工程地质学报2016，Vol.24Issue(5)：775-787,13.DOI:10.13544/j.cnki.jeg.2016.05.007
高地应力条件下锦屏一级主厂房围岩松弛深度形成规律和支护时机研究
RELAXATION DEPTH AND SUPPORTING TIME OF UNDERGROUND POWER HOUSE SURROUNDING ROCK UNDER HIGH GEOSTRESS AT JINPING I HYDROPOWER STATION
摘要
Abstract
In recent years,some large and extra large hydropower projects have been built or are under construction in China.Underground caverns of these hydropower projects usually have problems of complex geological conditions and high geostress.High geostress often leads to failure of different degrees and relaxation of extraordinary depth in surrounding rock during the construction of caverns.In this paper,the development of relaxation in surrounding rock is studied through analyzing geophysical prospecting data while excavating of main powerhouse at Jinping I hydropower station.Optimal supporting time is studied through analyzing displacement and plastic zone of the surrounding rock through numerical analysis.It is shown that the plant axis should be parallel with the maximum principal stress,which can effectively reduce relaxation depth caused by the time-dependent deformation.80% of the relaxation depth in surrounding rock is formed after the excavation interval of 2 to 3 layers. Compared with the backward support,the displacement and plastic zone are obviously smaller when immediate support is applied.So,immediate support is beneficial to the stability of the surrounding rock.These research results can be used for reference when selection of plant axis,support design and supporting time determination of large underground caverns under high ground stress.关键词
锦屏一级水电站/高地应力/地下洞室/松弛深度/支护时机Key words
Jinping Ⅰ hydropower station/High geostress/Underground caverns/Relaxation depth/Supporting time分类
天文与地球科学引用本文复制引用
杨静熙,刘忠绪,黄书岭..高地应力条件下锦屏一级主厂房围岩松弛深度形成规律和支护时机研究[J].工程地质学报,2016,24(5):775-787,13.基金项目
国家自然科学基金项目（51379022，51539002）资助． （）
