涔天河工程1号泄洪洞出口边坡与隧洞联合变形分析  

COMBINED SLOPE AND TUNNEL DEFORMATION ANALYSIS FOR NO. 1SPILLWAY TUNNEL OUTLET OF CENTIANHE PROJECT

作　　者：李毅[1,2] 胡兰桂[3] 汪洋 王江营[1] 张如强[4] 杨志明 张贵金 LI Yi;HU Langui;WANG Yang;WANG Jiangying;ZHANG Ruqiang;YANG Zhiming;ZHANG Guijin(School of Hydraulic Engineering,Changsha University of Science and Technology,Changsha 410114;Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province,Changsha University of Science andTechnology,Changsha 410114;Hunan Lishui Hydrg ＆ Power Co.,Ltd.,Changsha 410007;Hunan Centianhe Engineering Construction Investment Corporation,Yongzhou 425500;Hunan Hydropower Design Institute,Changsha 410007)

机构地区：[1]长沙理工大学水利工程学院,长沙410114 [2]长沙理工大学水沙科学与水灾害防治湖南省重点实验室,长沙410114 [3]湖南澧水流域水利水电开发有限责任公司,长沙410007 [4]湖南涔天河工程建设投资有限责任公司,永州425500 [5]湖南省水利水电勘测设计研究总院,长沙410007

出　　处：《工程地质学报》2018年第4期1095-1104,共10页Journal of Engineering Geology

基　　金：国家自然科学基金(51509022;51508039)资助

摘　　要：涔天河水利枢纽扩建工程1#泄洪洞出口段开挖断面大、坡度较陡、围岩风化程度高、洞口偏压严重。由于受持续强降雨影响,隧洞出口段上半洞开挖完以后,洞口边墙围岩及洞顶仰坡出现了系统性拉裂现象,导致工程停工。为尽快恢复施工,保障水库按时下闸蓄水,在原有支护措施基础上提出了一系列增强加固支护措施,并增加洞室及边坡变形监测。通过建立能反映真实施工过程的大型三维计算模型,利用初期变形监测数据,对围岩的变形参数进行初步估计,并预测了隧洞出口下半洞及出口明渠基础开挖产生的变形情况,初步研究表明,在初设与增强加固支护措施的保护下,洞口及边坡的总体安全性可以得到保障,研究成果促进了工程恢复施工。而后,结合新增的由于隧洞出口下半洞及出口明渠基础开挖产生的变形监测数据,对施工开挖进行了全过程反演分析,获得了更为准确的岩土体变形参数,变形监测数据与数值模拟结果吻合良好,说明了反演分析的可靠性。最后,对工程永久衬砌施工进行模拟,计算了工程完工后永久衬砌新增变形量,并对衬砌应力进行了安全校核。本文研究成果对工程快速恢复施工及水库按时蓄水泄洪产生了较为重要的作用。The No.1 spillway tunnel outlet of Centianhe project has large excavation section,steep slope,strongly weathered surrounding rocks and high unsymmetrical rock stresses. After the excavation of the upper part of thetunnel,the construction had to be stopped since the heavy rainfall induced cracks were found in the tunnel sidewall and the outlet slope. More reinforcement and monitoring measures were designed to help restarting the construction quickly,and then to insure that the reservoir could store water on time. A three dimensional calculation mesh was built to accurately reflect construction progress. The monitoring results of initial stage were adopted to estimate the mechanical parameters of the surrounding rocks,which were then used to predict the subsequent deformation and stability of the slope and tunnel. The results showed that the deformation induced by later excavation could be controlled under the enhanced reinforcement measures and the subsequent construction could be safe. The measured deformation increment induced by the subsequent excavation of the lower half of the tunnel and the open channel foundation was used to conduct the back analysis. The calculated results agreed very well with the monitoring data.Then the stress of the lining was predicted. This study helped restarting the construction of the tunnel,and also benefited the water storage and flood discharge of the reservoir.

关 键 词：涔天河工程 偏压隧洞 变形 裂缝 监测 

分 类 号：U452.12[建筑科学—桥梁与隧道工程]