短壁连采工作面顶板运动规律研究
Study on Roof Movement Law of Shortwall Continuous Coal Mining Face
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摘要: 为了防止顶板大面积来压对采场造成冲击、优化开采引起的应力分布,针对榆家梁煤矿薄基岩厚表土层的赋存特点,在42209短壁连采工作面采取顶板全垮落法开采技术,实现了对短壁开采顶板管理,提出了工艺极限回采面积与应力极限回采面积概念。结果表明,回采引起的超前支承压力走向与侧向应力集中系数分别为3.4和2.1,据实测工艺极限回采面积为1 500 m2,应力极限回采面积为15 000 m2,对顶板采用"人工强制放顶+小步距自然垮落"的全垮落控制模式可有效保证回采工艺安全。Abstract: In order to prevent the bumping occurred by the large area roof weighting and to optimize the stress distribution caused by the coal mining, according to the deposition features of the thin base rock and thick overburden in Yujaliang Mine, the coal mining technology with full roof falling method was adopted in No.42209 shortwall continuous coal mining face, a conception of the technical limit mining area and the stress limit mining area were provided and roof control of the shortwall mi ning was realized. The results showed that the strike and side stress concentrated cofficients of the advance support pressure caused by the mining operation were 3. 4 and 2.1 individually. According to the site measurements, the technical limit mining area was 1 500 m2and the stress limit mining area was 15 000 m2. The full roof fa ling control mode with artificial forced roof falling + short distance natural roof falling applied to the roof could effectively ensure the safety of the mining technology.