CARBON SOURCE SELECTION FOR MICROBIAL CONVERSION TO MINERALS IN CEMENTITIOUS MATERIALS

Author(s): Renee M. Mors and Henk M. Jonkers
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: 445-454
Total Pages: 308
Language : English

Abstract: Microbial conversion of a mineral precursor compound can be used to foster carbonate formation in cracks, automatically limiting water permeation. Carbon sources can be used as mineral precursor compound. Bacterial spores, activation nutrients and carbon sources compose the healing agent to add to cementitious materials as an additive. As the carbon source makes up the majority of the healing agent, this paper proposes criteria for selection of carbon sources. First, soluble organic carbon sources were selected from available literature on the effect on cement hydration. These carbon sources were related to the ability for microbial respiration of selected bacterial strains. Next, the carbon sources were compared to the list of allowed substances in the European norm on admixtures. Carbon sources were selected that indicated limited effect on cement hydration, positive microbial respiration and were allowed as additive. For the selected carbon sources the limited effect on cement hydration was verified by isothermal calorimetry. Ability for bacterial respiration was confirmed by various oxygen consumption methods for the component with the least inhibiting effect on cement hydration. Furthermore, the ability for mineral formation was shown in solution. This selection validated the choice for lactate and its derivatives as a carbon source for microbial healing in concrete.

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