微生物固化砂土的研究进展

RESEARCH PROGRESS OF BIO-CEMENTED SAND

微生物诱导碳酸钙沉淀（MICP）是一种新兴的土体加固改良技术,该技术具有高效、环保和经济的特点。MICP通过将微生物引入到岩土工程中,利用微生物诱导碳酸钙改善土体的物理力学性能。近年来,生物岩土技术逐渐成为岩土工程的一个热门研究方向。从微生物诱导碳酸钙沉淀的基本原理出发,归纳总结MICP反应中影响因素（细菌、营养液成分、pH、温度和固化方式）对生物固化砂土的影响,阐述生物固化土的岩土工程性质（渗透性、强度、耐久性、液化性、扫描电镜和X射线衍射微观机理）和工程应用（砂土改良、污染土修复、混凝土裂缝修复和飞尘抑制）。通过对国内外MICP方向的文献整理和归纳,探讨MICP发展方向和存在的问题。

Microbial Induced Calcium Carbonate Precipitation（ MICP） is an emerging reinforcement technique for soil reinforcement that is highly efficient,environmentally friendly and economical. MICP enhances the physical and mechanical properties of soils by introducing microbes into geotechnical engineering and using microbial induced calcium carbonate. In recent years,bio-geotechnical technique has gradually become a hot research direction of geotechnical engineering. Based on the basic principle of microbial-induced calcium carbonate precipitation,the paper summarized the influence of influencing factors（ bacteria,nutrient solution composition,pH,temperature and curing method） on the bio-cured sand in the MICP reaction. The geotechnical properties of bio-cemented soils（ permeability,strength,durability and liquefaction,SEM and XRD microscopic mechanisms） and engineering applications（ sand improvement,remediation of contaminated soils,restoration of concrete cracks and suppression of fly ash） were described. Through the literature reviewing and summarizing the MICP directions at home and abroad,it is hoped that MICP will be further studied.