Centro de Território, Ambiente e Construção
Escola de Engenharia da Universidade do Minho
Campus de Azurém
4800-058 Guimarães, Portugal
Phone: + 351 253 510 200 (517 206)
Fax: + 351 253 510 217
Email: geral@ctac.uminho.pt
@JournalArticle {2570, title = {Suitability of different foamed bitumens for warm mix asphalts with increasing recycling rates}, journal = {Construction and Building Materials}, volume = {142}, year = {2017}, month = {2017-07-01 00:00:00}, pages = {342 - 353}, publisher = {Elsevier}, abstract = {Due to the current need for more sustainable production processes and construction materials, foamed bitumen has become one of the most interesting solutions for asphalt paving works, both for new (warm mix) and recycled asphalt mixtures (warm recycled mix). However, significant work still needs to be carried out in order to fully understand the performance of foamed bitumens, and their adequacy for incorporation into asphalt mixtures with different amounts of reclaimed materials, which is the main objective of this work. Three types of bitumen, with increasing penetration grades were selected in order to evaluate their foaming properties, namely their expansion ratio and half-life, as well as the foam index assessed using the foam decay curves obtained through a semi-automated process. After determining the most suitable composition of each foamed bitumen (water content, temperature, foam stabilizing additive content), these were incorporated into asphalt mixtures with 0\%, 30\% and 50\% reclaimed asphalt material. As the amount of reclaimed material increased, the penetration grade of the new bitumen added was also increased, in order to compensate the lost properties of the aged binder. The suitability of these solutions was assessed through water sensitivity tests, and it was concluded that the proposed approach is adequate to obtain long-lasting solutions. Moreover, it became evident that foamed bitumens perform better when incorporated into recycled asphalt mixtures.
}, keywords = {Asphalt mixtures, Decay curves, Expansion ratio, Foam index, Foam stabilizing additive, Foamed bitumen, Half-life, Recycling, Water sensitivity}, issn = {0950-0618}, doi = {10.1016/j.conbuildmat.2017.03.085}, url = {http://www.sciencedirect.com/science/article/pii/S0950061817304580}, author = {Abreu, L. P. F. and Oliveira, J. R. M. and Silva, H. M. R. D. and Palha, D. and Fonseca, P. V.} }
The Centre for Territory, Environment and Construction (CTAC) is a research unit of the School of Engineering of University of Minho (UMinho), recognised by the “FCT – Fundação para a Ciência e Tecnologia” (Foundation for Science and Technology), associated to the Department of Civil Engineering (DEC), with whom it shares resources and namely human resources.
Currently CTAC aggregates 25 researchers holding a PhD of which 20 are faculty professors of the Civil Engineering Department. Read more
Centro de Território, Ambiente e Construção
Escola de Engenharia da Universidade do Minho
Campus de Azurém
4800-058 Guimarães, Portugal
Phone: + 351 253 510 200 (517 206)
Fax: + 351 253 510 217
Email: geral@ctac.uminho.pt