微生物加固土体的反应-运移模型及数值模拟  

Reactive-transport model and numerical simulation of microbially induced carbonate precipitation

作　　者：曾晨 姚翔川 郑俊杰[1] 徐智韬 ZENG Chen;YAO Xiangchuan;ZHENG Junjie;XU Zhitao(School of Civil and Hydraulic Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;CCCC Second Harbor Engineering Company Ltd.,Wuhan 430040,China)

机构地区：[1]华中科技大学土木与水利工程学院,湖北武汉430074 [2]中交第二航务工程局有限公司,湖北武汉430040

出　　处：《华中科技大学学报（自然科学版）》2021年第12期105-111,共7页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家重点研发计划资助项目(2016YFC0800200);国家自然科学基金资助项目(51878313).

摘　　要：基于微生物加固(MICP)技术的作用机理,考虑注浆(包括菌液和胶结液的注入)过程中细菌的运移和附着、尿素水解速率、碳酸钙沉淀、孔隙填充和渗透率降低等特征,建立了适用于现场尺度的反应-运移模型.结合实际工程中的注浆方案,模拟分析了注菌(即注入细菌悬浮液)和注胶(即注入胶结液)速率及注胶方式对固化效果的影响.结果表明:注菌速率的增加会降低细菌的固定率;在单一注胶方式下,注胶速率的增加能提高反应物的运移效率,改善碳酸钙沉淀的均匀性,但是不利于碳酸钙沉淀量的累积;采用循环注胶方式并提高胶结液浓度,能增加细菌和反应物的利用率及运移效率,在增加碳酸钙累积量的同时改善固化的均匀性.Based on the mechanism of microbially induced carbonate precipitation(MICP),considering the transport and fixation of bacteria,ureolysis reaction rate,precipitation of calcium carbonate,the reduction of porosity and permeability during the injection(including injection of bacteria and substrates),a reactive-transport model at the field-scale was established.Combined with the injection strategies of field cases,the model was used to study the effect of injection rates of bacteria and substrates and injection methods of substrates on the performance of MICP treatment.The results indicate that the increase of bacterial injection's flow rate decreases the fixation ratio of bacteria.By using the single injection method,the increase of substrates injection's flow rate can enhance the efficiency of substrates transport and improve the homogeneity of calcium carbonate distribution with relatively lower accumulation of calcium carbonate amount.By using the cyclic injection method with higher substrates concentration,the utilization and transport efficiency of bacteria and substrates are enhanced effectively,increasing the amount of calcium carbonate precipitation while improving the homogeneity of treatment.

关 键 词：微生物加固 现场尺度模拟 反应-运移模型 参数分析 数值模拟 

分 类 号：TU43[建筑科学—岩土工程]