大跨度复合顶板开切眼变形特征及控制技术  

Deformation Characteristics and Control Technology of Large Span Composite Roof Open-off Cut

作　　者：刘治成 朱磊 刘永强 LIU Zhicheng;ZHU Lei;LIU Yongqiang(China Coal Energy Research Institute,Co.,Ltd.,Xi'an 710054,China;Zhongtian Hechuang Energy Corporation Limited,Ordos 017399,China)

机构地区：[1]中煤能源研究院有限责任公司,陕西西安710054 [2]中天合创能源有限责任公司,内蒙古鄂尔多斯017399

出　　处：《煤矿安全》2020年第11期83-88,93,共7页Safety in Coal Mines

摘　　要：为了解决大跨度开切眼复合顶板破坏迅速、持续时间长、变形剧烈等控制难题,通过现场实测得到复合顶板结构特征,并利用FLAC3D软件统计分析了不同迭代次数下开切眼顶底板及帮部的位移变化情况和塑性区发育特点,揭示出单一顶板与复合顶板条件下开切眼围岩变形和塑性区发育的规律和变形特征;同时,基于Goodman弹性夹层理论建立了复合顶板弹性夹层组合梁力学模型,得到了复合顶板极限跨距的计算公式;最后,对"锚杆锚索+单体支柱"联合支护参数进行了优化。现场实践结果表明:在掌握大跨度复合顶板结构特点和破坏特征的基础上,以"强力锚杆锚索+单体支柱"为核心的支护方案中,开切眼顶板0~4.0 m的岩层离层平均值为108 mm,支护方案有效的控制了大跨度复合顶板开切眼围岩变形。In order to solve the control problems of open-off cut composite roof,such as rapid damage,long duration and severe deformation,the structural characteristics of composite roof are obtained through field measurement,and the displacement changes and plastic zone development characteristics of open-off cut floor and side under different iterations are statistically analyzed by FLAC3 D software,which reveals that the law of development and deformation characteristics of the plastic and plastic zone of the surrounding rock changes under the condition of single roof and composite roof.At the same time,based on Goodman’s elastic sandwich theory,the mechanical model of composite roof elastic sandwich composite beam is established,and the calculation formula of the limit span of composite roof is obtained.Finally,the parameters of"bolt cable+single pillar"combined support are optimized.The field practice results show that,on the basis of mastering the structural characteristics and failure characteristics of the large-span composite roof,in the support scheme with"strong anchor cable+single pillar"as the core,the average value of0-4.0 m rock separation layer is 108 mm,and the support scheme effectively controls the deformation of the surrounding rock in the opening of the large-span composite roof.

关 键 词：复合顶板 开切眼 顶板变形特征 顶板控制 数值模拟 

分 类 号：TD327.2[矿业工程—矿井建设]