1. School of Resource and Safety Engineering,China University of Mining and Technology (Beijing),Beijing　 100083,China; 2. Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources,China University of Mining and Technology (Beijing),Beijing　 100083,China

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。

Under the condition of filling coal mining,a thin plate mechanics model of main roof on elastic foundation with elastic foundation boundary was established. According to the difference theory and the fracture principle of pri- mary bending moment,the effects of the elastic foundation coefficient kf of filling body,the thickness h and elastic modulus E of the main roof and the elastic foundation coefficient km of boundary on the primary bending moment and fracture regularity of the main roof were studied. It is concluded that when the kf increases,the absolute maximum prin- cipal bending moment of the short side and long side ahead of the coal wall and the filling area Mb ,Md and Mo all de- crease,while the Mo decreases most,and the distance b of Mb ahead of the coal wall increases. When E or h decreases, the b and the Mo ,Mb and Md all decrease. When the km decreases,the b decreases,whlie the Mb ,Md and Mo increase. In the filling area,the principal bending moment of main roof has differentiation phenomenon. The larger the kf ,or the smaller the h and E,the maximum principal bending moment of the filling area is gradually transferred to the surround- ing area. The principal bending moment in the non-midpoint region is more than Mo . The km has little effect on the differentiation phenomenon. Under the filling conditions,when the principal bending moments of main roof is greater than the ultimate moment of main roof,the initial fracture position is the upper surface of the long side leading coal wall or the middle lower surface of main roof. When the kf is small,the filling rate is low and the overlying load is large,there are three types of main roof fracture sequence:① upper surface of long side→upper surface of short side→lower sur- face of the middle;② upper surface of long side→lower surface of the middle→upper surface of short side; ③ lower surface of the middle→upper surface of long side→upper surface of short side.

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)；

XIE Shengrong,CHEN Dongdong,GAO Mingming,et al. Fracture regularity of thin plate model of main roof with elastic foundation bounda- ry for backfill mining[J]. Journal of China Coal Society,2017,42(9):2270-2279.