IMPACT OF CHEMICAL ADMIXTURES ON BIO-BASED SELF-HEALING MORTAR

Author(s): Ali Amiri, Mahzad Azima and Zeynep Başaran Bundur
Paper category: Proceedings
Book title: Proceedings of the Final Conference of RILEM 253-MCI Microorganisms-Cementitious Materials Interactions Volume II
Editor(s): Alexandra Bertron and Henk Jonkers
ISBN: 978-2-35158-207-7 (Set)
ISBN: 978-2-35158-210-7 (Volume 2)
e-ISBN: 978-2-35158-206-0
Publisher: RILEM Publications SARL
Publication year: 2018
Pages: 533-542
Total Pages: 308
Language : English

Abstract: Due to its brittle nature, concrete can crack under stress, and these cracks are one of the main reasons for a decrease in service life of concrete structures. Recent researches propose that it might be possible to develop a smart cement-based material that could self-heal the microcracks through biomineralization. Limited research on biomineralization in cement-based systems have shown promising results and suggested that the permeability could be decreased via self-healing. While this is encouraging, yet there is not enough information regarding the influence of admixtures on self- healing and long-term durability of the biogenic CaCO3. In this study, the microorganisms were introduced to cement paste with its growth media without any encapsulation. With this approach, the flexural cracks on mortar surface were sealed with CaCO3, the water absorption of the healed specimens was decreased compared to the cracked samples. The self-healing ability was found to be higher in presence of superplasticizers while air entraining agents (AEA) slightly decreased the sealing of the cracks. The precipitate, was found to be durable against rain and freeze-thaw cycles. However, the resistance of CaCO3 against sunlight was lower than its resistance to other weathering conditions.

Online publication : 2018
Publication type : full_text
Public price (Euros) : 0.00