摘要
首先对修建于我国西南地区雅砻江干流上重要的梯级电站——锦屏一级水电站地下厂房洞室群的巨大规模、布置的复杂性,以及在极高地应力作用,和受到3条大断层及多组节理切割等复杂地质条件下,由于岩体强度较低及工程地质条件的不利组合,对地下厂房洞室群的稳定性提出的严峻挑战进行介绍。对该地下厂房洞室群施工中出现的远远超过同等规模的其他地下厂房的围岩变形,并表现出明显的时效性,还有衬砌开裂、围岩松动区持续加深、已经施工的锚杆锚索张力超限以及突然释放等各种特殊现象进行描述;然后从高地应力特点、岩体流变特性、变形特性等角度对这些现象产生的原因进行初步分析;最后针对上述情况对渐进性支护施工、分级控制锚索初始锁定张力、松动圈强化固结等若干对策的可行性进行探讨。
A brief introduction is given to the great challenge in the construction of Jinping I hydropower station, which is a key cascade underground hydropower project, located in the Southwest China, at the Yalong River. The challenge is caused by the following features. The project is very huge and the underground powerhouse system is very complicated, as well as the very high geostress and the complex geological conditions, including 3 large-scale faults and multiple sets of joints existing in the surrounding rock mass with poor quality combination. A detailed description is carried out to the extremely large deformations which is far beyond the deformation of other underground powerhouses with the same range of scale, and the time-related features of the deformation, the severe cracks of linings, the damaged zones develop continually, the over-loading of the rock-bolts and anchorages, during the excavation of the underground powerhouse caverns. All these phenomena happen frequently. Then, a preliminary analysis of those particular situations is given from the point of view of the relation of high stress level and the rheological feature of the rock mass. Finally, the feasibilities of several countermeasures are discussed, such as gradual support method, hierarchical controlling to the initial pre-stress of anchors, damage-zone consolidation and strengthening by the combination of bolting and grouting.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2009年第11期2167-2175,共9页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金雅砻江水电开发联合研究基金重点项目(50539090)
国家自然科学基金资助项目(50779025)
关键词
水利工程
地下厂房
洞室群
极高地应力
时效性
稳定性
对策
hydraulic project
underground powerhouse
cavern groups
extreme-high geostress
time effect
stability
countermeasures
