针对神东矿区近距离采空区下工作面初采期间多次强烈矿压显现现象,采用现场实测、理论分析对初采期间不同区域矿压显现特征及其机理进行了分析.研究表明,相对于上位煤层常规工作面,下位煤层工作面矿压呈现明显的非周期性和分区演化特征,且采空下工作面初采期间来压位置与上覆单侧采空煤柱和关键层初次断裂位置相吻合,据此对初采期间矿压显现进行了分区.建立了工作面初采期间矿压显现各分区覆岩运动结构及其力学模型,分析了不同区域内矿压显现机理;工作面出上覆单侧采空煤柱阶段矿压显现受关键层破断与煤层间岩层的耦合作用,受层间距影响,工作面出现“偏态”矿压现象;工作面在采空区下回采时,由于煤层间岩层已破坏,其对来压期间矿压显现影响较小,对非来压期间矿压显现影响较大.提出了近距离采空区下工作面矿压防治措施,即在单侧采空煤柱下合理选择开切眼位置和合理提高工作面推进速度.%According to severe strata behaviors occur frequently during the primary mining of the panels under contiguous goaf,In Shendong mining area and it is urgent to know about its reasons.the strata behavior characteristics and its mechanism in different regions during the primary mining are analyzed based on field test and relevent theories.The results show that compared with conventional panels in the upper coal seam,strata behavior of the lower coal seam has obvious aperiodicity and zoning characteristics.Moreover,the weighting positions during the primary of the panel in close-distance goaf coincide with the top coal pillar and the first fracture position of the overlying key strata,and then based on that,the strata behaviors during primary mining are zoning.Strata movement structure and mechanical models in different strata behavior regions during the primary mining are established and the mechanisms of those regions are analyzed.For the region passing the overlying one-side mining pillar,the strata behavior is under the coupling effect of the breaking of key strata and the distance between coal seams,and it is the distance that leads to the eccentric strata behaviors along the panel.For the rest regions under the overlying goaf,the broken coal and rock mass has little influence on the strata behaviors during the weighting,but has a great influence on that of non weighting period.Some effective control measures are given finally.choosing the open-off cut position and increasing the advancingspeed reasonably.
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