综放开采上位岩层的平衡结构及其对采场矿压显现的影响

The balance structure of main roof and its action to top coal in longwall top coal caving workface

在实测资料、模拟实验及工作面矿压显现特征的基础上,对综放工作面矿压显现内在机理及上覆岩体的平衡结构进行了分析研究.综放工作面上覆岩层存在着比分层开采层位更高的平衡结构,以大变形梁的形式存在.结构的活动是一逐渐变化的过程,在这一过程中,平衡结构与其下的顶板及顶煤相互作用,这种作用方式与顶煤的多次损伤有关.根据顶煤的损伤因子D、顶煤应变ε可以确定出合理的支护阻力,而ε可由大变形梁的位移及顶板的变形推出.

Based on the site measure data and the showing characteristics of ground pressure around Longwall Top Coal Caving(LTCC) workface, the paper proceeds analysis and research for the internal mechanism of the pressure showing and the structure of the main roof. There is a balance structure of upper rock layer in higher level compared with the layered extraction, which exists in the form of finite deformation beam. The activity of the structure is a process, in which the balance structure and the top coal interact, and the activity way relates to the multidamage of top coal. The reasonable support capacity can be calculated with the damage factor D and the strain ε of top coal, and ε can be obtained with the deformation of the finite deformation beam and the deformation of roof.