一种基于板结构理论的顶板初次垮断步距简便计算方法-岩土力学.PDF

第 31 卷 第 3 期 采矿与安全工程学报 Vol.31 No.3 2014 年 05 月 Journal of Mining Safety Engineering May 2014 文章编号：1673-3363-(2014)03-0399-071 一种基于板结构理论的顶板初次 垮断步距简便计算方法 吴锋锋，刘长友，杨敬轩 ( 中国矿业大学矿业工程学院，煤炭资源与安全开采国家重点实验室， 深部煤炭资源开采教育部重点实验室，江苏 徐州 221116) 摘要 为便于采用板的经典理论对岩层初次垮断进行分析，采用理论分析与现场实测相结合的方 法，探讨了连续线性载荷形式作用下，顶板简支与固支边界时的初次垮断步距计算方法。研究得 到，顶板破断危险点位置弯矩随顶板两向长度比值变化的关系，给出顶板两向长度任意比值条件 下的顶板最大弯矩表达式；得到了倾斜顶板梯形载荷作用下，简支与固支顶板的最大应力分布表 达式；提出了一种基于板结构理论的顶板初次垮断步距简便计算方法。通过对淮北矿区桃源煤矿 8281 工作面顶板初次破断的现场实测与理论分析对比，顶板初次垮断步距实测数据(25~34 m)与 理论计算结果(26.5~35.5 m)基本一致，表明该算法对顶板岩层初次垮断步距的预测具有良好的适 用性。 关键词 板理论；垮断步距；梯形载荷；顶板弯矩 中图分类号 TD 821 文献标志码 A A simple calculation method for roof first caving span based on the plate structure theory WU Fengfeng ，LIU Changyou ，YANG Jingxuan (School of Mines，State Key Laboratory of Coal Resources and Safe Mining，Key Laboratory of Deep Coal Resource Ming Ministry of Education，China University of Mining Technology，Xuzhou ，Jiangsu 221116 ，China) Abstract To analyze the roof first caving span based on the plate structure theory, considering the roof strata are loaded by continuous linear action, the roof first caving spans in the simply supported and clamped boundaries were investigated respectively by using the theoretical analysis and field measure- ment. In this paper, the relationship between the bending moment in the rupture peril point of roof and ratio of roof length in the two directions (strike and inclined directions) were obtained, and the largest bending moment expression under the random length ratio of the two d