摘要
为了探讨液压与气液复合加载条件下地下洞室岩爆现象的差异,选择具有明显脆弹性的石膏模型材料,制作了大尺寸模型试件,利用自主研发的气液复合型岩爆模型试验装置开展液压与气液复合加载洞室岩爆物理模型试验,模拟深部地下洞室开挖过程中的岩爆现象。采用应力应变测试、声发射监测及影像获取等方法,对试件加载过程中洞室的宏观破坏现象、洞室周边内部变形规律、声发射特征参数及裂纹的扩展进行分析。试验结果表明:洞室边墙和拱肩部位产生较大的应力集中区,洞室岩爆破坏顺序是先边墙,后拱肩方向,边墙和拱肩部位在极短的时间内出现裂纹及扩展,形成较大范围的层裂、剥落及弹射碎片,并伴随较大的声响;在相同的加载应力路径下,气液复合加载较液压加载破坏区范围更大,在本试验气液复合加载条件下,边墙破坏区范围大致为0.6b(b为洞室宽度);岩爆的发生及烈度与加载方法和破坏时能量的释放速率密切相关,采用气液复合加载的模型试件,在对应破坏点处应变具有明显的梯度变化,应变值显著高于液压加载试件,同时,声发射能量较液压加载具有明显的突变,岩爆的宏观破坏过程及现象更为明显,破坏程度更为剧烈。气液复合加载的试验方法更为符合实际工程岩体破坏过程的实际受荷。
In order to investigate the difference of rock burst phenomena in underground under hydraulic and gas-liquid compound loading conditions,selecting a gypsum model material with brittle elasticity,a large scaled model specimen is produced. Meanwhile,a self-designed gas-liquid compound loading test device is developed to conduct the cavern rock burst physical model test under hydraulic and gas-liquid loadings to simulate the rock burst phenomenon in the process of excavation in deep underground caverns. With the methods of stress-strain testing,acoustic emission monitoring and imaging retrieval,the macroscopic failure features,the interior deformation characteristics around the cavern,the acoustic emission characteristic parameters and the crack propagation in the loading process of specimen are analyzed. The test result shows that（1） Cavern wall and spandrels create a larger stress concentration zone,the rock burst of cavern appears in the side wall firstly then spandrel,the cavern wall and spandrels are cracked and expanded in a very short time,forming a wide range of cracks,spalling and ejection fragments,accompanied by a large sound.（2）The failure zone under the gas-liquid compound loading is larger than that under the hydraulic loading at the same stressing paths. The damage range of the cavern wall is 0. 6 b（ b is the cavern width） under the gas-liquid compound loading condition.（3） The occurrence and intensity of rock burst are closely related to the loading method and the energy release rate during the rock burst process. In the model specimen under the gas-liquid compound loading,the obviously gradient change appears at the corresponding failure point,the strain value is significantly higher than of the hydraulic loading specimen.（4） The acoustic emission energy has obvious mutation compared with the hydraulic loading. The macroscopic failure process and phenomena of the rock burst are more obvious,and the degree of rock burst is more severe. Therefore,the test method using gas-liquid co
作者
祝文化
燕星
刘畅
夏元友
ZHU Wen-hua;YAN Xing;LIU Chang;XIA Yuan-you(School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan Hubei 430070, Chin)
出处
《公路交通科技》
CAS
CSCD
北大核心
2018年第7期86-92,135,共8页
Journal of Highway and Transportation Research and Development
基金
高等学校博士学科点专项科研基金项目(20110143110017)
中央高校基本科研业务费专项资金项目(2014-IV-150)
关键词
隧道工程
岩爆
模型试验
洞室
三向应力
气液复合
大尺寸试件
tunnel engineering
rock burst
model test
cavern
3D stress
gas-liquid compound h）ading
large-scaled specimen
