Civil Engineering

Permanent URI for this collectionhttps://hdl.handle.net/10679/312

Browse

Browsing by Subject "Bacteria"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Placeholder
    Book PartPublicationMetadata only
    Bacteria-based concrete
    (Elsevier, 2018) Belie, N. de; Wang, J.; Bundur, Zeynep Başaran; Paine, K.; Civil Engineering; BUNDUR, Zeynep Başaran
    Several strains of bacteria can induce the precipitation of calcium carbonate, if the appropriate conditions, sufficient nutrients and a calcium source are provided. The metabolic pathway that is followed by the bacterial strain will dictate the type of nutrients to be selected. This precipitation ability has been investigated during recent decades to improve the mechanical properties and durability of construction materials. Starting with applications for the consolidation of natural stones in weathered cultural heritage buildings and the consolidation of sandy soils, the research efforts have moved towards applications in concrete. When bacteria are mixed into fresh concrete, viable cell numbers rapidly decrease with time. Still, positive effects on concrete strength have been reported. To improve the survival rate of bacteria in concrete, various encapsulation and immobilization strategies have been explored and bacterial spores have been used instead of vegetative cells. Furthermore, added nutrients may impair concrete properties and may also be encapsulated for this reason. Encapsulated bacterial spores have shown the ability to self-heal cracks in concrete and first in-situ applications have been launched.
  • Placeholder
    ArticlePublicationMetadata only
    Use of pre-wetted lightweight fine expanded shale aggregates as internal nutrient reservoirs for microorganisms in bio-mineralized mortar
    (Elsevier, 2017-11) Bundur, Zeynep Başaran; Kirisits, M. J.; Ferron, R. D.; Civil Engineering; BUNDUR, Zeynep Başaran
    Interest in developing bio-based self-healing cement-based materials has gained broader attention in the concrete community. One of challenges in developing bio-based self-healing cement-based materials is that cell death or insufficient metabolic activity might occur when the cells are inoculated to the cement paste. This paper investigates the use of internal nutrient reservoirs via pre-wetted lightweight fine expanded shale aggregates to improve cell viability in mortar. Incorporation of internal nutrient reservoirs resulted in an increase in the vegetative cells remaining without any substantial loss in strength. These results pave the way to develop a self-healing and self-curing concrete with an extended service life.