Influence of Magnesium Additive on Mechanical Properties of Microbe Cementitious Materials

Microbe cement is a new generation cement due to the ever increasing awareness of environmental protection. Microbe cement is a new strengthening material based on microbiologically induced precipitation of calcium carbonate. This paper presents the results from laboratory research on the influence of magnesium additive concentration (1.0mol/L, 3.0mol/L, 5.0mol/L and 7.0 mol/L) on the mechanical properties of microbe cementitious materials. In addition, the micro-morphology and microstructure of microbe cementitious materials were analyzed by scanning electron microscopy (SEM). The experimental results indicate that when the magnesium additive concentration was 1.0 mol/L, the compressive strength of microbe cementitious materials can reach up to 6.2MPa at an age of 12 days. The microstructure of microbe cementitious materials depends on the content of mineral produced by microbially induced precipitation.