长壁工作面老顶初次断裂步距及类型的研究

STUDY OF THE SPAN AND TYPES OF INITIAL FRACTURING OF MAIN ROOF IN LONGWALL FACE

本文根据采场老顶所处的力学环境,建立起相应的力学模型,求解出老顶的弯矩修正系数,分析了老顶的弯矩分布规律。研究提出了老顶初次断裂存在着三种类型,建立了初次断裂步距及类型的计算方法。结果表明,老顶初次断裂步距应在反映自身稳定性的步距基数A基础上,用反映周围力学环境的刚度比β、载荷比D、载荷范围b_1进行修正。

According to the mechanical position of the maia roof,this paper builds up a corresponding mechanical model,gives out bending moment corre- ction coefficient of main roof and analyses bending moment distribution law. The paper also reveals that initial fraoturing of main roof has three types and develops the computing method of the span and types of initial fracturing of main roor.The result shows that initial fracturing span of main roof should be corrected by using stiffness ratic β、load ratio D and load range b_1 which reflect mechanical position of main roof on the basis of span cardinal number A which reflects the stableness of main roof itself.