模拟海水环境下MICP固化滨海粉细砂的试验研究

MICP-Cemented Coastal Fine Sand in Simulated Seawater Environment

在模拟海水环境下采用微生物固化法来加固滨海粉细砂,并通过无侧限抗压强度试验、碳酸钙含量试验和微观结构分析,研究了尿素浓度对MICP固化滨海粉细砂砂柱的影响,同时对比分析了淡水环境下MICP固化粉细砂的效果.研究结果表明:在海水环境下MICP技术固化滨海粉细砂是有效的,砂柱试件的无侧限抗压强度与碳酸钙含量随着尿素浓度的增加先增大后减小,并且1 mol·L^(-1)尿素处理试件的加固效果最好;海水的弱碱性环境可促进巴氏芽孢杆菌的生长和繁殖,进而可形成大量的高活性脲酶,从而大大提高了微生物诱导碳酸钙沉积的效率.

In our report,the microorganism solidification method was used to reinforce the coastal fine sand in the simulated seawater environment,the unconfined compressive strength test,the calcium carbonate content test,and the microstructure analysis were performed to analyze the effects of urea concentration on the solidification of coastal fine sand pillars solidified by MICP technology.The results showed that the MICP technology is effective to solidify coastal silt fine sand in a seawater environment;the unconfined compressive strength and calcium carbonate content of the sand column specimen first increases and then decreases with the increase of urea concentration,and the 1 mol·L^(-1) urea treatment condition is obtained;the weakly alkaline environment of seawater promotes the growth and reproduction of Bacillus pasteurii,and then formed a large number of highly active urease,which greatly improves the efficiency of microorganisms in inducing calcium carbonate deposition.