远距离下保护层开采上覆煤岩体卸压效应研究

Research on Pressure-Relief Effect of Overlying Coal Rock Body Using Far Distance Lower Protective Seam Exploitation Method

运用计算机数值模拟方法,对远距离下保护层开采上覆煤岩体应力分布、被保护层卸压变形规律进行研究,得出下保护层开采被保护层应力分布特征、卸压范围、变形规律等.结果表明,下保护层开采后对被保护层可以充分卸压,卸压保护层角为50°左右,被保护层最大膨胀变形率为1.5%,被保护层产生膨胀变形使其透气性增大,创造煤与瓦斯共采的条件.研究成果应用于工程实践,取得了显著的技术经济效益.

Using numerical simulation method, we studied the stress distribution of overlying. coal rock body and the pressure-relief and deformation rules of protected coal seam under the situation of far distance lower protective characteristics, scope of pressure relief, seam exploitation, obtaining the stress distribution and deformation rules etc. Results indicate that the stress of protected strata is entirely relaxed after exploitation of lower protective seam. Pressure relief protective angle is about 50°, and the maximum swelling ratio of the protected strata reaches 1.5 %. The swelling deformation of protected seam produces rock fissures, making the permeability increased, which is beneficial for coal mining and gas extraction at the same time. Research results have been applied in practice engineering and obtained significant technical and economical achievements.