为研究大倾角放顶煤上覆岩层活动规律,以唐山矿0291工作面为对象,通过分析大倾角工作面上覆岩层顶板结构失稳过程,得到上覆岩层产生压裂性失稳后向高位转移的判别条件。研究结果表明:在0291工作面的砂岩顶板中,上位岩层的挠曲下沉虽会伴随裂隙及离层发生,但在结构失稳前几乎保持层面水平运动;上覆岩层的岩性与挤压角是保持上覆岩层结构稳定的主要因素,且挠曲下沉量与挤压角的增大会使结构更易发生压裂性失稳;上覆岩层回转角与挤压角的正比关系是上覆岩层结构产生压裂性失稳后向高位转移的关键,当结构产生压裂性失稳垮落后采空区得到不断充填,高位岩层的回转角与挤压角变小,结构开始趋于稳定状态。

In order to study the activity law of the overlying strata of the steep angle caving coal seam,the0291 working face of Tangshan Mine was taken as the object.By analyzing the instability process of the overlying strata roof structure on the steep angle working face,the discriminant conditions for maintaining the stabilityof the overlying strata structure and for the structure to shift towards high position after fracturing instability areobtained.The research results show that in the sandstone roof of the 0291 working face,the bending and sinking of the overlying strata may occur along with cracks and separation layers,But before the structural instability,it almost maintains horizontal motion at the level;The lithology and compression angle of the overlying strataare the main factors that maintain the stability of the overlying strata structure,and an increase in the deflectionsettlement and compression angle will make the structure more prone to fracturing instability;The proportionalrelationship between the rotation angle and compression angle of the overlying strata is the key to the transfer of92the overlying strata structure to the high position after fracturing instability.When the structure experiencesfracturing instability and the backward goaf is continuously filled,the rotation angle and compression angle ofthe high position strata decrease,and the structure begins to tend to a stable state.

关书方,杨长益,师皓宇,等 .大倾角放顶煤上覆岩层结构失稳力学机理研究[J].华北科技学院学报,2023,20(4):29-34

GUAN Shufang,YANG Changyi,SHI Haoyu,et al.Study on mechanical mechanism of structural instability ofoverlying rock strata in large dip angle caving coal[J].Journal of North China Institute of Science and Technology,2023,20(4):29-34