The application of MICP (microbial-induced calcite precipitation) to clays has been restricted due to their low permeability and small pore size, which limit bacterial mobility. The authors proposed an injection method for introducing solutions into a silty clay for MICP in the pore space. Test results showed that injecting equal volumes of bacterial solution and cementation solution resulted in 200% soil strength. The soil strength was estimated using a miniature cone penetration test, which provided a continuous cone resistance profile. The strength profile of the improved samples clearly showed that the peak strength occurred at the top portion of the samples, which implied that bacteria and urease traveled through the soil and MICP occurred. After the injection, 70–90% of the soil volume was improved through MICP. An analysis of drainage solutions after a few days showed calcite precipitation, which indicated that the urease reaction was still active in the drainage. These results can conclude that MICP is applicable to silty clays with similar properties, such as low permeability, low pH, and small pore size.

MICP（微生物诱导方解石沉淀）在粘土中的应用受到限制，因为它们的低渗透性和小孔径限制了细菌的流动性。作者提出了一种将溶液注入粉质粘土中的注入方法，用于孔隙空间中的 MICP。试验结果表明，注入等体积的细菌溶液和胶结溶液可产生 200% 的土壤强度。土壤强度是使用微型锥体穿透试验估算的，该试验提供了连续的锥体阻力分布。改良样品的强度曲线清楚地表明，峰值强度出现在样品的顶部，这意味着细菌和脲酶穿过土壤并发生 MICP。注入后，70-90% 的土壤体积通过 MICP 得到改善。几天后对排水溶液的分析显示方解石沉淀，这表明尿素酶反应在排水中仍然活跃。这些结果可以得出结论，MICP 适用于具有相似特性的粉质粘土，例如低渗透性、低 pH 值和小孔径。