采动裂隙分布及其演化特征的采厚效应  

Caving thickness effects on distribution and evolution characteristics of mining induced fracture

作　　者：杨科[1] 谢广祥[1] 

机构地区：[1]安徽理工大学煤矿安全高效开采教育部重点实验室,安徽淮南232001

出　　处：《煤炭学报》2008年第10期1092-1096,共5页Journal of China Coal Society

基　　金：国家重点基础研究发展计划(973)基金资助项目(2005cb221503);国家自然科学基金资助项目(50674003);安徽省优秀青年基金资助项目(08040106839)

摘　　要：基于长壁工作面非对称布置特点,以谢桥矿1151(3)综放工作面地质和开采条件为背景,采用实验室相似材料模拟、计算机数值模拟及理论分析综合方法,研究不同采厚采动裂隙分布及其演化的特征.研究表明,不同采厚覆岩垮落角变化不大,随工作面推进覆岩采动裂隙表现为"∩"型高帽状、前低后高驼峰状、前后基本持平驼峰状、前高后低的驼峰状4阶段演化特征,采动裂隙发育高度呈梯级跃升并逐渐趋于稳定,工作面围岩采动裂隙发育具有非对称性,工作面上部塑性区范围大于工作面中、下部;采动裂隙发育高度、工作面前方塑性区宽度、走向工作面后方围岩塑性区边界与采空区方向的夹角和倾向下山方向围岩塑性区边界与煤层夹角与一次采厚呈非线性正比,采动裂隙发育高度与一次采厚的比值和走向工作面前方围岩塑性区边界与推进方向的夹角与一次采厚成非线性反比,整体揭示了一次采厚变化对采动裂隙分布及其演化特征影响的采厚效应.In order to explore the influence of mining thickness on the mining induced fracture （MIF） distribution and evolution characteristics of rock surrounding the fully mechanized top-coal caving face, based on the unsymmetrical disposal longwall face, the analyses of material and numerical simulation were synthetically applied according to the geological and technical conditions of the No. 1151 （3） working face in Xieqiao Mine. The results show that with different mining thicknesses, the fractured angles of overlying strata are basically equable and the e- volution characteristics of overlying strata MIF are four phases includes the similar ＂ N＂ configuration, the frontagelow and rear-high hump configuration, the accordant hump configuration and the frontage-high and rear-low hump configuration, and the MIF heights are gradually step-increase during caving. And the MIF of rock surrounding faces is unsymmetrical and the plastic extent of top face is more extensive than the middle and bottom face. With the once mining thickness increase, the development height of MIF, the plastic extent width of face frontage, the angle between the plastic boundary line of face frontage and the caving orientation on the strike and the angle be-tween the plastic boundary line of face dip and coal seam to the dip are nonlinear direct ratio to once mining thick- ness, but the ratio of MIF height and once mining thickness and the angle between the plastic boundary line of face rear and the goaf orientation on the strike are nonlinear inverse ratio to once mining thickness. The mining thickness effects on the distribution and evolution characteristics of MIF were obtained.

关 键 词：采动裂隙 演化特征 采厚效应 综放开采 非对称布置 

分 类 号：TD823.97[矿业工程—煤矿开采]