厚硬岩层周期破断步距计算及影响因素分析

Calculation of periodical fracture interval and analysis of influencing factors in thick and hard rock strata

针对众多地区采场覆岩存在厚硬岩层,破断岩块块度较大,导致破断步距计算公式结果失真的问题,考虑岩块间相互作用力及支护参数等多重因素,结合材料力学中的组合变形,建立了厚硬岩层周期破断步距力学模型,得出了周期破断步距计算公式,通过现场实测数据对所推导公式进行了实证,并与传统悬臂式破断步距计算公式进行对比。研究结果表明:随岩层厚度的增大,传统计算公式结果偏离实际值愈发明显,而推导的步距计算公式则可与实际较好吻合,具有较高的可靠性和合理性。

As the stope overburden in some districts has thick and hard rock formation,the blockness of broken rock mass is big,resulting in distortion of breaking span calculation formula.Considering various factors such as interaction of the rocks and the support parameters,using combined deformation in material mechanics,the thick and hard rock formation periodical fracture interval mechanical model is established,and the periodical fracture interval calculation formula is obtained,the derivation formula is proved by the on-site measurement data and compared with the traditional boom-type calculation formula.The research result shows that as the rock formation thickness increases,the result of traditional calculation formula increasingly deviates from the actual value,while the result of the derived formula coincides well with the actual value.