APPLICATION OF LYSINIBACILLUS SPHAERICUS FOR CONCRETE CRACK HEALING USING DIFFERENT CALCIUM SOURCES

Author(s): Christine Farrugia (1), Ruben Paul Borg (1), Joseph Buhagiar (2), Liberato Ferrara (3)
Paper category: Proceedings
Book title: SynerCrete’18 International Conference on Interdisciplinary Approaches for Cement-based Materials and Structural Concrete
Editor(s): Miguel Azenha, Dirk Schlicke, Farid Benboudjema, Agnieszka Jędrzejewska
ISBN: 978-2-35158-202-2
e-ISBN: 978-2-35158-203-9
Publisher: RILEM Publications SARL
Publication year: 2018
Pages: 1053-1058
Total Pages: 6
Language : English

Abstract: Micro-cracks, which develop during the service life of reinforced concrete structures, reduce the durability of concrete through the penetration of fluids. Microbially-induced calcium carbonate precipitation occurs naturally in the presence of ureolytic bacteria which precipitate calcium carbonate (CaCO3) through urea hydrolysis. This deposition leads to the filling of micro-cracks and sealing of pores, reducing ingress of fluids into the concrete. The research aim was to assess the potential of Lysinibacillus sphaericus to precipitate CaCO3 on concrete
through urea hydrolysis. Lysinibacillus sphaericus was cultivated in vitro and induction of ICP through urea hydrolysis was tested on cement paste with two different calcium sources. The calcium precipitates where characterised by light microscopy, Scanning Electron Microscopy, Energy Dispersive Spectroscopy and Fourier Transform Infrared Spectroscopy. The study confirmed that MICP is induced successfully on concrete using Lysinibacillus sphaericus. Samples exposed to repeated treatment cycles of Lysinibacillus sphaericus in the
presence of a calcium source exhibited a more extensive and even coating of CaCO3 crystals on the surface confirming that repeated cycles of treatment are more effective in increasing the amount of CaCO3 deposition and therefore increasing crack healing capacity.

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