JIA Hong-jun, WANG Hui. Principle and application of the double cacheable and gradually deformable supporting shells for soft rock tunneling[J]. 2015, 36(4): 1119-1126.
DOI:
JIA Hong-jun, WANG Hui. Principle and application of the double cacheable and gradually deformable supporting shells for soft rock tunneling[J]. 2015, 36(4): 1119-1126.DOI: 10.16285/j.rsm.2015.04.028.
Principle and application of the double cacheable and gradually deformable supporting shells for soft rock tunneling
The large rheological deformation of surrounding rock caused by the high ground stress is an important factor that affects the safety and stability of deep soft roadways. Deformation and failure mechanism of weak surrounding rock at the west roadway of Coal Mine of Yangquan Coal Mining Group No.1 are analysed. A finite element model is developed which can address the local geological conditions and the initial design scheme. Based on the field monitoring deformation data and rock borehole results
the mechanical parameters and creep parameters of the surrounding rock are obtained through a back analysis. A new support scheme
which consists of double cacheable and gradually variable supporting shells
is proposed for deep soft-rock tunnelling. The scheme is implemented through hierarchically grouting reinforcement according to the damage condition of the surrounding rock and setting up a U-steel support in the external area to form deformable buffer layer. Finite element method for simulating the new support scheme is developed. Using the parameters obtained from the back analysis
deformation of surrounding rock is predicted. By comparing the numerical results with the field monitoring data
the effectiveness of the new support scheme is verified.