关键词: 深埋隧洞, 爆破开挖, 地应力重分布, 数值模拟, 高地应力

Abstract: The stress evolution law of surrounding rock during continuous blasting excavation in deep underground tunnel with high geostress is studied by ANSYS/LS-DYNA dynamic finite element software model. By comparing and analyzing the results of two working conditions, namely quasi-static stress redistribution, and ground stress redistribution coupled with blasting load, the evolution law and influential factors of stress evolution of surrounding rock under continuous blasting are obtained.Shear failure is the main failure pattern. The redistribution of stress is the main reason for the change of stress field in the surrounding area of the tunnel; blasting load only affects the surrounding rock stress in the adjacent of explosive holes by inducing damage. In the research case of this paper, continuous excavation unloading only affects the surrounding rock in the range of about four meters behind the working face, and after two successive footages, the stress field of surrounding rock of the tunnel is basically stable.

Key words: deep-buried tunnel, blasting excavation, in-situ stress redistribution, numerical simulation, high geostress