Properties and micro-structural analysis of organic compound-enriched self-healing concrete

Title: Properties and micro-structural analysis of organic compound-enriched self-healing concrete
Author(s): H.M. Jonkers, E. Schlangen
Paper category : conference
Book title: International Conference on Microstructure Related Durability of Cementitious Composites
Editor(s): W. Sun, K. van Breugel, C. Miao, G. Ye and H. Chen
Print-ISBN: 978-2-35158-065-3
e-ISBN: 978-2-35158-084-4
Publisher: RILEM Publications
Publication year: 2008
Pages: 243 - 252
Total Pages: 10
Nb references: 15
Language: English

Abstract: Certain additives to concrete mixtures, such as bacteria and organic compounds, have been shown to affect concrete strength and/or self-healing properties. However, the likely induced concomitant materials micro-structural changes have not been clarified so far. Structural changes are possibly the result of differences in cement hydration processes which accordingly change the material properties. In the present experimental study it was found that different types of organic compounds, added to the concrete mixture as potential biomineral precursor compounds, strongly affected concrete strength properties. Although most added organics led to a mild to severe reduction in compressive strength, some compounds, like the amino acids glutamate and aspartate, resulted in equal or even increased strength properties. Micro-structural analysis by ESEM microscopy revealed the formation of calcitelike minerals which formation was presumably mediated by concrete-incorporated alkaliphilic bacteria. The simultaneous incorporation of bacteria and suitable organic bio-mineral precursor compounds may thus result in a concrete with high self-healing properties, as secondary produced minerals can plug and seal freshly formed cracks. Additional microstructural properties, i.e. paste composition and permeability characteristics of bacteria and/or organic compound-enriched concrete are currently being investigated by XRD and permeability analyses.

Online publication: 2009-06-09
Publication type : full_text
Public price (Euros): 0.00