采空区下方近距离巷道加固设计及应用

摘要

Accordingtothestabilityof5705closeroadwaybelowNo.7coalseammined-outareainJinhua-gongmine,analyzesthereasonofwhichbolt,anchorcablesupportingeffectispoorontheroadway.Byusing FLAC3Dsoftwaresimulatethedeformationanddestructionoftheroadwayunderoriginalsupportprogram,theclose coalseamroofoccurredseriousdamageundertheinfluenceoftwomining,makesboltingandanchorcablesupporting lackofstablerockformationscanbeusedtoanchor,doublecolumnsteelbeamsreinforcementmethodachievedstress transferbetweentheroofandfloor,theroofweightandoverburdenstresstransfertothefloor,controltheirheaving floor.Throughcounter-forceoffloorheaveresistingtheroofrocksinking,makeseachotherdestructivepowercon-vertedaneffectivesupportingforce.Fieldtestshowsthatafterdoublecolumnsteelbeamsmethodreinforce5705road-way,theroofsinking,floorheaveandconvergencebetweentwosidesrespectivelyis28.0mm,53.6mmand55.0 mm,thesupporteffectsaregood.%　　针对晋华宫矿7＃煤层采空区下方5705近距离巷道的稳定问题，分析了锚杆、锚索支护对上述巷道支护效果较差的原因，利用 FLAC3D软件模拟了原支护方案下巷道的变形破坏情况，近距离煤层顶板在两次采动的影响下发生严重的破坏，使锚杆、锚索支护缺少可以用来锚固的稳定岩层；“双柱钢梁”加固法实现了顶底板间的应力传递，将顶板的自重及上覆应力传递到底板，以控制其底鼓，通过底板底鼓的反力抵抗顶板岩体的下沉，使彼此的破坏力转化为有效的支护力。现场实测表明，“双柱钢梁”法加固5705巷后，顶板下沉量、底鼓量和两帮移近量分别为28．0mm、53．6mm和55．0mm，效果良好。