地下水封洞库施工期洞室围岩变形松弛典型特征与规律  

Deformation-relaxation typical characteristics and laws of surrounding rock of underground water-sealed storage cavern during construction stage

作　　者：曹洋兵 江志豪 黄月 李尧 王东瑞 李兵磊[1,2] CAO Yangbing;JIANG Zhihao;HUANG Yue;LI Yao;WANG Dongrui;LI Binglei(Zijin School of Geology and Mining,Fuzhou University,Fuzhou,Fujian 350108,China;Fujian Provincial Universities Engineering Research Center of Geological Engineering,Fuzhou,Fujian 350108,China;Beijing New Oriental Star Engineering Investigation Design Co.,Ltd.,Beijing 100070,China)

机构地区：[1]福州大学紫金地质与矿业学院,福建福州350108 [2]地质工程福建省高校工程研究中心,福建福州350108 [3]北京东方新星勘察设计有限公司,北京100070

出　　处：《福州大学学报（自然科学版）》2024年第2期245-252,共8页Journal of Fuzhou University(Natural Science Edition)

基　　金：福建省自然科学基金资助项目(2023J01424);贵州省高层次创新型人才资助项目(黔科合平台人才[2020]6019-2)。

摘　　要：基于地下水封洞库工程特征与典型洞库工程实例,整理分析大量洞室围岩内部变形、表层变形、波速与锚杆应力等监测数据.结果表明:预埋的多点位移计测点位移主要为0.5~3.0 mm,收敛位移监测值主要为4~8 mm,拱顶沉降监测值主要为3~6 mm,围岩时效变形不明显;围岩变形与爆破开挖有关,当掌子面或后续台阶开挖面接近监测断面时,变形出现陡增;围岩质量越差,开挖面空间效应越不明显.提出洞室围岩损失位移确定方法,发现损失位移占最终收敛位移50%~60%;基于波速变化率提出围岩松弛程度评价指标,发现围岩最大松弛程度约为0.47,松弛深度为1.5 m;洞室围岩锚杆受力普遍较小,锚杆拉应力与围岩变形基本同步变化.Based on the engineering characteristics of underground water-sealed storage caverns and typical cases of storage caverns,a large number of monitoring data including internal deformation,surface deformation,P-wave velocity and bolt stress of surrounding rock of storage caverns were analyzed.The results show that:the displacement of the multi-point displacement meter embedded before excavation is mainly 0.5 to 3.0 mm,the convergence displacement is mainly 4 to 8 mm,and the settlement deformation of cavern vault is mainly 3 to 6 mm.The time-dependent deformation of surrounding rock is not obvious;the deformation of surrounding rock is mainly related to the blasting excavation.When the working face or the excavation face of the subsequent bench is closing to the monitoring section,the deformation increases sharply.The worse the quality of the surrounding rock is,the less obvious the spatial effect of the excavation surfaces.A method to determine the loss displacement of surrounding rock is proposed.It is found that the loss displacement accounts for 50%to 60%of the final convergence displacement.Based on the change rate of P-wave velocity,the evaluation index of surrounding rock relaxation degree is proposed.It is found that the maximum relaxation degree of surrounding rock is about 0.47,and the relaxation depth is 1.5 m.The stress of surrounding rock bolt in cavern is generally small,and the tensile stress of bolt changes synchronously basically with the deformation of surrounding rock.

关 键 词：水封洞库 施工期监测 围岩变形 损失位移 围岩松弛 

分 类 号：TU45[建筑科学—岩土工程]