西北黄土覆盖区采煤地裂缝造成浅表水资源漏失和土体失稳，为此开展黄土覆盖区采煤地裂缝微生物诱导碳酸钙(CaCO3)沉淀(Microbial Induced Carbonate Precipitation，MICP)修复实验研究。以陕北柠条塔煤矿为研究背景，对采煤地裂缝特征进行观测，揭示采煤地裂缝发育特征。结合矿山压力观测，划分黄土采煤地裂缝类型。基于采煤地裂缝分类和特征，采用无侧限抗压实验、三轴抗压实验、变水头渗透实验及三轴渗透实验，对比测试了两类裂缝黄土MICP修复样品的力学和水理参数。基于修复体pH、MICP CaCO3产量和扫描电镜测试结果，剖析采煤地裂缝MICP修复影响因素。结果表明：黄土覆盖区采煤地裂缝可分为边界地裂缝和内部地裂缝2种类型。边界地裂缝条件下，菌液和胶结液的最佳比例为1.2∶1.0。内部地裂缝条件下，裂缝充填物中风积沙与黄土的最佳比例为1∶1，菌液和胶结液的最佳比例为1∶1。黄土覆盖区不同类型采煤地裂缝的开度差异，造成CaCO3产率相差31.2%，因此，边界地裂缝较内部地裂缝最佳MICP修复液中胶结液成分所占比例更大。裂缝充填物中风积沙与黄土为1∶1时，充填物与修复液混合体的pH为9.2。该pH环境CaCO3产率可达88%，促进了MICP高效运行。研究成果为黄土覆盖区采煤地裂缝修复提供了参考。

The coal mining induced ground fissures in the loess covered area of northwest China cause shallow groundwater resource leakage and soil instability. Therefore, the experimental study was conducted on Microbial Induced Carbonate Precipitation (MICP) restoration of coal mining induced ground fissures in the loess covered area. Specifically, the characteristics of mining induced ground fissures were observed and their development characteristics were revealed based on Ningtiaota Coal Mine in northern Shaanxi. The coal mining induced ground fissures in loess were classified with consideration to the observed mine pressure. Based on the classification and characteristics of coal mining induced ground fractures, the mechanical and hydraulic parameters of two types of MICP-treated loess fissure samples were compared and tested using the unconfined compression tests, triaxial compression tests, variable head permeability tests and triaxial permeability tests. In addition, the influencing factors of MICP restoration for coal mining induced ground fissures were analyzed based on the pH value of the restoration body, MICP calcium carbonate production, and scanning electron microscopy test results. The results indicate that coal mining induced ground fissures in loess covered areas can be divided into two types: boundary ground fissures and internal ground fissures. In terms of boundary ground fissures, the optimal ratio of bacterial solution to cementitious fluid is 1.2∶1.0. For the internal ground fissures, the optimal ratio of wind-blown sand and loess to fill the fissures is 1∶1, and the optimal ratio of bacterial solution and cementitious fluid is 1∶1. The difference in the opening of different types of coal mining induced ground fissures in loess covered areas results in a 31.2% difference in the yield of calcium carbonate. Therefore, the optimal MICP restoration solution for boundary ground fissures has a larger proportion of cementitious fluid compared to internal ground fissures. When the ratio of wind-blown sand and loess in the filling material is 1∶1, the pH value of the mixture of filling material and restoration fluid is 9.2, and the yield of calcium carbonate in such pH value environment can reach 88%, promoting the efficient operation of MICP. The research results provide a reference for the restoration of coal mining induced ground fissures in loess covered areas.