A new technique of ground improvement by the microbial function has been recently proposed, in which soil cementation can be generated by adding calcium, nutrient and microbes into soil. Metabolic function of microbes produces carbon dioxide, which helps to generate calcium carbonate. In this study, a series of trial tests was conducted in order to evaluate the degree of soil cementation generated by those function in loose sand, using the measurement of shear wave velocities transmitted in a specimen. [This abstract is not included in the PDF]