摘要
为揭示多次开挖扰动下硬岩矿柱破裂失稳演化规律,以典型铁矿床为物理原型,运用VIC–3D非接触全场应变测量设备、应力与声发射监测系统,开展大尺度二维相似物理模拟试验。研究结果表明,矿柱在水平和垂直相邻矿房开挖过程中会发生多重叠加损伤,第一水平矿房间柱和中间矿房顶柱的损伤破坏严重,力学特性劣化程度高。在分析矿柱损伤、大变形、失稳垮塌等不同阶段演化特征的基础上,基于普氏压力拱理论,建立多水平矿房开挖矿柱失稳演化模型。矿房开挖初期矿柱处于低损伤阶段,属于稳定间歇期;随着矿柱损伤加重,导致矿柱失稳,顶板冒落,进入破坏突发期。矿柱损伤与失稳是引起空区垮塌的关键因素,应运用位移、声发射和应力等监测手段对损伤严重区域进行监测,在进入破坏期前采取有效的控制措施。
In order to reveal the crack and destabilization evolvement laws of hard rock pillars under dynamic excavation,taking typical iron deposit as physical prototype,the large scale model experiment was carried out using VIC–3D strain measurement equipment of non-contact and in-plane and stress monitoring system and acoustic emission.The results of research indicate that multiple superimposed damages will occur in pillars during excavation of adjacent stopes in horizontal and vertical directions,the barrier pillars and central top pillar of first layer are damaged seriously and show a higher degree of degradation of mechanical properties.On the basis of the analysis of evolution characteristics of pillar damage,large deformation,instability collapse at different stages and based on the compressive arch theory,the destabilization evolution mode of pillars failure was established.Pillars are in low damage stages during the early excavation,which belongs to stable intermittent period.The increase of pillar damages leads to instability falling of barrier and top pillar,which belongs to bursting period.Pillar damages and instability were key factors causing the collapse of goaf,so the displacement,acoustic emission and stress monitoring methods should be used to monitor the severely damaged area,and effective control measures should be taken before the failure period of the pillars.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2017年第A02期3713-3722,共10页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(51374087
51404086)
河北省自然科学基金资助项目(E2014209093)~~
关键词
岩石力学
矿柱
动态扰动
破裂失稳
演化特征
rock mechanics
pillars
dynamic disturbance
crack and destabilization
evolution characteristics
