This study explored the effect of microbially induced carbonate precipitation (MICP), a natural bio-geotechnical process, on mitigating the uneven settlement in electro-osmotic consolidation of soft soil. The real-time drainage and settlement were measured, and the control behavior of drainage to settlement was discussed. MICP solution components were also selected as the different additives to determine the control mechanism of MICP in improving settlement and reinforcement uniformity of clay. After the tests, the chemical properties and microstructure were analyzed according to pH, conductivity, and SEM. The addition of MICP solution in clay significantly even reduced the coefficient of settlement variation by 53.2%, and the upper surface profile tended to be uniform. Contrary to control, the coefficient of settlement variation of MICP-treated soil decreased gradually with drainage volume, mainly due to the filling of solid substances such as calcium carbonate, biofilm, and/or calcium hydroxide produced within soil pores. MICP significantly improved the uneven soil reinforcement generated during the electro-osmotic consolidation but resulted in the lower strength near the anode due to the less drainage. The contribution of MICP solution components to the improvement of settlement and strength uniformity obviously varies. Bacterial cells improved the settlement uniformity but had no effect on the strength improvement of soil. The co-existence of Ca²⁺ and bacterial cells maximized the modification effect, which determined the production of mineral precipitation. Microstructure observation proved the formation of calcium carbonate. The results demonstrated that MICP is an effective technique to improve the settlement and reinforcement uniformity of marine clay in electro-osmotic consolidation.

本研究探讨了微生物诱导碳酸盐沉淀 (MICP)（一种天然生物岩土工程）对减轻软土电渗固结中不均匀沉降的影响。实时测量排水和沉降，讨论排水对沉降的控制行为。还选择了MICP溶液组分作为不同的添加剂，以确定MICP在改善粘土沉降和增强均匀性方面的控制机制。测试结束后，根据pH值、电导率和SEM分析化学性质和微观结构。粘土中MICP溶液的加入甚至显着降低了53.2%的沉降变异系数，上表面轮廓趋于均匀。与控制相反，MICP处理土壤的沉降变异系数随着排水量的增加而逐渐减小，主要是由于土壤孔隙内产生的碳酸钙、生物膜和/或氢氧化钙等固体物质的填充。MICP显着改善了电渗固结过程中产生的不均匀土壤加固，但由于排水较少导致阳极附近强度较低。MICP溶液组分对改善沉降和强度均匀性的贡献明显不同。细菌细胞改善了沉降均匀性，但对土壤强度的提高没有影响。Ca的共存 MICP显着改善了电渗固结过程中产生的不均匀土壤加固，但由于排水较少导致阳极附近强度较低。MICP溶液组分对改善沉降和强度均匀性的贡献明显不同。细菌细胞改善了沉降均匀性，但对土壤强度的提高没有影响。Ca的共存 MICP显着改善了电渗固结过程中产生的不均匀土壤加固，但由于排水较少导致阳极附近强度较低。MICP溶液组分对改善沉降和强度均匀性的贡献明显不同。细菌细胞改善了沉降均匀性，但对土壤强度的提高没有影响。Ca的共存²⁺和细菌细胞使修饰效果最大化，这决定了矿物沉淀的产生。微观结构观察证明形成碳酸钙。结果表明，MICP是一种提高海相粘土电渗固结沉降和加固均匀性的有效技术。