岩土力学2023，Vol.44Issue(11)：3128-3140,13.DOI:10.16285/j.rsm.2022.1726
硬岩开挖诱发扰动应力旋转规律及其对岩体破裂的影响
Law of disturbed stress rotation induced by hard rock excavation and its influence on rock fracture
摘要
Abstract
The rock fracture caused by disturbed stress field change in deep underground engineering is a common issue receiving continuous attention.After analyzing the test data of disturbed stress field in Jinping underground laboratory phase Ⅱ project,the variation law of disturbed stress field under different construction processes was interpreted,and the change mode of principal stress direction was analyzed.Through the comparative analysis about in-situ drilling imaging of rock mass,the influence of principal stress direction change on surrounding rock fracture was revealed.The results show that the disturbed stress field changes the most actively at the stage of middle drift excavation,the change mode of principal stress direction is mainly gyration when the tunnel face is advancing toward the monitoring section,and the change mode is mainly rotation when the tunnel face moves away from the monitoring section.The position where the principal stress direction change reaches the maximum is 4.5 meters away from the sidewall.During the expanded excavation of sidewall,the change mode of principal stress direction is mainly rotation,and the position where the change reaches the maximum is 2.5 meters away from the sidewall.The change in disturbed stress direction directly affects the pattern and trend of rock fracture development,the stress with large-angle rotation tends to cause tensile crack and tensile-shear mixed crack,and the stress with small-angle rotation tends to cause the shear crack with concave and convex morphological features whose deflection angle equals the stress rotation angle.The stress with large-angle gyration mostly causes X-shaped shear crack.The results based on the measured disturbed stress can provide a reference for studying the variation law of disturbed stress field during deep high-stress hard rock excavation and its influence on rock facture development.关键词
深部岩体/硬岩开挖/扰动应力/应力方向/岩体破裂Key words
deep rock mass/hard rock excavation/disturbed stress/stress direction/rock facture分类
土木建筑引用本文复制引用
孙钱程,刘越,王庆文,李邵军,郑民总..硬岩开挖诱发扰动应力旋转规律及其对岩体破裂的影响[J].岩土力学,2023,44(11):3128-3140,13.基金项目
国家自然科学基金资助项目(No.51909136,No.42202320).This work was supported by the National Natural Science Foundation of China(51909136,42202320). （No.51909136,No.42202320）
