【作者】 王晓振；

【导师】 许家林；

【作者基本信息】 中国矿业大学 ， 采矿工程， 2012， 博士

【摘要】 我国华东、华北等矿区内煤系地层普遍被第四系巨厚松散层覆盖，该松散层底部存在着一层以非胶结沙土、砂砾、砾石为骨架的承压含水层，邻近该松散承压含水层的工作面在开采过程中，曾发生多起压架突水灾害。以皖北祁东煤矿为例，直接赋存于基岩上部的松散含水层的平均厚度为35~50m，静水水压达3~4MPa。自2002年投产以来，该矿相继在8个工作面发生了17起压架突水事故，严重影响了矿井的正常生产，造成了巨大的经济损失。针对松散承压含水层下采煤压架突水灾害问题，论文综合运用理论分析、数值模拟与物理模拟试验、现场实测等手段，就松散承压含水层下采煤压架突水灾害的发生机理、发生条件及防治对策等进行了深入的研究。通过理论与模拟实验研究，揭示了松散承压含水层下采煤压架突水灾害的产生机理，得出松散承压含水层的载荷传递作用导致一定覆岩条件的关键层结构发生整体破断是引发上述压架突水灾害的根本原因。研究掌握了松散承压含水层骨架特征、覆岩关键层结构、主关键层结构稳定性等因素对工作面压架突水的影响规律。当含水层骨架以粗颗粒砂砾为主时，含水层厚度越大、渗透性能越好，载荷传递系数越大，覆岩关键层越容易发生复合破断。在含水层载荷传递系数较大的情况下，如果覆岩中存在坚硬岩层，那么基岩厚度越小、煤层上方10倍采高范围内存在厚硬岩层、煤层上方第1层硬岩层厚度越大时，覆岩容易发生整体复合破断导致压架事故，此时主关键层一般处于失稳状态，顶板导水裂隙异常发育并沟通含水层，引发突水灾害。为实现松散承压含水层下工作面的安全开采，研究形成了“危险区域预测—水位预警—实时调控”的灾害防治技术体系。根据压架突水灾害的发生条件，提出了松散承压含水层下采煤工作面压架突水危险区域的预测方法，即首先确定含水层载荷传递系数，在该系数较大的情况下，再根据钻孔柱状判断易发生复合破断的区域，即压架突水的危险区域；针对危险区域内工作面的安全开采，提出基于关键层位置的顶板预裂爆破和采用高阻力支架等措施来防范压架突水灾害；在工作面开采过程中，基于长观孔水位与顶板来压的联动效应，结合地下水动力学原理，计算出压架突水灾害的临界水位降速预警值，对灾害进行实时预警，并通过支护质量监测、采煤速度调控等措施来避免压架突水灾害的发生。松散承压含水层下采煤压架突水灾害发生条件及防治对策的研究成果，在祁东煤矿6130、7121等工作面得到了成功的应用，实现了上述工作面的安全开采，挽回直接经济损失1270万元，创造直接经济效益7862.8万元，社会、经济效益显著。更多还原

【Abstract】 There is a layer of unconsolidated confined aquifer with high water pressure which forms with unconsolidated sand and grit at the bottom of thick quaternary topsoil in some east china north china coalmine. In recent years, some coalmines have occurred several accidents as supports crushing and water inrushing when mining under such unconsolidated confined aquifer. Take Wanbei Qidong coal mine as an example. It exist unconsolidated confined aquifer at the top of bedrock with thickness of35to50meters and water pressure3to4million Pa. Science mining from2002year, it has happened17accidents as supports crushing and water inrush, and has caused a serious threat to coal mine production safety and significant economic losses. Further research on occurring condition and disaster prevention skills of support crushing and water inrush accident during mining under unconsolidated confined aquifer were studied totally by theoretical analysis, numerical simulation, physical simulation, field measurements etc.According to theoretical and simulated experiment research, we reveal the mechanization of support crushing and water inrush disaster during mining under unconsolidated confined aquifer. The key strata within a certain condition are prone to compound breakage under the effect of load transfer of the unconsolidated confined aquifer, which is the basic reason of support crushing and water inrush disaster. The influence law of characteristic of unconsolidated confined aquifer, key stratum structure and primary key stratum structure stability to the support crushing and water inrush disaster. Larger the skeleton granule diameter is, better the property of flowing and replenishment is, larger the load transfer quotient is, it easily makes the key stratum compound breakage. While under the large load transfer of the unconsolidated confined aquifer, smaller the overburden thickness and larger the first key stratum above coal seam is, more easily the overburden forms compound single key structure, especially existing thick and strong rock in10times mining height, which is prone to caused support crushing and water inrush disaster. The key stratum is usually in an unstable condition and water flowing fracture develops anomaly and connect to the aquifer, which caused water inrush disaster.Aim to realize safe mining under unconsolidated confined aquifer, form a technical route of’dangerous area detecting, water level warning, real-time regulate and control’ Forecasting method of dangerous area of support crushing and water inrush disaster and retaining safety coal and rock pillar are put forward according to occurrence condition of support crushing and water inrush disaster. Put forward roof pre-blasting based on location of key stratum and high resistance support to preventing support crushing and water inrush disaster before mining. Using the connected effect between water level variation of loose unconsolidated confined aquifer and roof weighting of working face, the forecasting method using descending speed of groundwater level for support crashing and water inrush disaster was put forward, And using support quality monitoring and mining velocity regulate and control during mining to prevent support crushing and water inrush disaster.Research results of condition and prevention of support crushing and water inrush disaster during mining under unconsolidated confined aquifer have being used successfully at NO.6130and7121working face in Qidong coal mine, which realizes the safe mining, retrieve a loss of12,700,000Yuan and create economic benefits of78,628,000Yuan. Achieve remarkable social and economic benefits.This paper contains83Figures,22tables and171references.更多还原