真三轴卸载-动力扰动下含裂隙砂岩破坏特性研究  

Investigation on the failure characteristics of fissured sandstone under true triaxial unloading and dynamic disturbance condition

作　　者：冯帆[1] 谢志伟 陈绍杰[1] 赵兴东[2] 闫至开 石建龙 FENG Fan;XIE Zhiwei;CHEN Shaojie;ZHAO Xingdong;YAN Zhikai;SHI Jianlong(School of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao,Shandong 266590,China;School of Resources and Civil Engineering,Northeastern University,Shenyang,Liaoning 110819,China)

机构地区：[1]山东科技大学能源与矿业工程学院,山东青岛266590 [2]东北大学资源与土木工程学院,辽宁沈阳110819

出　　处：《岩石力学与工程学报》2025年第3期618-637,共20页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(52374095,52004143,52130403)。

摘　　要：为探究深部含裂隙岩体在动静组合应力状态下的破坏特性,采用QKX-YB200真三轴岩爆试验系统、声发射监测系统以及摄像机对不同裂隙倾角θ、初始静应力σ_(s)及动力扰动条件(扰动方向、扰动幅值σ_(d)和扰动频率f)下红砂岩开展真三轴卸载-动力扰动试验。研究结果表明:(1)在真三轴卸载-动力扰动条件下,含裂隙砂岩的破坏模式均为张-剪混合型破坏,但不同影响因素下张拉和剪切裂纹的占比有所不同。(2)对于已发生失稳破坏的试样,裂隙尖端翼裂纹扩展由θ<90°时的单一顺翼裂纹或顺-反组合翼裂纹转变为θ=90°时的单一反翼裂纹。(3)含裂隙砂岩的分形维数和破坏剧烈程度均随着θ增加呈现出先减小后增加的趋势,和σ_(s)和σ_(d)呈正相关关系,但与f呈负相关关系;当动力扰动由最大主应力方向变为中间主应力方向时,砂岩未发生整体失稳破坏,也未形成岩爆。(4)建立真三轴卸载-动力扰动条件下含裂隙砂岩的翼裂纹扩展模型,并结合动力扰动时长与砂岩内部所处的应力环境对翼裂纹扩展机制进行初步探讨。(5)通过探究真三轴卸载-动力扰动下含裂隙试样的能量演化全过程,总结触发型岩爆发生的能量条件,并分析不同影响因素对于含裂隙砂岩岩爆灾害的定量贡献。该研究可为深部含裂隙采动硬岩的稳定性评估与灾害防控提供理论指导。In order to investigate the failure characteristics of fissured sandstone subjected to combined dynamic and static stress states,the true triaxial rockburst test system(QKX-YB200),acoustic emission monitoring system and camera were used to conduct true triaxial unloading and dynamic disturbance tests on red sandstone under different fissure inclinations θ,initial static stresses σ_(d) and dynamic disturbance conditions(disturbance directions,disturbance amplitudes σ_(s)and disturbance frequencies f).The results indicate that:(1)The failure mode of fissured sandstone is tensile with shear failure under true triaxial unloading and dynamic disturbance condition,while the proportion of tension cracks and shear cracks varies depending on different influencing factors.(2)For the specimens that have undergone instability failure,the wing crack propagation at the tips of the fissure transforms from single wing cracks or a combination of wing and anti-wing cracks at θ<90°to single anti-wing cracks at θ=90°.(3)The fractal dimension and the failure severity of the sandstone both exhibit a trend of first decreasing and then increasing with the increase in θ.Additionally,these properties are positively correlated with σ_(s)and σ_(d),but negatively correlated with f.When the dynamic disturbance shifts from the direction of the maximum principal stress to the direction of the intermediate principal stress,the overall instability failure of sandstone do not occur.(4)The wing crack propagation model of fissured sandstone under true triaxial unloading and dynamic disturbance condition was established.Additionally,the mechanism of wing crack propagation was investigated in relation to the duration of dynamic disturbance and the internal stress environment of sandstone.(5)By investigating the entire energy evolution process of fissured sandstone under true triaxial unloading and dynamic disturbance,the energy condition of triggering rockburst has been summarized.Additionally,the quantitative contributions of various influe

关 键 词：岩石力学 真三轴卸载-动力扰动 裂隙砂岩 扰动参数 破坏特性 岩爆特征 

分 类 号：TU45[建筑科学—岩土工程]