Scholarlink

<p>Deeply buried tunnels excavated in layered soft rock are prone to large deformation and floor heave under complex geological conditions. To address this challenge, this study investigates a combined support system consisting of a constant resistance large deformation (CRLD) anchor cable and a steel truss through physical model tests, numerical simulations, and field applications. Physical model test results indicate that CRLD anchor cables maintain the surrounding rock in a predominantly compressive state and promote more stable strain evolution compared with the unsupported condition, demonstrating their capacity to accommodate rock deformation through flexible buffering effect. Numerical simulations based on the discrete fracture network and discrete element method (DFN–DEM) reveal that, under different bedding inclination angles, the combined support system effectively coordinates deformation and stress redistribution within surrounding rock, achieving a mechanism of “flexible control and rigid constraint.” A field application in a layered soft rock tunnel with a burial depth of 456&#xa0;m and a bedding inclination of 30° demonstrates that the proposed support system reduces overall deformation and floor heave by approximately 50% compared with the conventional bolt–shotcrete–mesh–steel arch support scheme, while promoting a more uniform stress distribution throughout the support structure. Monitoring results show that the maximum vault and invert displacements are limited to less than 128&#xa0;mm, and the stresses in all support components remain below their yield strengths. These results confirm the effectiveness of the proposed support system for controlling large deformation in layered soft rock tunnels.</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

Study on anchor cable and steel truss support for large deformation in deep-buried layered soft rock tunnels

  • 期刊论文

  • 发表日期：

    2026年6月19日

查看全文
  • Bo Zhang,
  • Kang Yang,
  • Yi Yang

摘要

Deeply buried tunnels excavated in layered soft rock are prone to large deformation and floor heave under complex geological conditions. To address this challenge, this study investigates a combined support system consisting of a constant resistance large deformation (CRLD) anchor cable and a steel truss through physical model tests, numerical simulations, and field applications. Physical model test results indicate that CRLD anchor cables maintain the surrounding rock in a predominantly compressive state and promote more stable strain evolution compared with the unsupported condition, demonstrating their capacity to accommodate rock deformation through flexible buffering effect. Numerical simulations based on the discrete fracture network and discrete element method (DFN–DEM) reveal that, under different bedding inclination angles, the combined support system effectively coordinates deformation and stress redistribution within surrounding rock, achieving a mechanism of “flexible control and rigid constraint.” A field application in a layered soft rock tunnel with a burial depth of 456 m and a bedding inclination of 30° demonstrates that the proposed support system reduces overall deformation and floor heave by approximately 50% compared with the conventional bolt–shotcrete–mesh–steel arch support scheme, while promoting a more uniform stress distribution throughout the support structure. Monitoring results show that the maximum vault and invert displacements are limited to less than 128 mm, and the stresses in all support components remain below their yield strengths. These results confirm the effectiveness of the proposed support system for controlling large deformation in layered soft rock tunnels.