厚松散含水层下薄基岩综放开采支架合理支护阻力确定

Determination of Reasonable Supporting Resistance of Fully-mechanized Top Coal Caving Supports in Thin Bedrock Under Thick Loose Aquifer

在厚松散含水层下薄基岩综放开采时,由于基岩厚度较薄,覆岩破坏无法形成砌体梁铰接结构,而是呈现出悬臂破断形式,当基岩顶板切落时容易引起强烈的矿压现象;同时松散含水层具有载荷传递的作用,可传递上覆表土层的载荷,因此,在回采期间极易发生压架、突水溃沙事故。为此,结合朱仙庄矿87采区的实际条件,依据矿山压力与岩层控制理论,采用理论分析和数值模拟的计算方法对支架合理工作阻力进行了研究,提出了支架工作阻力P为基岩顶板切落对支架的作用力P1和水压对基岩作用力P2的总和,研究结果表明:当支架工作阻力为8 000 kN时,可以保证工作面不发生压架、突水溃沙事故。

When conducting fully-mechanized sublevel caving mining on thin bedrock level under thick loose aquifer, the overlying strata is destroyed,and can not form a masonry beam hinged structure because of thin bedrock. It shows a suspension arm broken forms. When rock roof falls, it easily leads to a strong phenomena of rock pressure to surrounding rock. The loose aquifer has a function of load transfer, it can pass on the load of the overlying topsoil. Therefore supports break-offs and sand inrush of water inrush accident easily happens during the mining period. According to practical conditions in Zhuxianzhuang 87 district and the theory of mining pressure and strata control, reasonable support resistance was studied by using theoretical analysis and numerical simulation. It was proposed that the working resistance of support （P） is the sum of the bedrock roof cut off the force （P1） and water pressure of the bedrock force （P2） .The results show that it can guarantee the face does not occur supports break-offs and sand inrush of water inrush accident when the working resistance of support is 8 000 kN.