管片-豆砾石-围岩组合结构承载特性分析

Analysis of the bearing characteristics of the segment-bean gravel-surrounding rock combination structure

摘要

管片-豆砾石-围岩组合结构是TBM有压输水隧洞的主要承载结构，以湖北某输水隧洞TBM段为研究对象，建立管片-豆砾石-围岩组合结构三维有限元数值分析模型，研究考虑开挖荷载释放影响条件下组合结构内压承载特性。结果表明：考虑部分开挖荷载释放情况下管片整体应力、接缝开度、螺栓应力均较小，更有利于管片承担内水压力；斜螺栓附近为裂缝出现主要位置，是否考虑开挖荷载释放会影响裂缝分布；内水压力作用下，楔形封顶块位置会影响管片螺栓的应力分布，靠近封顶块同一接缝处螺栓应力差异明显；组合结构中内水压力主要由围岩承担，豆砾石几乎不承担内水压力，管片仅在内水压力较小时承担少量内水压力。

Abstract

The combined structure of segment-bean gravel-surrounding rock is the main bearing structure of TBM with pressure water transmission tunnel. Taking the TBM section of the water transmission tunnel in Hubei as the research object, the three-dimensional finite element numerical analysis model of segment-bean gravel-surrounding rock combined structure is established, and the internal pressure bearing characteristics of the combined structure under the influence of excavation load release are considered. The result show that considering the overall stress, joint opening and bolt stress in the case of partial excavation load release, it is more beneficial to the segment to bear the inner water pressure; the main location near the inclined bolt will affect the crack distribution; the wedge cap affects the stress distribution of the segment bolt under the inner water pressure, and the internal water pressure under the inner water pressure.

关键词

管片-豆砾石-围岩组合结构 / TBM / 承载特性 / 内水压力 / 围岩

Key words

segment-bean gravel-surrounding rock combination structure / TBM / bearing characteristic / inner water pressure / surrounding rock

Author summay

刘 麟(1976—), 女, 高级工程师, 硕士, 主要从事水工结构设计工作。E-mail: [e-mail]