Soil Improvement Using Microbial Induced Calcite Precipitation and Surfactant Induced Soil Strengthening
College of Computing, Engineering & Construction
Master of Science in Civil Engineering (MSCE)
NACO controlled Corporate Body
University of North Florida. School of Engineering
Dr. Raphael Crowley
Dr. Nick Hudyma
Dr. Craig Hargis
Dr. Osama Jadaan
Dr. William F. Klostermeyer
Microbially induced calcite precipitation (MICP) has been used for a number of years as a technique for the improvement of various geological materials. MICP has been used in a limited capacity in organic rich soils with varying degrees of success. Investigators hypothesized that microbially-induced cementation could be improved in organic soils by using a surfactant. Varying amounts of Sodium Dodecyl Sulfate (SDS) were added to soils of varying organic content and a mixing procedure was used to treat these soils via MICP. Treated specimens were tested for unconfined compressive strength (UCS). Results appeared to show direct relationships between SDS content and treated specimen strength although significant variability was present in the data. In addition, results also indicated that while addition of SDS during MICP treatment strengthens soil, the strengthening is likely from the formation of a calcium dodecyl sulfate (CDS) complex in which the CDS surrounds the soil in a matrix, and formation of MICP-induced calcite has very little to do with overall soil performance. As such, a new method for stabilizing loose soils dubbed ‘Surfactant-induced soil stabilization’ (SISS) was further explored by treating additional soil specimens. Samples treated using this technique showed increases in strength when compared to untreated specimens. In addition, preliminary data indicated that SISS treated specimens were insoluble. The SISS technique presents a number of advantages when compared to traditional soil stabilization techniques. In particular it should be relatively low-cost and simple to administer since its only components are SDS and calcium chloride. Additionally, these constituents are relatively more sustainable than chemicals associated with more-traditional loose soil stabilization techniques.
Davies, Matthew P., "Soil Improvement Using Microbial Induced Calcite Precipitation and Surfactant Induced Soil Strengthening" (2018). UNF Graduate Theses and Dissertations. 837.