Abstract: Grouting curtain closure is one of the main technical means for deep mine water damage control. The objec-tive of this study was to solve the mine water damage problems in No. 8 coal seam of Zhuxianzhuang coal in Huaibei mining area. The CT scan and laboratory test were used to obtain the fracture distribution and rock me-chanics charac-teristics of the conglomerate. In addition,two numerical models of pore media and pore-single fracture media in the conglomerate layer were established using COMSOL Multiphysics software. Also,the grouting curtain closure effect was analyzed. The results show that the range of slurry transport in the porous medium increases with the increase of grou-ting time,and the diffusion range of the stabilized slurry is 10. 12-10. 44 m. In the pore single fracture medium,theslurry preferentially enters the fracture channel and then diffuses into the pore medium along the fracture direction. With the increase of grouting time,the slurry transport range gradually increases and eventually stabilizes. The longitu-dinal diffusion range of slurry is 10. 05-10. 23 m,and the transverse diffusion range is 16. 30-16. 98 m. According to the numerical calculation results,20 m is selected as the spacing of grouting holes in the site curtain grouting project, two rows of staggered grouting holes are arranged,and the curtain wall with an effective width of about 40 m is estab-lished. Finally,with the comparative analysis of physical-mechanical properties of conglomerate before and after grou-ting and the method of on-site water release test,it is verified that the curtain wall closure effect is good and the spac-ing of the grouting holes is reasonable.