坚硬顶板条件下周期来压规律分析

Analysis of Periodic Pressure Law under Hard Roof Condition

某矿8#煤层1201综采工作面下位顶板坚硬难冒,顶板悬露面积大,分析工作面采场顶板形成"短悬臂梁-砌体梁"结构,开采过程中将出现悬臂梁周期性破断和砌体梁结构周期性失稳,二者共同决定工作面的来压显现规律,分别使工作面形成小周期来压和大周期来压,顶板来压显现强烈。通过数值模拟与支架的工作阻力实测方法验证了采场顶板形成"短悬臂梁-砌体梁"结构,分析得出工作面大、小周期来压步距及大周期来压期间动载系数,这与顶板"短悬臂梁-砌体梁"结构破断规律相吻合。

The lower roof of 1201 fully mechanized coal face of No.8 coal seam in a coal mine is hard and hard to fall. The hanging area of the roof is large. Has analyzed the structure of the ＂short cantilever beam-masonrybeam＂ of the stope roof of the working face.In the process of mining, the periodic breaking of the cantilever beam and the periodic instability of the masonry structure would appear, and they both decide the regularity of the pressure behavior of the coal face. They respectively lead to the small periodic weighting and big periodic weighting, and the showing of periodic roof weighting is strong. Through the numerical simulation and field measurement method of the working resistance of the support, the structure of the ＂short cantilever beam-masonry beam＂ has been verified, and the step of the periodic roof weighting and dynamic load factor of big periodic weighting has been achieved. It is consistent with the ＂short cantilever beam-masonry beam＂ roof structure fracture law.