氧化镁-微生物与微生物诱导碳酸盐沉淀固化尾矿砂效果的试验研究

Study on Cementation Effect of Tailing Sand by Magnesium Oxide Combined with Microorganism or by MICP

将氧化镁与微生物结合运用到尾矿砂固化中,并与微生物诱导碳酸盐沉淀(MICP)相对比,通过无侧限抗压强度和扫描电镜试验,探究尾矿砂初始含水率(范围在16%~25%)和氧化镁掺量(范围在6%~15%)以及MICP中尾矿砂初始含水率(范围在16%~25%)对固化效果的影响。结果发现,在氧化镁-微生物固化尾矿砂中,初始含水率越高,试样无侧限抗压强度越低;氧化镁掺量越多,强度越高;在MICP过程中,随着初始含水率的增加,试样强度先降低后增高,最低点的初始含水率为19%。

Magnesium oxide combined with microorganism was used to cement tailing sand, and a comparison between cementation effect of maguesium oxide combined with microorganism and microbial induced carbonate precipitation(MICP) was conducted. The effects of the initial moisture content(in the range of 16% to 25%) of tailing sand and the magnesium oxide content(in the range of 6% to 15%), and the initial moisture content(in the range of 16% to 25%) of tailing sand during MICP on cementation were explored by unconfined compressive strength and SEM tests. The results showed that in the process of cementation with magnesium oxide combined with microorganism, the higher the initial moisture content was, the lower the unconfined compressive strength was;and the more the magnesium oxide content was, the higher the strength was;and in MICP, with the increase of the initial moisture content, the strength of specimens first decreased and then increased, and the lowest initial moisture content was 19%.