微生物诱导碳酸钙沉淀改良黄土的崩解性试验研究  

Experimental Study on Disintegration Properties of Microbially Induced Calcite Precipitation Modified Loess

作　　者：许天驰 张浩男 贾苍琴[1] 王贵和[1] XU Tianchi;ZHANG Haonan;JIA Cangqin;WANG Guihe(School of Engineering and Technology,China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]中国地质大学(北京)工程技术学院,北京100083

出　　处：《硅酸盐通报》2023年第2期674-681,707,共9页Bulletin of the Chinese Ceramic Society

基　　金：中国地质大学(北京)2021年研究生创新基金项目(ZD2021YC059);中国地质大学(北京)大学生创新计划(202211415013)。

摘　　要：黄土特殊的结构和矿物组成导致其遇水易崩解,并引起边坡失稳、湿陷性沉降等一系列岩土工程问题。微生物诱导碳酸钙沉淀(MICP)技术是一种新型微生物矿化技术,本文通过自制崩解仪探究了养护龄期和胶结液浓度对MICP改良黄土崩解时间和崩解率的影响,根据非饱和土的单值有效应力公式,从孔隙水压力和孔隙气压力的角度建立了非饱和土崩解的力学模型,利用推导出的崩解率-时间公式拟合黄土试样的崩解曲线。结果表明:MICP改良试样的崩解率均低于未改良的试样;随着养护龄期增加,0.6 mol/L胶结液改良黄土的崩解时间由12 min增加到28 min;养护14 d时,MICP改良黄土的崩解率达到最低值0.02%,崩解率-时间公式对崩解率曲线的调整拟合优度均在0.90以上。The special structure and mineral composition of loess lead to its easy disintegration in water, and lead to a series of geotechnical engineering problems such as slope instability and collapsible settlement. Microbially induced calcite precipitation(MICP) technology is a new microbial mineralization technology. In this paper, the effects of curing age and cementing fluid concentration on the disintegration time and disintegration rate of MICP modified loess were investigated by means of self-made disintegration instrument. Based on the single value effective stress formula of unsaturated soil, the mechanical model of unsaturated soil disintegration was established from the view of pore water pressure and pore air pressure. The disintegration rate-time formula was used to fit the disintegration curves of loess samples. The results show that the disintegration rate of MICP modified samples are lower than unmodified samples. With the increase of curing age, the disintegration time of 0.6 mol/L cementing liquid modified loess increases from 12 min to 28 min. After curing for 14 d, the disintegration rate of MICP modified loess reaches the lowest value of 0.02%, and the adjusted goodness of fit of the disintegration rate-time formula to disintegration rate curve is above 0.90.

关 键 词：微生物诱导碳酸钙沉淀技术 黄土 崩解性 微分方程 孔隙气压力 曲线拟合 

分 类 号：TU414[建筑科学—岩土工程]