镁离子对微生物砂浆强度影响的研究

INFLUENCE OF MAGNESIUM ION ON THE STRENGTH OF MICROBIAL MORTAR

微生物诱导碳酸钙技术（MICP）应用于砖石类文物建筑修复时,提高微生物砂浆强度是较为重要的目标。之前的研究大多是针对酶活性、颗粒粒径级配、温度、p H值、钙盐种类及浓度等进行优化。为研究在引入微量镁离子后微生物砂浆固化过程中,微生物砂浆强度以及产物中碳酸钙的结晶形式的影响,对玻璃珠和石英砂的MICP砂柱进行胶凝试验。研究发现：微量镁离子的加入,使得试件的单轴无侧限抗压强度明显提高,碳酸钙中文石和球霰石的比例也相应提高。

To improve the strength of microbial mortar is a significant cement purpose when microbially induced carbonate precipitation（ MICP） technology is applied in the masonry relics building repair. Factors such as urease activity,particle grade,temperature,p H and calcium solution have been optimized in previous researches. In the paper,the strength of microbial mortar and the crystal form of calcium carbonate in the product after the introduction of trace magnesium ions in the MICP process were studied. Through the MICP cementation test of glass beads and quartz sand,it was found that the uniaxial compressive strengths of the samples increased obviously with the addition of trace magnesium ions,and the proportion of aragonite and vaterite in the product calcium carbonate increased accordingly.