【摘要】 在薄基岩风氧化带下煤层开采易发生出水压架事故,为了保证薄基岩煤层的安全开采,以淮南顾北煤矿薄基岩煤层1512(3)工作面为研究背景,通过数值计算、理论分析、实验室试验及现场实测的方法研究了不同岩层结构对薄基岩采场覆岩运移规律的影响,提出了地面对工作面上方的基岩风氧化带进行预注浆加固方法并成功进行了试验。研究得出:松散含水层载荷传递作用下,当采场覆岩中只有单承载岩层时,顶板易出现大范围的下沉,工作面压架几率较高,而当采场有双承载岩层时,压架几率大幅减小;地面预注浆能够有效提高基岩风氧化带岩层整体强度,提高其承载能力;工作面来压步距大于类似条件下未注浆的工作面,且实现了工作面安全回采。更多还原

【Abstract】 Mining coal seam adjacent to weathering bedrock is easily to induce accidents such as water flushing. In order to ensure the safety during mining coal seam with thin bedrock, the 1512(3) working face of Gubei coal mine with thin bedrock is taken as the research objective. The influence of different rock strata structure on overburden strata movement with thin bedrock are investigated by using numerical calculations, lab testing and field measurements. The method of ground pre-grouting reinforcement for weathering bedrock over the coal seam is proposed and the application is successful. It is concluded that: under the load transfer of loose aquifer, coal seam, the roof tends to a large subsidence when there is only a single hard rock layer in overburden strata. The possibility of pressure racking is very high while it is significantly reduced when there are two or more hard rock layers existing. The ground pre-grouting application can effectively improve the overall strength and carrying capacity of the weathering bedrock. After grouting, the weighting interval is greater than the one before grouting under similar geological conditions. The longwall panel has been safely recovered.更多还原