中文摘要：

研究了不同浓度（0.5、1.5、2.5、3.5mol/L 和 4.5mol/L）的镁添加剂对微生物水泥基材料力学性能的影响，并结合 X 射线衍射和扫描电子显微镜分析了微生物水泥基材料内部形成的矿物成分和微观结构。结果表明：当镁添加剂浓度为 2.5 mol/L 时，微生物水泥基材料孔隙率最小，结构最为密实，抗压强度最高；镁添加剂浓度较低（0.5mol/L 和 1.5mol/L）时，在微生物水泥基材料内部形成的矿物主要是方解石和高镁方解石，形貌以花菜形为主；镁添加剂浓度较高（2.5、3.5mol/L 和 4.5mol/L）时，砂柱内部形成的矿物主要是单水碳钙石和菱镁矿，矿物形貌以球柱状为主。

英文摘要：

The influence of magnesium additive concentrations （i.e., 0.5, 1.5, 2.5, 3.5 mol/L and 4.5 mol/L） on the mechanical proper- ties of microbe cementitious material was investigated. In addition, the mineral composition produced by microbe and microstructure of microbe cementitious material was analyzed by X-ray diffraction and scanning electron microscopy. The results indicate that when the magnesium additive concentration is 2.5mol/L, the microbe cementitious material has the denser microstructure with the lower porosity. The compressive strength could be superior. When the magnesium additive concentration was rather low, the precipitated minerals induced by microbe in the microbe cementitious material were mainly calcite and Mg-calcite, and the morphology of pre- cipitated minerals appeared mainly cauliflower shape. However, the magnesium additive concentration is higher, the minerals were mainly monohydrocalcite and hydromagnesite, and the morphology was mainly ball cylindrical.