摘要
针对倾斜节理岩体巷道锚固支护问题,为获得较好的锚固支护效果,以长城六矿1301工作面运输巷为工程背景,基于相似模拟试验和数值模拟分析,揭示了不同锚固角度倾斜节理岩体剪切破坏特征。研究结果表明:随着法向荷载的增加,锚固倾斜节理岩体峰值强度逐渐增加;法向荷载为4 MPa时,随着锚固角度的增大,倾斜节理岩体的峰值抗剪强度和残余强度均呈先上升后下降的趋势,并在锚固角度为45°时均达到最大值;随着锚固角度的减小,锚杆两侧的压力链逐渐增加,并在锚杆内部产生拉力链,即随着锚固角度的减小,锚杆逐渐起到轴向拉伸抑滑的作用,倾斜节理岩体的锚固效果逐渐提升,当锚固角度为45°时抑滑效果较优。根据位移演化规律分析获得,在锚固角度较大时,大部分锚杆未起到抗剪作用,限制锚杆周围区域颗粒位移的能力较差,锚固效果不显著;在锚固角度较小时,限制锚杆周围区域颗粒位移的能力较强,锚固效果较好。根据倾斜节理岩体锚固支护剪切破坏特征,分析获得岩体抗剪强度演化规律、裂隙扩展规律、岩体内部位移演化规律以及岩体内部接触力及应力张量演化规律,综合确定当锚固角度为45°时倾斜节理岩体表现出较优的锚固支护效果。
To obtain better anchoring effect of anchoring support in inclined jointed rock mass roadway,taking the transportation roadway in 1301 working face of Great Wall No.6 Mine as the engineering background,the shear failure characteristics of inclined jointed rock mass with different anchoring angles are revealed based on similar simulation test and numerical simulation analysis.The results show that with the increase of normal load,the peak strength of anchorage body increases gradually.Under the normal load of 4 MPa,the peak shear strength and residual strength both increased first and then decreased with the increase of anchorage angle,and reached the maximum at 45°.With the decrease of anchorage angle,the pressure chains on both sides of the anchor gradually increase,and tension chains are gradually generated inside the anchor.In other words,with the decrease of anchorage angle,the anchor gradually plays the role of axial stretching and sliding suppression,and the anchoring effect of jointed rock mass gradually improves,and the sliding suppression effect is better when the anchorage angle is 45°.Based on the analysis of displacement evolution law,it is concluded that when the anchoring angle is large,most anchors do not play a shearing role,and the ability to constraining particle displacement around the anchor is poor,and the anchoring effect is not obvious.While the anchoring angle is small,the ability to limit particle displacement around the anchor is strong and the anchoring effect is good.On the basis of analysis,the evolution laws of shear strength,crack propagation and internal displacement of jointed rock mass,as well as the evolution laws of internal contact force and stress tensor of jointed rock mass are obtained.Better anchoring support effect is observed when the anchoring angle is 45°.
作者
李青海
柳昌涛
史卫平
石利伟
杨涛
LI Qinghai;LIU Changtao;SHI Weiping;SHI Liwei;YANG Tao(College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China;College of Civil Engineering and Architecture,Shandong University of Science and Technology,Qingdao 266590,China;Otok Front Banner Great Wall No.6 Mining Co.,Ltd.,Ordos 017000,China)
出处
《采矿与岩层控制工程学报》
北大核心
2023年第4期1-12,共12页
Journal of Mining and Strata Control Engineering
基金
山东省自然科学基金重点资助项目(ZR2020KE030)
国家自然科学基金资助项目(52274218)。
关键词
倾斜节理
锚固角度
抗剪强度
破坏特征
裂隙扩展
inclined joint
anchorage angle
shear strength
failure characteristics
crack propagation
