摘要
为了探索深部巷道围岩锚固结构从开始承载至整体失稳全过程,揭示围岩内部应力及变形破裂演化规律,以口孜东矿-967 m水平西翼轨道大巷为工程背景,依托自主研制的深部地下工程结构失稳全过程模拟试验系统,结合声发射、电磁辐射、电阻率、数字散斑等多源地球物理信息监测技术,对无支护、锚杆支护及锚杆索支护巷道围岩锚固结构承载特性及变形破裂演化特征进行大尺度物理模型试验研究。试验获得了不同支护锚固结构变形破裂全过程荷载-位移曲线,随着支护强度的增加,荷载-位移曲线应力跌落现象逐渐减弱,而锚固结构峰值承载能力、等效弹性模量和峰值位移分别增加了82.57%,33.33%和107.24%,巷道围岩越容易形成“压力拱”结构效应,抵抗变形的能力逐渐增强;试验过程中,顶板围岩变形量最大,两帮次之,底板最小,锚固结构破坏特征随支护强度的增加由张拉裂纹为主的脆性破坏向剪切滑移为主的塑性破坏转化;多源地球物理信息响应特征与荷载-位移曲线具有良好的耦合关系,随着支护强度的增加,锚固结构内部单位时间破坏次数逐渐减少,电磁辐射强度及脉冲数均逐渐减弱;声发射事件与锚固结构裂纹萌生扩展呈现较好的对应特征,在模型进入非稳定破坏阶段,随着裂纹迅速扩展,声发射活动异常活跃;随着荷载的增加,锚固结构由于裂纹发育趋于松散破裂,视电阻率逐渐升高导致区域导电能力逐渐降低,随着支护强度的增加,锚固结构的高阻区形成时间变大而范围变小。
This paper aims to explore the whole process from initial load bearing to the overall instability of surrounding rock anchorage structure of the deep-buried roadway,and to reveal the evolution characteristics of the internal stress,deformation and fracture of the surrounding rock.Based on the engineering background of-967 m west wing track roadway of Kouzidong coal mine,various large-scale simulation experiments on the deformation,failure evolution characteristics,and the bearing capacity of roadway surrounding anchorage structure with no support,bolt support and bolt-cable anchor support were respectively carried out using the self-developed simulation testing system for the whole process of structural instability in deep underground engineering project.The load-displacement curves of the whole process of deformation and failure of the anchorage structures with different supporting forms were obtained through the test.With the increasing supporting strength,the stress drop phenomenon of the load-displacement curves gradually weakens,while the peak bearing capacity,equivalent elastic modulus,and peak displacement increase by 82.57%,33.33%,and 107.24%,respectively.It is easier for the surrounding rock to generate the structural effect of“pressure arch”,and the deformation resistance capacity gradually enhances.During the test,the deformation of the roof is the largest,followed by the two sides,and the floor is the smallest.As the support strength increases,the failure characteristics of the anchorage structure transforms from brittle failure dominated by tension cracks to plastic failure dominated by shear slip.The response characteristics of the multi-source geophysical information have a good coupling relation with the load-displacement curves.With the increase of supporting strength,the number of failure per unit time in the anchorage structure gradually decreases,and both the electromagnetic radiation intensity and number of pulses gradually weaken.The acoustic emission events exhibit a good corresponding feature with the crack initiation and development in the anchorage structures.When the model enters the unstable failure stage,with the rapid crack growth,the acoustic emission activity is very active.As the applied load increases,the anchorage structure tends to be loosely broken due to gradual crack development,resulting in gradual increase in the apparent resistivity while gradual decrease in the regional conductivity.With the increasing supporting strength,the formation time of high resistance zone in the anchorage structure becomes larger but the range becomes smaller.
作者
靖洪文
尹乾
朱栋
孙彦景
王勃
JING Hongwen;YIN Qian;ZHU Dong;SUN Yanjing;WANG Bo(State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology,Xuzhou 221116,China;School of Information and Control Engineering,China University of Mining and Technology,Xuzhou 221116,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2020年第3期889-901,共13页
Journal of China Coal Society
基金
国家自然科学基金资助项目(51734009)
国家重点研发计划资助项目(2017YFC0603001)
江苏省自然科学基金资助项目(BK20180663)。
关键词
深部巷道
锚固结构
变形破裂
承载特性
信息化
deep-buried roadway
anchorage structure
deformation fracture
bearing capacity
informationize