| 四川康定某深埋隧道花岗岩岩爆物理模拟实验研究 |
| |
| 引用本文： | 严孝海,郭长宝,刘造保,王炀,刘冬桥,刘贵.四川康定某深埋隧道花岗岩岩爆物理模拟实验研究[J].地球科学,2022,47(6):2081-2093. |
| |
| 作者姓名： | 严孝海 郭长宝 刘造保 王炀 刘冬桥 刘贵 |
| |
| 作者单位： | 1.东北大学资源与土木工程学院, 深部金属矿山安全开采教育部重点实验室, 辽宁沈阳 110819 |
| |
| 基金项目： | 中国地质调查局项目(No.DD20190319)； |
| |
| 摘 要： | 四川康定折多山某隧道因其埋深大、构造应力高度集中，在修建过程中极易产生岩爆.为探索折多山某隧道花岗岩段不同深度条件下岩爆机制，利用真三轴岩爆实验系统，开展了不同深度下的花岗岩岩爆物理模拟实验.借助应力监测、高速摄像和声发射等系统，从声、光、力等多角度研究了折多山某隧道花岗岩岩爆的阶段特征、时间特征、主要破坏方式、裂纹演化等规律.结果表明:折多山花岗岩岩爆具有时滞性特征(time delaying rockburst，TDR)，在500~1 100 m不同埋深条件下，约770 m为折多山花岗岩单面临空真三轴强度的临界深度；不同深度下的岩爆有明显阶段特征，可分为平静期、劈裂成板、板折剥落、整体弹射4个阶段；声发射特征揭示折多山花岗岩岩爆主要为张拉破坏，随深度增加，张拉裂纹逐渐增加，剪切裂纹逐渐减少；根据岩爆时应力差与单轴抗压强度比值将折多山花岗岩岩爆分为3种破坏模式:小颗粒弹射破坏、岩板劈裂破坏、岩屑混合弹射破坏；且应力比值$ \left({\sigma }_{v}-{\sigma }_{h1}\right)/{\sigma }_{c} $越大，岩爆烈度越大.
|
| 关 键 词： | 深埋隧道 高地应力 岩爆 真三轴 声发射 岩土工程 |
| 收稿时间： | 2021-08-02 |
Physical Simulation Experiment of Granite Rockburst in a Deep-Buried Tunnel in Kangding County,Sichuan Province,China |
| |
| Abstract: | The deep-buried tunnel planned in Zheduo Mountain, Kangding County, Sichuan Province, is likely to rockburst due to its large buried depth and concentrated tectonic stress. In order to figure out the rockburst failure mechanism under different depths, in this study, the triaxial rockburst physical experiments of the granite in the Zheduo Mountain tunnel at different depths were carried out employing the stress monitoring system, high-speed camera system, and acoustic emission monitoring system. The phase characteristics, time characteristics, failure modes, and crack evolution of the granite in the Zheduo Mountain tunnel at different depths were studied with regard to the sound, light, and force and the experimental results show that the rockburst of Zheduo Mountain granite has obvious characteristics of time delaying rockburst (TDR). 770 m is the critical depth of the granite triaxial strength with one free face, and the lag characteristics of the excavation rockburst around this depth is obviously weakened. Rockburst at different depths can be divided into different stages: quiet period, splitting into plate stage, plate folding and spalling stage, and overall ejection stage. Rockburst acoustic emission characteristics reveal that the rockburst of Zheduo Mountain granite is mainly tensile failure, and with the increase of the depth, the number of tension cracks gradually increases and the number of shear cracks gradually decreases. According to the ratio of the stress difference and the uniaxial compressive strength at the time of the rockburst, the rockburst of Zheduo Mountain granite is divided into three failure modes: small particle ejection failure, rock slab splitting failure and mixed ejection failure, and the greater the stress ratio (σv-σh1)/σc is, the greater the rockburst intensity is. |
| |
| Keywords: | |
|
| 点击此处可从《地球科学》浏览原始摘要信息 |
|
点击此处可从《地球科学》下载全文 |
|
