摘要
为探讨洞室围岩的破坏过程和机制,进行拉断裂和远场断裂破坏、V型坑破坏及分区破裂化3种破坏形式的试验研究。试验中采用平面和空间加载方式对预制洞室模型进行加载,通过白光散斑数字相关方法和声发射对模型洞室围岩的破坏过程进行监测,进而对3种破坏形式的形成机制进行分析。拉断裂和远场断裂破坏试验表明:远场断裂产生的力学机制主要是以拉应变集中,即拉断裂为主,拉压联合作用的结果;V型坑破坏试验表明:洞室围岩从局部破坏发展形成V型断裂区,后续断裂从V型断裂区尖端形成,向洞室围岩深部扩展;分区破裂化试验表明:洞室围岩深部的环向断裂是从洞室边界的局部破坏区尖端开始,向洞室围岩深部扩展,并在洞室边界与围岩深部环向断裂之间形成完整的没有破坏的区域。
To explore the fracture process and mechanism of underground caverns, three types of fractures which include primary and remote fracture, V-shape notches and zonal disintegration, have been studied by model experiments. The prefabrication cavern models were loaded under biaxial compressive loading and triaxial compressive loading. The fracture extension of the surrounding rock of model caverns are monitored by the white light digital speckle correlation method and acoustic emission. Based on laboratory test results, three types of fracture mechanisms were analyzed. The experimental results of primary and remote fracture show that the remote-fracture mechanical mechanism is the tensile strain concentration, and the tensile strain is the main focus and the combined effect of tension and compression. The experimental results of V-shape notches show the surrounding rock fractures of underground caverns form in the local area of the border of the model caverns, then extend to form the V-shaped fracture zones. The follow-up fracture in the tip of V-shape notches of model caverns expands to the surrounding rock of model caverns. The experimental results of zonal disintegration show the circular fracture of the deep surrounding rock of model caverns forms in the tip of the local fracture area of the border of model caverns, and extend to the deep surrounding rock. At the same time, a non-fracture zone has formed intermediately in the border of underground caverns and the circular fracture of surrounding rock.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2010年第A01期2741-2745,共5页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学重大基金资助项目(50490275)
关键词
岩石力学:深部岩体
模型试验
分区破裂
V型断裂区
rock mechanics
deep rock mass
model experimental
zonal disintegration V-shape notch
