摘要
采用理论分析和数值模拟的方法,以陕北煤田韩家湾矿近距离煤层2-2煤和3-1煤为研究对象,对煤柱的应力分布及传递规律进行研究。结合煤层具体赋存条件计算煤柱的塑性区宽度,分析韩家湾矿残留煤柱支撑能力。对4种尺寸的煤柱应力在底板中的分布规律进行力学分析,得到不同尺寸煤柱在底板各深度的应力曲线。运用FLAC 3D软件对韩家湾煤矿2-2煤房柱区留设的4种尺寸的间隔煤柱应力分布进行模拟,得出不同尺寸煤柱应力在底板岩层中的分布图。结果表明:残留煤柱承载着上覆岩层的重量,沿煤柱中心线向下传递到底板岩层中,呈半椭圆型分布,在煤柱下方形成应力增高区,应力以中心线为轴向两侧形成对称分布;煤柱应力在底板岩层中的传递与煤柱的尺寸大小有关,煤柱尺寸越大,应力在底板岩层中向下传递的越远、分布范围越广;下煤层开采进入14 m煤柱下方边界时,受双重应力作用,易引起顶板整体切落,对工作面造成的安全隐患较大。
Taking close distance coal seams in 2-2 coal and 3-1 coal in Hanjiawan coal mine of Shanbei coalfield as the research object,the stress distribution and transfer rule of coal pillar were studied by means of theoretical analysis and numerical simulation.The plastic zone width of coal pillar is calculated according to the specific conditions of coal seam occurrence,and the supporting capacity of remaining coal pillar in Hanjiawan mine is analyzed.The stress distribution of four sizes of coal pillar in the floor is examined,and the stress curves of coal pillar with different sizes in different depths of the floor are obtained.FLAC 3D software was used to simulate the stress transfer of spaced coal pillars of four sizes in the 2-2 coal room and pillar area of Hanjiawan coal mine,the stress distribution maps of coal pillars of different sizes in the floor strata are obtained.The results show that the weight of overlying strata which is distributed in a semi-ellipse shape along the central line of the coal pillar to the floor strata is carried by the residual coal pillar.The stress-concentrated area is formed under the coal pillar and the stress which takes the center line as the axis forms a symmetric distribution on both sides.The stress transfer of coal pillar in floor rock stratum is related to the size of coal pillar.The larger the coal pillar is,the farther the stress is transferred downward in the floor rock stratum and the wider the distribution range is.When the mining of the lower coal seam enters the lower boundary of the 14 m interval coal pillar,it is easy to trigger the whole roof cutting off under the influence of double stress,which causes a great hidden danger to the working face.
作者
齐学元
邓广哲
黄康
QI Xueyuan;DENG Guangzhe;HUANG Kang(College of Energy Science and Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;School of Mines,Inner Mongolia University of Technology,Hohhot 010051,China;Key Laboratory of Western Mine Exploitation and Hazard Prevention,Ministry of Education,Xi’an University of Science and Technology,Xi’an 710054,China)
出处
《西安科技大学学报》
CAS
北大核心
2021年第4期649-656,共8页
Journal of Xi’an University of Science and Technology
基金
内蒙古工业大学科学研究项目(2016030092)
内蒙古自治区自然科学基金项目(2020MS04009)。
关键词
近距离煤层
残留煤柱
底板
应力传递
数值模拟
close distance coal seam
residual coal pillar
floor
stress transfer
numerical simulation
