Scholarlink

<p>Weak interlayers are common structural discontinuities in tunnel surrounding rock, yet their quantitative effects on stress redistribution, progressive failure, and pressure arch evolution remain insufficiently understood. This study investigates the deformation and failure mechanisms of tunnels in surrounding rock containing weak interlayers through physical model tests and three-dimensional numerical simulations. The results show that weak interlayers significantly amplify tunnel deformation and accelerate progressive failure. The final vertical displacement of the weak-interlayer model increases from 0.024&#xa0;mm to 0.857&#xa0;mm with increasing load, and its crown settlement reaches 1.35 times that of the homogeneous model during the early failure stage. After excavation, the radial stress reduction rate reaches 76.32%, indicating intensified stress release and redistribution. Numerical results show that increasing the weak-interlayer dip angle changes the stress transfer path from a nearly symmetrical pattern to an asymmetrical mode controlled by the weak structural plane. The pressure arch thickness is strongly affected by the weak-interlayer position and dip angle. These findings clarify the mechanical link among weak-interlayer geometry, stress redistribution, and tunnel instability, providing a basis for targeted support design.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Deformation and failure characteristics of tunnels in surrounding rock with weak interlayers: Insights from physical model tests and numerical investigations

  • 期刊论文

  • 发表日期：

    2026年6月27日

查看全文
  • Fan Ding,
  • Xiang Fan,
  • Yongli Xie,
  • Wenjie Li,
  • Wenwen Feng

摘要

Weak interlayers are common structural discontinuities in tunnel surrounding rock, yet their quantitative effects on stress redistribution, progressive failure, and pressure arch evolution remain insufficiently understood. This study investigates the deformation and failure mechanisms of tunnels in surrounding rock containing weak interlayers through physical model tests and three-dimensional numerical simulations. The results show that weak interlayers significantly amplify tunnel deformation and accelerate progressive failure. The final vertical displacement of the weak-interlayer model increases from 0.024 mm to 0.857 mm with increasing load, and its crown settlement reaches 1.35 times that of the homogeneous model during the early failure stage. After excavation, the radial stress reduction rate reaches 76.32%, indicating intensified stress release and redistribution. Numerical results show that increasing the weak-interlayer dip angle changes the stress transfer path from a nearly symmetrical pattern to an asymmetrical mode controlled by the weak structural plane. The pressure arch thickness is strongly affected by the weak-interlayer position and dip angle. These findings clarify the mechanical link among weak-interlayer geometry, stress redistribution, and tunnel instability, providing a basis for targeted support design.