海水环境下MICP加固珊瑚砂试验

Experiments of coral sand reinforcement using MICP in seawater environment

在模拟海水环境中使用尿素水解菌ATCC11859(巴斯德芽孢杆菌)进行微生物诱导碳酸钙沉积(MICP)水溶液试验和浸泡法加固珊瑚砂砂柱试验,研究海水环境对微生物诱导碳酸钙沉积的加固效果。水溶液试验表明,海水环境会抑制MICP过程中碳酸钙的最终生成量;浸泡法试验进一步表明,试样在加固相同时间时,海水环境下加固试样的无侧限抗压强度低于淡水环境下加固的试样;随着时间的增长,砂柱试样在海水环境下的无侧限抗压强度不断增加。

In a simulated seawater environment,urea-hydrolyzate strain ATCC11859(Bacillus pasteurii)was used to conduct microbial-induced calcium carbonate precipitation(MICP)aqueous solution tests and immersion method to reinforce sand column.The reinforcement effect of seawater environment on the microbial-induced calcium carbonate precipitation was investigated.The results of the aqueous solution experiments show that the seawater environment inhibits the final production of calcium carbonate during the MICP process.The immersion tests further show that the unconfined compressive strength of the strengthened specimens in seawater environment is lower than that in freshwater environment when specimens are reinforced for the same time.With the growth of time,the unconfined compressive strength of sand column samples in seawater environment is increasing.