During the 1995 Kobe earthquake, damages were observed in the Daikai subway station and adjacent tunnels. It was the first large-scale underground structure that failed under the earthquake excitation. Numerical and experimental analyses have been conducted to study the failure process of the Daikai station. However, the issue of the scale ratio still exists in the shaking table tests of underground structures. In order to tackle this issue, a hybrid simulation technique is developed here to study the seismic performance of a typical subway station. Based on the previous research, it is found that the central column is the critical component of the structure. Therefore, a reinforced concrete central column is physically tested in the hybrid simulation process. On the other hand, the remaining parts of the structure and soil domain are numerically modeled at the same time. Four hybrid simulation cases are conducted with peak ground accelerations of 0.01 g, 0.1 g, 0.22 g, and 0.58 g. The test results of displacement and shear force are compared with the analytical results. Moreover, the good agreement between the test results and numerical results validate the accuracy of the proposed hybrid test method. After the hybrid simulation process, a quasi-static test is conducted to illustrate the mechanical properties of the central column after the earthquake excitation. main way to study the seismic performance of subway stations, especially for failure progress [3][4][5][6][7]. Such investigations give clues to the design of typical underground structures.Yasuo et al. [3] used the equivalent linearized constitutive model for soil modeling. The viscous boundary was selected at the bottom of the finite element (FE) model. The transmission boundary was selected laterally. The rigid beam element and elastic beam element were selected for the structure modelling. The results showed that the shear force of the center column reached the bearing capacity during the earthquake and brittle failure happened. Due to the damage of the concrete, the vertical bearing capacity of the central column decreased, and the thrust exceeded the bearing capacity, which caused the center column to fail. The upper end of the side walls and the upper roof reached the ultimate bending capacity after the center column crushed. Huo et al. [4] applied an equivalent linearized constitutive material for soil modelling. The rigid boundary was applied on the bottom side, and the free boundary was selected on the lateral sides. The results showed that the soil-structure stiffness ratio was significant in the seismic analysis. The station with a lower stiffness ratio suffered more severe damage. As the Daikai station was designed subject to static loading only, the stirrup reinforcement ratio was relatively low, and brittle failure occurred due to the insufficient shear capacity. After the shear failure, the compressive bearing capacity of the central column decreased. In fact, the Daikai station had a large span. After the center column failed, the enti...

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Soil station system seismic issues have been highly valued in recent years. In order to investigate the dynamic seismic behaviors of the intermediate column in soil station systems, a hybrid test of a soil station system was conducted. The soil station model was performed with OpenSees. Virtual hybrid simulation was fulfilled with adapter elements. A hybrid model, composed of the steel column specimen and the remainder numerical model, was assembled using the OpenFresco framework. An intermediate column was treated as the physical substructure, while the rest of the soil station system was treated as the numerical substructure in a hybrid simulation. The hybrid test results are compared with the analytical results. The data obtained from such tests show that the system can accurately reflect the mechanical properties of intermediate columns in soil station systems. A hybrid simulation would be a proper way to assess the seismic performance of a soil station system.

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