巴基斯坦某特大断面导流洞台阶开挖优化研究  

Study on Optimization of Bench Excavation for a Large Section Diversion Tunnel in Pakistan

作　　者：裴向辉[1] 彭小川[1] PEI Xiang-hui;PENG Xiao-chuan(Bei Fang Investigation,Design & Research CO.,LTD.,Tianjin 300222,China)

机构地区：[1]中水北方勘测设计研究有限责任公司,天津300222

出　　处：《云南水力发电》2023年第4期172-175,共4页Yunnan Water Power

摘　　要：导流洞开挖方案设计直接关系到导流洞的施工方法、施工速度及施工安全。以巴基斯坦某特大断面导流洞为例,通过数值模拟方法,对导流洞的台阶开挖方案进行对比分析。结果表明,在Ⅳ类围岩下,不同开挖方案下的收敛均能满足规范要求;将前两步开挖合并为一步时,隧道收敛性较分步开挖有所提高,增幅为4%;合并开挖后,塑性区较分步开挖塑性半径增大1%;锚杆最大内力最大降低了5.65%。合并方案成功应用于导流洞实际开挖支护中。The excavation scheme design of diversion tunnel is directly related to the construction method,construction speed and construction safety of diversion tunnel.Taking a large section diversion tunnel in Pakistan as an example,through numerical simulation method,this paper makes a comparative analysis on bench excavation scheme of the diversion tunnel.The results show that the convergence under different excavation schemes can meet the specifications under the IV surrounding rocks.When the first two excavations are combined into one step,the convergence of the tunnel is improved by 4%compared with that of step-by-step excavation.After combined excavation,the plastic radius of plastic zone increases by 1%compared with that of step-by-step excavation.Maximum internal force of anchor rod is reduced by 5.65%.The combined scheme has been successfully applied in the actual excavation and support of diversion tunnel.

关 键 词：导流洞 特大断面 台阶开挖 初次支护 收敛 

分 类 号：TV544.1[水利工程—水利水电工程]