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Publication Date

Fall 2012

Degree Type

Thesis - Campus Access Only

Degree Name

Master of Science (MS)


Civil and Environmental Engineering


Laura Sullivan-Green


crack dating, crack's age

Subject Areas

Civil engineering


An approach to quantify sparse biomass on construction materials was the main focus of this study. The purpose of this study was to verify the applicability of previously developed visualization and quantification techniques on mixed culture biofilms as a foundation for determining a crack's age in building materials with the help of biomass accumulation. Mixed culture biofilms were cultivated on non-porous surfaces, fed through the use of a stationary feeding technique, and evaluated through the use of confocal laser scanning microscopy. Being able to determine the approximate timing of occurrences of such cracks could potentially save millions of dollars each year in reduced frivolous insurance claims, legal fees, and insurance premiums.

Experiments were performed using two representative mixed bacterial communities at different nutrient concentrations. Results from the experiments substantiated the case for biological crack dating by establishing the applicability of these methods for mixed bacterial communities. Future work involves verifying the applicability of these methods for more diverse microbial colonies, varying temperature conditions, and varying nutrient contents in order to develop these methods for non-optimal oligotrophic field conditions.