分块掘进工序对偏压隧道围岩变形及结构受力的影响分析
Analysis of the Surrounding Rock Deformation and Structural Stress on the Bias Tunnel by Block Excavation Sequence
高晨 1史魏 1于洋 1胡冲 2莫楠 1黄震2
作者信息
- 1. 中国建筑第七工程局有限公司,河南 郑州 450003
- 2. 广西大学土木建筑工程学院,广西 南宁 530004
- 折叠
摘要
以融福高速公路振彩隧道为工程背景,提出预留核心土下台阶分块开挖法,采用FLAC3D有限差分程序进行三维仿真分析,对比分析预留核心土下台阶分块法、传统预留核心土法和中隔墙法的围岩变形及支护结构受力,并探讨其合理开挖顺序.研究结果表明:隧道在浅埋偏压条件下,围岩变形及结构受力呈不对称性,地表沉降最大值均出现在隧道中心偏深埋侧,拱肩和拱腰竖向位移均表现为深埋侧大于浅埋侧;预留核心土下台阶分块法先开挖浅埋侧的地表沉降、拱顶沉降和锚杆轴力最大值均小于传统预留核心土法,有利于控制围岩及支护稳定性;中隔墙法先开挖深埋侧对地表沉降和围岩竖向位移控制较优,而先开挖浅埋侧对水平位移控制较优,衬砌结构受力较小.
Abstract
Based on the engineering background of Zhencai Tunnel of Rongfu Expressway,the block excavation method of reserved core soil lower step is proposed.The FLAC3D finite difference program is used for three-dimensional simulation analysis.The surrounding rock deformation and supporting structure stress of the reserved core soil lower step block method,the traditional reserved core soil method and the middle partition wall method are compared and analyzed,and the reasonable excavation sequence is discussed.The results show that the surrounding rock deformation and structural stress of the tunnel are asymmetric under the condition of shallow buried bias.The maximum surface settlement occurs on the deep buried side of the tunnel center,and the vertical displacement of the arch shoulder and the arch waist is larger on the deep buried side than the shallow buried side.The surface settlement,vault settlement and the maximum axial force of the bolt in the shallow buried side by the reserved core soil lower bench block method are smaller than those by the traditional reserved core soil method,which is beneficial to control the stability of surrounding rock and support.The middle partition wall method is better to control the surface settlement and the vertical displacement of the surrounding rock by excavating the deep buried side first,while the shallow buried side is better to control the horizontal displacement and the lining structure is less stressed.
关键词
隧道工程/工法优化/围岩/变形/结构受力/数值模拟Key words
tunnels/method optimization/surrounding rock/deformation/structural stress/simulation引用本文复制引用
出版年
2024
NETL
NSTL
万方数据