Biocementation of Simulant Martian Regolith

摘要

Here on Earth biocementation has been extensively studied and holds promise in producing a more energy efficient and environmentally benign alternative construction materials compared to the standard method of production. This research is focused on developing bioprocesses to produce bioconcrete columns using potentially Mars-compatible microalgae and simulated Martian regolith. A marine microalga, Thraustochytrium striatum, was tested to make Martian regolith-based columns in the presence of CaCl2/urea.;Three different biogrouting methods were investigated including simultaneous, sequential and batch circulation of microalga cell biomass and CaCl2 /urea in the columns. The need of post-biogrouting column soaking was studied to develop an understanding of its relationship with unconfined compressional strength (UCS) of the columns. X-ray diffraction (XRD) was used to identify the formation of CaCO3 along with using a scanning electron microscope (SEM) to identify the microstructure of the deposited CaCO3. Carbonite titration analysis and hydraulic conductivity tests were conducted to further characterize the biocemented columns.