含弱面岩石滑移破坏及锚固控制试验研究

Study on slip failure of rock with weak plane and anchorage control mechanism

为揭示矿山巷道破裂围岩锚固支护作用机理,对含不同角度(30°,45°,60°)弱面的节理岩石试件进行了单轴压缩试验,分析了加锚前后节理岩石破坏形态和强度特征,并采用数字散斑相关方法,研究了加载全过程变形场演化规律及锚固控制机制。研究结果表明:1)节理岩石失稳以弱面滑移为主,加锚后由连续滑动转变为间断式错动,其基体易产生压剪破坏;2)加锚提高了节理岩石峰值强度、弹性模量及极限应变量,且随弱面倾角增大(30°~60°),峰值强度呈下降趋势,而弹性模量呈上升趋势;3)根据节理岩石变形演化的弱面端部破裂、滑移面扩展、滑移变形3个阶段,锚杆支护机制可对应表现为变形协同作用、增韧抑裂作用和阻滑作用。

In order to reveal the bolt support mechanism of broken surrounding rock, uniaxial com-pression tests of joint rock specimens with different interfacial angles are experimented. The failure modes and strength characteristics of the anchored joint rocks and the no-anchored are analyzed. The evolution law of deformation field and the anchorage control mechanism are also researched by using the DSCM method. The results show： 1） The general failure mode of joint rock is the slip of weak plane for the anchorage rock which could present the compress-shear failure and that could turn into disconti-nue dislocation; 2） The anchorage increases the peak strength, elastic modulus and ultimate strain of joint rock and the peak strength decreases with the increase of interfacial angle, but the elastic modulus shows a rising trend; 3） According to the deformation evolution laws of joint rock, it has three stages：failure in the terminal part of weak plane, extension of slip plane and slip deformation. Meanwhile, the bolt support mechanism has three corresponding parts： deformation coordination, toughness strength and crack control and slip prevention.