was mainly done by replacing aggregates used in granular layers of road pavements or in bituminous base and binder courses (up to 15 %). However, maintenance work on the Brisa network's pavements takes place mainly in the wearing course (95 % of the area rehabilitated in 2023), which limits the potential use of reclaimed asphalt. With this in mind, the main objective of this study is to assess the feasibility and influence of reusing 20 % of the RA from an end-life porous asphalt used in the wearing course in a new gap-graded bituminous mixture used as a wearing course. In order to achieve the defined objective, eleven AC 14 Surf (BBr) bituminous mixtures were studied, containing in their composition two RA of different origin (fraction 8/16 mm), two polymermodified bitumenās (PMB) and two different rejuvenating additives: (i) a solid additive with rejuvenating agent added to the bituminous mixture by the dry process and (ii) a rejuvenating additive added to the bitumen by the respective supplier. The study evaluated the mechanical and functional behaviour of bituminous mixtures produced in the laboratory and used in test sections and pilot sections on highways. It also evaluated the influence of additives on the behaviour of bitumen extracted from bituminous mixtures. The study concluded that the reuse of 20 % RA in a bituminous mixture with wear properties for highways is feasible given the technology available in Portugal for the production of bituminous mixtures, with a mechanical and functional behaviour equivalent to that of a gap-graded bituminous mixture produced only from virgin materials.
Brisa has initiated several sustainable paving projects, including this study, as part of its sustainability strategy and the implementation of the circular economy concept in the paving sector. At Brisa, the reuse of reclaimed asphalt (RA) from demolished road pavements was mainly done by replacing aggregates used in granular layers of road pavements or in bituminous base and binder courses (up to 15 %). However, maintenance work on the Brisa network's pavements takes place mainly in the wearing course (95 % of the area rehabilitated in 2023), which limits the potential use of reclaimed asphalt. With this in mind, the main objective of this study is to assess the feasibility and influence of reusing 20 % of the RA from an end-life porous asphalt used in the wearing course in a new gap-graded bituminous mixture used as a wearing course. In order to achieve the defined objective, eleven AC 14 Surf (BBr) bituminous mixtures were studied, containing in their composition two RA of different origin (fraction 8/16 mm), two polymermodified bitumenās (PMB) and two different rejuvenating additives: (i) a solid additive with rejuvenating agent added to the bituminous mixture by the dry process and (ii) a rejuvenating additive added to the bitumen by the respective supplier. The study evaluated the mechanical and functional behaviour of bituminous mixtures produced in the laboratory and used in test sections and pilot sections on highways. It also evaluated the influence of additives on the behaviour of bitumen extracted from bituminous mixtures. The study concluded that the reuse of 20 % RA in a bituminous mixture with wear properties for highways is feasible given the technology available in Portugal for the production of bituminous mixtures, with a mechanical and functional behaviour equivalent to that of a gap-graded bituminous mixture produced only from virgin materials.
Description
Keywords
Highways Sustainable Pavements Reclaimed Asphalt Rejuvenators Circular Economy Autoestradas Pavimentos SustentƔveis Misturas betuminosas recuperadas Rejuvenescedores Economia circular