岩腔深度对危岩失稳机制的影响分析

Analysis on influence of rock cavity depth on destabilization mechanism of perilous rock

为研究岩腔深度对危岩体失稳机制的影响,采用3D打印技术制备4种危岩理想概化模型,开展冰冻试验,结合数字图像相关(digital image correlation,DIC)方法对危岩破坏全程进行非接触式、实时变形观测。基于DIC计算得到的全场变形数据,从精细化角度定量分析主控节理面相对位移演化规律和危岩失稳破坏机制。研究结果表明:岩腔型危岩失稳机制与岩腔深度密切相关,当岩腔深度小于危岩体宽度时,危岩体表现为旋转张拉破坏;当岩腔深度等于危岩体宽度时,危岩体表现为拉剪破坏。此外,危岩体失稳时间具有随岩腔深度的增加而缩短的规律。研究结果可为量化揭示危岩体失稳机制提供1种新的思路。

To study the influence of rock cavity depth on the destabilization mechanism of perilous rock mass,four ideal generalized models of perilous rock were prepared by 3D printing technology.The freezing experiment was carried out,and the noncontact,real-time deformation observation was performed for the whole process of perilous rock failure in combination with the digital image correlation(DIC)method.Based on the full-field deformation data calculated by DIC,the relative displacement evolution of the main control joint surface and the destabilization failure mechanism of perilous rock were quantitatively analyzed from the fine-view perspective.The results show that the destabilization mechanism of the rock cavity type perilous rock is closely related to the rock cavity depth.When the rock cavity depth is less than the width of perilous rock,the perilous rock exhibits the rotational tensioning failure.When the rock cavity depth is equal to the width of perilous rock,the perilous rock exhibits the tensile and shear failure.In addition,the destabilization time of perilous rock mass is shortened with the increase of rock cavity depth.The research results can provide a new idea for quantitatively revealing the destabilization mechanism of perilous rock mass.