Numerical evaluation of a yielding tunnel lining support system used in limiting large deformation in squeezing rock

摘要: Large deformation in squeezing soft rock is a significant challenge that complicates the safety of underground construction engineering. A yielding tunnel support system allows certain amount over-excavation, thereby accommodating large severely rock. In this study, special has been developed with type newly foamed concrete material which cushion effect. The uses pre-cast blocks are mounted primary lining, and an situ cast layer placed between lining secondary lining. effect on tunnels validated by comparing numerical results those lining-strengthened stiff system. incorporation can both reduce maximum minimum principal stress Relative to support, about 50 60% respectively, improving state Further, compared plastic zone significantly improved, deformations at roof sides 40 46% less than resulting better