多层坚硬顶板采场覆岩“拱壳”大结构形成机理研究

Study on formation mechanism of arch shell large structure of overburden in coal mining face with multi layer hard roof

为得到多层坚硬顶板采场覆岩"拱壳"大结构形成机理,以大同矿区同忻煤矿石炭系多层坚硬顶板特厚煤层开采为工程背景,基于关键层理论分析了同忻煤矿3-5煤层特厚煤层综放开采多层坚硬顶板的破断特征和大空间采场覆岩结构特征;应用弹性板理论,建立了大空间采场坚硬覆岩"拱壳"平衡大结构力学模型和数学模型。研究表明:坚硬覆岩"拱壳"平衡大结构理论,较好地揭示了同忻煤矿8105、8106等工作面开采过程中产生大小周期来压、采动影响范围大、易产生强矿压等特殊矿压现象的机理。研究成果为大同矿区石炭系坚硬覆岩特厚煤层开采工作面矿压控制提供理论依据。

In order to achieve the formation mechanism of the arch shell large structure of overburden in the coal mining face with the multi layer hard roof,taking the ultra thick seam mining with Carboniferous multi layer hard roof in Tongxin Mine of Datong Mining Area as an engineering background, based on the key stratum theory, the paper had an analysis on the breakdown features of the multi layer hard roof in the fully-mechanized ultra thick seam mining face in No. 3-5 seam of Tongxin Mine and the overburden structure features of the large space mining face. An elastic plate theory was applied to establish an arch shell balanced large structure mechanics model and the mathematical model of the hard overburden above the large space mining face. the study showed that the arch shell balanced large structure theo- ry of the hard overburden could be applied to well reveal the large and small periodic roof weighting,large mining influence scope, easy occurred strong mine rock pressure and other special mine rock pressure phenomenon mechanism occurred in the mining process of No. 8105, No. 8106 and other coal mining face in Tongxin Mine. The study results could provide the theoretical basis to the mine rock pressure control of the coal mining face in the ultra thick seam with Carboniferous hard roof in Datong Mining Area.