PROPERTIES AND MICRO-STRUCTURAL ANALYSIS OF ORGANIC COMPOUND-ENRICHED SELF-HEALING CONCRETE
Certain additives to concrete mixtures, such as bacteria and organic compounds, have beenshown to affect concrete strength and/or self-healing properties. However, the likely inducedconcomitant materials micro-structural changes have not been clarified so far. Structuralchanges are possibly the result of differences in cement hydration processes whichaccordingly change the material properties. In the present experimental study it was foundthat different types of organic compounds, added to the concrete mixture as potential biomineral precursor compounds, strongly affected concrete strength properties. Although mostadded 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 strengthproperties. Micro-structural analysis by ESEM microscopy revealed the formation of calcite-like minerals which formation was presumably mediated by concrete-incorporated alkaliphilicbacteria. The simultaneous incorporation of bacteria and suitable organic bio-mineralprecursor compounds may thus result in a concrete with high self-healing properties, assecondary produced minerals can plug and seal freshly formed cracks. Additional microstructural properties, i.e. paste composition and permeability characteristics of bacteria and/ororganic compound-enriched concrete are currently being investigated by XRD andpermeability analyses.
Henk M.Jonkers Erik Schlangen
Microlab,Delft University of Technology,Faculty of Civil Engineering and Geosciences,Delft,The Netherlands
国际会议
南京
英文
243-252
2008-10-13（万方平台首次上网日期，不代表论文的发表时间）