Abstract: A fullscale model test method for water pressure resistance of lining structure is proposed for New Yuanliangshan tunnel passing through highpressure waterrich karst areas. To validate the water pressure resistance of the tunnel lining structure, the external water pressure born by tunnel lining is transformed into internal water pressure. Then through numerical simulation results using realistic failure process analysis(RFPA) system, the conversion relation of different models′ hydraulic safety factors is established. The results show the following: (1) The ultimate hydraulic resistance of tunnel lining structure under external uniform water pressure and local water pressure is 1.44 and 0.67 times of the ultimate hydraulic resistance of fullscale model test, respectively. (2) The water pressure resistance of karst cave transitional section lining (K2.0) is 3.33 MPa, and that of the karst cave section lining (K3.0) is no less than 5.33 MPa, indicating the K2.0 and K3.0 lining of construction joints is reasonable for New Yuanliangshan tunnel, and meeting the water pressure resistance of the design requirements.

Key words:  karst tunnel; lining structure, construction joint, fullscale model test, water pressure resistance