STUDY OF ASPHALT SELF-HEALING WITH COLORLESS BINDER AND PIGMENTED OIL

• Autor(a) principal: Ribeiro, Tiago Letras
• Data de Publicação: 2022
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/155799
• topic: Encapsulated rejuvenator; Asphalt self-healing; Pigmented oil; Calcium alginate capsules; Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Civil

Encapsulated rejuvenators are an innovative solution to improving the durability of asphalt pavements, which can result in roads that are cheaper to maintain and have a small environmental footprint. One technique for creating these encapsulated rejuvenators uses sodium alginate, that can be produced from seaweed, sunflower seed oil, and a simple laboratory process to form calcium alginate capsules with pockets of oil, the rejuvenator, inside. One of the ways that more can be learned about this technology is by studying its working mechanism, which is typically done with complex techniques, such as computed tomography scans or infrared spectroscopy. They are then combined with mechanical testing. While extremely useful, such techniques require expensive equipment and are typically limited to smaller samples. This work aimed to find an alternative method for observing the encapsulated rejuvenator's behavior in asphalt. By combining light-colored asphalt made with a synthetic binder and pigmented oil capsules, the rejuvenator's propagation was studied visually. To achieve this, a suitable pigment had to be found and calcium alginate capsules containing colored oil had to be produced, along with light-colored asphalt. These materials had to be tested and understood before a set of tests was devised to study the rejuvenator's behavior in asphalt. Overall, findings showed that oil and pigment release was limited and lacked uniformity. The solubility of vegetable oil in synthetic binder was also limited when compared to bitumen. Asphalt concrete mixtures with capsules showed more instances of pigment/oil release than comparable stone mastic asphalt mixtures.