College of Resources and Safety Engineering,China University of Mining and Technology (Beijing),Beijing　 100083,China

建立考虑两侧煤柱支撑与实体煤作为弹性基础的基本顶板初次断裂力学模型，采用差分算法及主弯矩破断准则计算研究得到如下结论。① 基本顶初始断裂位置为偏较弱煤柱侧悬顶区中部下表面(弹性基础系数k较小，基本顶厚度h、弹模E较大时)，反之为偏较弱煤柱侧的长边实体煤区上表面;② 两侧煤柱的宽度L1，L2及支撑系数km1，km2改变时，基本顶中部区与实体煤区的主弯矩及位置几乎不改变，而两侧煤柱区的主弯矩及位置变化显著;③ E，h大，而L1，km1，L2，km2小时，基本顶在两侧煤柱区不断裂，破断顺序为:偏较弱煤柱侧的悬顶区中部下表面→偏较弱煤柱侧长边实体煤区上表面，断裂特征为非对称“=-X”型;反之基本顶在煤柱区会断裂，破断顺序为:偏较弱煤柱侧长边实体煤区上表面→偏较弱煤柱侧悬顶区中部下表面→较强煤柱区上表面→较弱煤柱区上表面，断裂特征为非对称“O-X”型;而L1，km1较小，L2，km2较大时，只较弱煤柱侧基本顶不破断，最终断裂形态为非对称“U-X”型;④ 比值k/E或k/(Eh3)不变(k，E，h改变时，km1及km2与k保持某个任意比值不变)，基本顶破断规律不变。

The mechanical model of first fracturing of main roof considering the support of coal pillars and solid coal as elastic foundation on both sides of stope is established. Using the differential algorithm and the fracture criterion of pri- mary moment,it is found that ① when the elastic foundation coefficient k is smaller as well as the thickness of main roof h and the elastic modulus E is larger, the initial fracture position of main roof is the lower surface of central region of hanging roof area on weaker coal pillar side. On the contrary,the position is the upper surface of long side area a- head of solid coal on weaker coal pillar side. ② When the support coefficients km1 ,km2 and the widths L1 ,L2 of coal pil- lars on the two sides of stope change,the primary moments and their positions ahead of coal wall in the central area of main roof and solid coal area are almost unchanged. However,the values and the positions of primary moments of main roof in coal pillars area on the two sides of stope change significantly. ③ When the thickness h and elastic modulus E of main roof are larger and the values of L1 ,km1 ,L2 and km2 are smaller,the main roof in coal pillars area on the two sides of stope will not fracture. So the fracturing order of the roof is that the lower surface of central region of hanging roof area on weaker coal pillar side → the upper surface of long-side solid coal area on weaker coal pillar side,and the final fracture form is the type of asymmetric “ = -X”. On the contrary,the main roof in coal pillars area on the two sides of stope will fracture. Thus the fracturing order is that the upper surface of long-side solid coal area on weaker coal pillar side → the lower surface of central region of hanging roof area on weaker coal pillar side → the upper sur- face of coal pillar area on stronger coal pillar side → the upper surface of coal pillar area on weaker coal pillar side, and the final fracture form is the type of asymmetric “O-X”. However,when L1 ,km1 are smaller and L2 ,km2 are larger, only on weaker coal pillar side,the main roof will not fracture,and the final fracture form is the type of asymmetric “U- X”. ④ When k,E and h change as well as km1 and km2 keep a certain arbitrary ratio constant with k,the ratio k / E or k / (Eh3 ) is unchangeable and the fracture law of main roof is invariant.

XIE Shengrong,CHEN Dongdong,ZENG Junchao,et al. First fracturing characteristics of main roof plate structure con- sidering coal pillars and elastic coal foundation on both sides of stope[J]. Journal of China Coal Society,2019,44(1): 115-126.