锦屏二级水电站深埋引水隧洞群允许最小间距研究  

Study on acceptable minimum interval of long deeply burial hydropower tunnels in Jinping II hydropower station

作　　者：江权[1] 冯夏庭[1] 周辉[1] 

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,武汉430071

出　　处：《岩土力学》2008年第3期656-662,共7页Rock and Soil Mechanics

基　　金：国家自然科学基金委员会;二滩水电开发有限责任公司雅砻江水电开发联合研究基金项目(No.50539090);中国科学院知识创新工程重要方向项目(No.KZCX2-YW-109-3);国家科技支撑计划项目(No.2006BAB04A06);国家自然科学基金资助项目(No.50579070)

摘　　要：锦屏二级水电站引水隧洞群最大的特点是埋藏深、地应力高、外水压力大。这一极端复杂的赋存环境给4条引水隧洞的中心线间距确定带来了很大的挑战。为此,首先通过流-固耦合的数值计算方法,对洞间岩体塑性区贯通与否、隧洞壁面关键点位移曲线拐点、收敛位移是否超出相关规范共3种判别标准进行分析后,得到引水隧洞群最小理论间距值为50m。进而在类比与引水隧洞本身相邻的辅助洞和国内外几个典型深埋隧洞的洞径、埋深和间距的基础上,综合确定深埋引水隧洞群的最小允许中心线间距为52m,为当前设计采用60m洞间距提供了有力的理论支持。The four hydropower tunnels of Jinping Ⅱ Hydropower Station are mostly over burden of 2000 m, surrounded by more than 44.2MPa high initial stress and 10MPa pore water pressure. It is a great challenge for designers to determine the acceptable minimum interval under extremely complex geological conditions. So a integrated criterion for determining acceptable minimum interval is proposed according to （1） the plastic zone connecting or not; （2） the inflexion of displacement curve of key points in tunnel （3） convergence displacement not exceeding the state specification. With above guidelines, the theoretical minimum interval of tunnel of 50 m is obtained, by hydro-mechanics coupling numerical simulation. At last, the modified result of 52 m is recommended for the acceptable minimum interval according to engineering analogy analysis of several typical deep tunnels. The conclusion shows that the design interval of 60 m at present is reasonable.

关 键 词：锦屏级二水电站 引水隧洞 最小允许间距 塑性区贯通 位移拐点 收敛位移 

分 类 号：TU451[建筑科学—岩土工程]