Abstract：The liquefaction induced in loose and saturated sand foundations by dynamic loading such as earthquakes and the “static” liquefaction induced during rainfall and groundwater rise in loose sand slopes can lead to catastrophic damages such as the subsidence of road embankments, landslides and the floating of embedded structures like pipelines and tunnels. Compared with the traditional ground improvement methods, one of advances in bio-mineralization enables the rapid microbial induced carbonate precipitation, which is introduced by transporting the bacterial cells and nutrient solutions into loose sand foundations for the purpose of ground improvement. This new ground improvement process is called bio-grouting. It is the leading edge of ground improvement research, which has many advantages such as small disturbance, short construction period, notable reinforcement and low energy consumption. This study is attempted to investigate whether the bio-grouting is applicable to the improvement of liquefiable ground through dynamic triaxial tests and shaking table tests. First, a brief introduction to the research, development of microbial induced carbonate precipitation and bio-grouting technology is presented, and a practical bio-grouting treatment method applicable to improvement of liquefiable sand foundations is described. Second, the anti-liquefaction performance and other dynamic performance of the bio-grouting sand ground are studied through dynamic triaxial and small scaled shaking table tests, and a comparison between the bio-grouting and the traditional ground improvement methods is made. The test results show that the anti-liquefaction performance of bio-grouting samples and models is greatly improved. In short, the bio-grouting technology has potential to be used in engineering applications and broad application prospect in liquefiable sand foundations.
程晓辉, 麻强, 杨钻, 张志超, 李萌. 微生物灌浆加固液化砂土地基的动力反应研究[J]. 岩土工程学报, 2013, 35(8): 1486-1495.
CHENG Xiao-hui, MA Qiang, YANG Zuan, ZHANG Zhi-chao, LI Meng. Dynamic response of liquefiable sand foundation improved by bio-grouting. Chinese J. Geot. Eng., 2013, 35(8): 1486-1495.
Towhata I. Geotechnical earthquake engineering[M]. Berlin: Springer Berlin-Heidelberg, 2008. Stocks-Fischer S, Galinat J K, Bang S S. Microbiological precipitation of CaCO<sub>3</sub>[J]. Soil Biology and Biochemistry, 1999, 31: 1563-1571. Castanier S, Le Metayer-Levrel G, Perthuisot J P. Ca-carbonates precipitation and limestone genesis-the microbiogeologist point of view[J]. Sediment Geology, 1999, 126: 9-23. Bang S S, Galinat J K, Ramakrishnan V. Calcite precipitation induced by polyurethane-immobilized Bacillus pasteurii[J]. Enzyme and Microbial Technology, 2001, 28: 404-409. Whiffin V S. Microbial CaCO<sub>3</sub> precipitation for the production of Biocement[D]. Western Australia: Murdoch University, 2004. Nemati M, Voordouw G. Modification of porous media permeability, using calcium carbonate produced enzymatically in situ[J]. Enzyme and Microbial Technology, 2003, 33: 635-642. WARREN L A, MAURICE P A, PARMAR N,et al. Microbially mediated calcium carbonate precipitation: implications for interpreting calcite precipitation and for solid-phase capture of inorganic contaminants[J]. Geomicrobiology Journal, 2001, 18: 93-115. Al-Thawadi S M. High strength in-situ biocementation of soil by calcite precipitating locally isolated ureolytic bacteria[D]. Western Australia: Murdoch University, 2008. Harkes M P, van Paassen L A, Booster J L,et al. Fixation and distribution of bacterial activity in sand to induce carbonate precipitation for ground reinforcement[J]. Ecological Engineering, 2010, 36: 112-117. Whiffin V S, Van Paassen L A, Harkes M P. Microbial carbonate