Numerical Investigation of the Support System of Qiongzhong Underground Powerhouse Cavern

Three-dimensional distinct element method is used to study the excavation and supporting system of the cavern group of Qiongzhong Pumped Storage Power Station in China. The loading of anchor system is in good agreement with the deformation of the surrounding rock. The deformation of the specific location is large; corresponding anchor bolt force is relatively large. The force distribution of the systematic bolts and cables after the final excavation shows that the supporting system is safe under the support scheme of construction. The parts closing yield state mainly distribute in the vicinity of the intersection of discontinuities, especially in the vicinity of the 1 # Set. Because of several anchors are canceled, the load of anchors in the surrounding rock of 1 # Set and 2 # Set increases about 5% compared with the design support scheme.