摘要
为深入研究深埋硬岩隧洞在落底开挖前后的围岩损伤破坏情况,结合锦屏二级水电站引水隧洞实际资料,借助RFPA有限元数值分析软件,研究岩体微破裂萌生、发育和扩展的演化机制。分析表明,在落底开挖过程中,由于开挖卸载,形成二次分布的应力场,在高应力和材料物性劣化的共同作用下,落底前的损伤会进一步发展,进而迫使局部应力场不断调整,诱发损伤向深处演化,同时引发已支护部分围岩出现损伤破坏。研究成果为更好地理解高应力下深埋硬岩隧洞的围岩损伤破坏模式提供重要参考。
The damage features of surrounding rock in the process of bottom excavation in deep hard rock tunnel are investigated, combining with the actual tunnel data of Jinping Ⅱ Hydropower Station and using numerical simula- tion approach RFPA. A study on the evolution mechanism of microfractures initiation, growth and expansion in deep intact rock mass is performed. It ＇ s shown that under the joint action of high stress and deterioration of the material, the damage position of bottom falling developed to deeper surrounding rock from the initial damage position caused by stress field adjustment, and the zone that had been supported also had some damage. The research results provide important references to understand the damage features of surrounding rock in deep hard rock under high geostress.
出处
《地下空间与工程学报》
CSCD
北大核心
2014年第1期36-42,共7页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金委创新研究群体基金(51121005)
国家自然科学基金(50909013)
国家重点基础研究发展计划(973)(2011CB013500)
关键词
深埋硬岩
落底
围岩损伤
数值分析
deep hard rock
bottom excavation
damage of surrounding rock
numerical analysis
