Demonstration projects with self-healing capsule-based and bacteria- based concrete

Author(s): Nele De Belie, Maria Araujo, Tim Van Mullem, Elke Gruyaert
Paper category: Proceedings
Book title: SynerCrete’18: Interdisciplinary Approaches for Cement-based Materials and Structural Concrete: Synergizing Expertise and Bridging Scales of Space and Time Vol. 1 & 2
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: 29-38
Total Pages: 10
Language : English

Abstract: To reduce downtime, costs and labour for repair of concrete structures, self-healing concrete has been proposed as a solution. Over the last decade, the efficiency of different self-healing mechanisms has been tested at laboratory scale. Lately, the first demonstrators have been made in order to test the self-healing efficiency at real scale and in actual service conditions. At the one hand our team has cast real-scale concrete beams, containing previously selected polymeric capsules. As capsule wall material, poly(methyl methacrylate) (PMMA) was chosen due to its high chemical stability in contact with concrete, high survival ratio during the concrete mixing process and ability to rupture when crossed by cracks of small width. The self-healing efficiency of the concrete elements with randomly dispersed PMMA capsules was determined after crack creation by 3-point-bending tests.
Secondly, an in situ demonstration project was established with microbial self-healing concrete. A mixed ureolytic culture of bacterial spores (MUC+) and the nutrients urea and calcium nitrate were mixed into the concrete in a real concrete plant. With this self-healing concrete the roof plate of a sewer inspection pit was cast. From the same batch of concrete, prisms were taken to the laboratory for crack creation and evaluation of the self-healing efficiency. For cracks with an average width of 348 μm, created after 6 weeks of curing, a sealing efficiency against water flow of more than 90% was measured after 24 weeks of water immersion.

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