充填采煤弹性基础边界基本顶薄板破断规律

发布时间：2018-11-25 12:36

【摘要】：建立充填开采基本顶弹性基础边界弹性地基薄板力学模型,依据差分理论及主弯矩破断准则,研究充填体弹性地基系数kf、基本顶厚度h、弹性模量E及边界弹性基础系数k_m对基本顶主弯矩及破断规律的影响,得出:(1)k_f增大时,短边、长边超前煤壁区及充填区中点绝对值最大主弯矩M_b,M_d,M_o均减小,M_o降低幅度最大,M_b深入煤壁距离b增大;(2)E或h减小时,M_b,M_d,M_o及b减小;(3)k_m增大时,b减小,M_b,M_d,M_o均增大;(4)充填区基本顶主弯矩存在分化效应:kf越大或h,E越小,充填区最大主弯矩逐步向周边转移,非中点区主弯矩逐渐大于M_o,k_m对分化效应的影响甚微。充填条件下基本顶主弯矩大于极限弯矩时,起始破断位置为长边深入煤壁上表面或中部下表面。当kf较小、充实率较低且上覆载荷较大时,基本顶断裂类型有:(1)长边上表面→短边上表面→中部下表面;(2)长边上表面→中部下表面→短边上表面;(3)中部下表面→长边上表面→短边上表面。
[Abstract]:Based on the difference theory and the breaking criterion of the main bending moment, the elastic foundation coefficient (kf,) of the filling body is studied by using the boundary elastic foundation thin plate mechanics model of filling mining. The effects of elastic modulus E and boundary elastic foundation coefficient K / M on the principal bending moment and breaking law of the basic roof are obtained. The following conclusions are obtained: (1) when KF increases, the maximum absolute maximum principal moment Mb of short edge and long edge leading coal wall and filling area is obtained. The Md / M / O decreases, the M / O decreases the most, and the M\ +\ {# * $\}\ {\}\ (2) when the number of E or h is reduced, the number of M / W / M / D / M / s / b / s / s (4) there is differentiation effect in the basic top bending moment of filling area: the larger the kf or the smaller the HEU E, the bigger the maximum principal moment in the filling area is gradually transferred to the periphery, and the greater the main moment in the non-midpoint area is, the smaller the effect is on the differentiation effect. When the main bending moment of the top is greater than the ultimate moment under filling condition, the initial breaking position is the long edge deep into the coal wall surface or the middle bottom surface. When the kf is small, the enrichment rate is low and the overburden is large, the basic top fracture types are as follows: (1) the short edge surface of the long edge surface, (2) the short edge surface of the long edge surface, (2) the middle edge surface of the long edge surface, the short edge surface of the long edge surface; (3) the middle bottom surface has long edge surface and short edge surface.
【作者单位】：中国矿业大学(北京)资源与安全工程学院;中国矿业大学(北京)共伴生能源精准开采北京市重点实验室;
【基金】：国家自然科学基金资助项目(51234005,51504259) 中央高校基本科研业务费专项资金资助项目(2010QZ06)
【分类号】：TD32;TD823.7

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