Shaking table test on liquefaction characteristics of foundation around a complicated subway station with diaphragm walls

The external profile of the underground structures and the annexes which greatly change the lateral stiffness of the whole structures have significant influences on the seismic performance, deformation behavior and failure characteristics of the main structures. Large-scale shaking table model tests on the dynamic interaction system of liquefied site-diaphragm wall-complicated subway station are carried out. The test results of the development of pore water pressure, acceleration of model system, earthquake-induced ground settlement and structure uplifting are compared and analyzed. It is shown that the underground structures and the diaphragm walls have great effects on the earthquake responses of soil foundation around the structures, which are also affected greatly by the liquefaction condition of soil foundation. The model system is more responsive to the low frequency of ground motion, and the acceleration response spectrum moves towards the long period with the increase of the seismic excitation intensity. Although the station and model site suffer from subsidence when subjected to small seismic vibration, the underground structure system appears to rise obviously under the action of strong seismic loading. In addition, the distribution of pore water pressure and its development process of the model foundation are roughly the same along the longitudinal structure. As a result, the effects on the dynamic pore water pressure are also analyzed.