基于岩性-结构的煤层底板突水危险性评价  

Evaluation of water inrush risk of seam floor based on lithology-structure

作　　者：孟召平[1,2] 张贝贝[1] 谢晓彤[1] 申正伟 何方俊 潘之德 

机构地区：[1]中国矿业大学煤炭资源与安全开采国家重点实验室,地球科学与测绘工程学院,北京100083 [2]三峡大学三峡库区地质灾害教育部重点实验室,湖北宜昌443002

出　　处：《煤田地质与勘探》2011年第5期35-40,共6页Coal Geology & Exploration

基　　金：国家重点基础研究发展计划(973计划)项目(2007CB209405);国家自然科学基金项目(4117214541030422);教育部高等学校博士学科点专项科研基金项目(20100023110003);神华集团科技创新项目(SHGF-11-08);煤炭资源与安全开采国家重点实验室自主研究课题(SKLCRSM10B06)

摘　　要：煤层顶底板突水危险性预测与评价是煤矿突水灾害防治的基础和依据。针对煤层底板隔水介质条件,分析了煤系岩石力学性质,煤层底板突水的岩性、结构和厚度特征,建立了煤层底板突水危险性评价理论和方法。研究表明:煤层底板隔水介质条件取决于隔水层岩性和断裂构造,随着底板泥岩含量增加,煤层底板隔水性能增高,但抗水压能力降低;随着断裂发育程度的增加,底板隔水层由完整结构、块裂结构到碎裂结构和松散结构,煤层底板抗水压能力和隔水性能均降低,突水危险性增大。煤层底板抗水压能力与煤层底板隔水层厚度密切相关,统计表明,煤层底板受的极限水压p与底板隔水层厚度h之间为2次幂函数关系。在传统突水系数的基础上考虑了隔水层的岩性和结构特征,提出了煤层底板突水危险评价分类;进一步根据水压Pw与岩体破裂压力Pc关系和水压Pw与最小主应力?hmin关系判断是否突水。Water inrush risk prediction and evaluation of seam roof and floor are the foundation of water inrush disasters prevention in coal mines.According to the waterproof medium conditions of seam floor,the mechanical properties of coal-measure rock and the lithology,structure and thickness of seam floor were analyzed,the theory and methods of water inrush risk evaluation of seam floor were founded.It is shown that the waterproof medium conditions of seam floor depend on the lithlogy of aquifuge and the structure.Water isolating of seam floor becomes better with the increase of shale percentage content,but the ability of resisting water pressure was reduced.The aquifuge of seam floor changes from complete structure and block structure to cataclastic structure and loose structure with the increase of the fault development.The ability of resisting water pressure and water isolating of the seam floor decrease,and the water inrush risk increases.The ability of resisting water pressure of seam floor and the thickness of the aquifuge of seam floor are closely related.Statistical analysis showed a second power functional relationship between the limit water pressure（p） of seam floor and the thickness of aquifuge of seam floor（h）.The lithology and structure characteristics of the aquifuge were considered.The classification of water inrush risk evaluation of seam floor was proposed.Whether water inrush occurs is judged according to the relationship between hydraulic pressure（Pw） and rock mass rupture pressure（Pc） and the relationship between hydraulic pressure（Pw） and the minimum principal stress（σhmin）.

关 键 词：煤层底板 岩性-结构 突水危险性 

分 类 号：TD741[矿业工程—矿井通风与安全]