中文摘要：

为了改进采空区顶板管理方式,必须掌握顶板断裂的滞后性。顶板断裂的滞后性是顶板岩层蠕变损伤的结果。基于Kachanov蠕变损伤理论对采空区顶板的蠕变损伤过程进行了解析分析。采空区顶板的蠕变损伤断裂经历断裂孕育和裂隙扩展两个阶段。断裂孕育时间随材料的蠕变指数、上覆岩层压力的增大而减小;裂隙扩展时间也随材料的蠕变指数、上覆岩层压力的增大而减小,但随岩石的抗拉强度增大而增加。

英文摘要：

To improve the roof control in coal mining,this study investigates the delay property of roof fracture.The fracture delay is the result of roof rock creep damage.The process of roof creep damage is analyzed based on Kachanov creep damage theory.This process consists of two stages including fracture pregnant stage and crack extension stage.The fracture pregnant time decreases with the increase of material creep index and the loading of overlying strata rock.Also,the crack extension time decreases with the increase of material creep index and the loading of overlying strata rock while it increases with the increase of tensile strength of roof rock.