The layered interval excavation method for a large span and high sidewall underground cavern is described in detail. Through numerical simulation

its feasibility is proved. A large span and high sidewall cavern construction practice is as follows; detailed large cavern reserved rock clapboard

upper

middle and bottom chamber between rock clapboard parallel excavation

and finally clear the rock clapboard full of this new method of construction of the excavation process. Through numerical simulation

the largest deformation caused by excavation

distribution of plastic zone and tension of rock bolting of two excavation methods are compared. The results show that the new method of rock excavation damage to surrounding rock is small. Finally

the applicable conditions for this new method are pointed. This method has universal significance for similar conditions of underground large cavern construction.