precipitation as a soil improvement technique[J]. Geomicrobiology Journal, 2007, 24(5): 417-423. Van Paassen L A, Ghose R, van der Linden T J M,et al. Quantifying bio-mediated ground improvement by ureolysis: a large scale biogrout experiment[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2010, 136: 1721-1728. DeJong J T, Fritzges M B, Nusslein K. Microbially induced cementation to control sand response to undrained shear[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2006, 132(11): 1381-1392. Burbank M B, Weaver T J, Green T L,et al. Precipitation of calcite by indigenous microorganisms to strengthen liquefiable soils[J]. Geomicrobiology Journal, 2011, 28: 301-312. YANG Z, CHENg X H, LI M. Engineering properties of micp-bonded sandstones used for historical masonry building restoration[C]// ASCE Geo Frontiers 2011: Advances in Geotechnical Engineering. Dallas, 2011: 4031-4040. 沈吉云. 微生物成因土工材料实验及应用研究[D]. (北京:清华大学), 2009.(SHEN Ji-yun. Experiments and Applications of Bio-Geomaterials[D]. Beijing: Tsinghua University, 2009. (in Chinese)) Wei-Soon N, Min-Lee L, Siew-Ling H. An overview of the factors affecting microbial-induced calcite precipitation and its potential application in soil improvement[J]. World Academy of Science, Engineering and Technology, 2012, 62: 723-729. AL QABANY A, SOGA K, SANTAMARINA C. Factors affecting efficiency of microbially induced calcite precipitation[J]. ASCE Journal of Geotechnical and Geoenvironmental Engineering, 2012, 138: 992-1001. Martinez B C, Barkouki T H, DeJong J T,et al. Upscaling of microbial induced calcite precipitation in 0.5 m columns: experimental and modeling results[C]// ASCE Geo Frontiers 2011: Advances in Geotechnical Engineering. 2011: 4049-4059. van Wijngaarden W K, Vermolen F J, van Meurs G A M,et al. Modelling biogrout: a new ground improvement method based on microbial-induced carbonate precipitation[J]. Transport in Porous Media, 2011, 87(2): 397-420. Bachmeier K L, Williams A E, Warmington J R,et al. Urease activity in microbiologically-induced calcite precipitation[J]. Journal of Biotechnology, 2002, 93: 171-181. LI m, CHENG X H, GUO h x. Heavy metal removal by biomineralization of urease producing bacteria isolated from soil[J]. International Biodeterioration & Biodegradation, 2012, 76: 81-85. LI m, CHENG X H, GUO h x. Application of response surface methodology for carbonate precipitation production induced by a mutant strain of Sporosarcina pasteurii[C]// ASCE Geo Frontiers 2011: Advances in Geotechnical Engineering. Dallas, 2011: 4079-4088. 李 萌. 微生物诱导的土木工程加固与防渗机理研究[D]. 北京: 清华大学, 2011.(LI Meng. The microbial induced civil engineering reinforcement and impermeability mechanism research[D]. Beijing: Tsinghua University, 2009. (in Chinese)) 程晓辉, 杨 钻. 利用产尿酶微生物制备高强微生物砂浆的方法: 中国, 201210464480.8[P]. 2012.(CHENG Xiao-hui, YANG Z. High strength microbial mortar production and control method: China patent, 201210464480.8[P]. 2012. (in Chinese)) Van der Ruyt M, van der Zon W, JONES D. Biological in situ reinforcement of sand in near-shore areas[J]. Proceedings of the Institution of Civil Engineers- Geotechnical Engineering, 2009, 162: 81-83. Gallaghera P M, Mitchell J K. Influence of colloidal silica grout on liquefaction potential and cyclic undrained behavior of loose sand[J]. Soil Dynamics and Earthquake Engineering, 2002, 22: 1017-1026. Toru S, Hiroshi Y, Manabu M. Liquefaction process of sand during cyclic loading[J]. Japanese Society of Soil Mechanics and Foundation Engineering, Soils and foundations, 1972, 12(1): 1-16. Motamed R, Towhata I. Mitigation measures for pile groups behind quay walls subjected to lateral flow of liquefied soil: Shake table model tests[J]. Soil Dynamics and Earthquake Engineering, 2010, 30: 1043-1060.