1 引言 宁阳煤田东部的石屯煤矿,开采石炭二迭系山西组浅部3~#煤层,上层覆盖着一层厚0.1～1.00mm的灰色泥质页岩伪顶,富含植物化石,性软,抗压强度低,吸水性强,遇水则软化为泥。特别开采露头防水煤柱以下的第一个工作面时,由于第四系潜水随老顶粗砂渗流到伪顶,回采过程中,松软易碎,加之构造复杂,极易和直接顶一起冒落,给顶板管理增加了难度,常发生漏顶、冒顶, 1 INTRODUCTION The Shitun coal mine in the east of Ningyang coalfield excavated the shallow coal seam 3 ~ # of the Permian Carboniferous in Shanxi Province. The upper layer was covered with a gray shale pseudo-top with a thickness of 0.1 ~ 1.00mm and rich in plant fossils, Soft, low compressive strength, strong water absorption, water is softened to mud. Special mining outcrop waterproof pillars below the first face, the Quaternary dive with the roof of coarse sand percolation to the pseudo top, the recovery process, soft and fragile, combined with the complex structure, easy to fall together with the direct top , To increase the difficulty of the roof management, often happen drain top, roof fall,