Seismic slope behavior in a large-scale shaking table model test

In this research large-scale shaking table model tests were conducted to study slope behavior under earthquake conditions. The model slope was installed into a model box with a length of 4.4 m, width of 1.3 m, and height of 1.2 m. A uniform medium sand was used and the specimen was reconstituted using the controlled-volume compaction and with a water content of 8% and unit weight of 16.6 kN/m3. The size of the model slope is 0.5 m high, 1.3 m wide, and with a slope angle of 30°. The boundary and model slope were analyzed before testing using numerical analysis to verify the boundary conditions of the box and to ensure the proper lay-out of the model slope. The law of similitude after Iai [Iai, Suzumu (1989), Similitude for shaking table tests on soil-structure-fluid model in 1-g gravitational field, Soils and Foundations, v. 29, No. 1, pp. 105-118] and Meymand [Meymand, Philip J. (1998), Shaking Table Scale Model Tests of Nonlinear Soil-Pile-Superstructure Interaction in Soft Clay, Ph.D. dissertation, U.C. Berkeley] was applied for the determination of loading conditions. The rigidity of the model box was then calibrated accordingly.A series of tests was performed with the designated loading frequency and amplitude. The responses of the slope remained linear with a loading amplitude of up to 0.4 g and a frequency of 8.9 Hz. Nonlinear responses were observed when the loading amplitude became larger than 0.5 g. The failure surface appeared to be fairly shallow and confined to the slope surface, which was consistent with the field observations of earthquake-induced landslides.With such a model test with proper consideration of the law of similitude, the response and amplification behavior of a prototype slope can be studied in the laboratory. Such information could be used for further evaluation of the slope failure caused by an earthquake in the field, and for the study of the behavior of important slopes such as earth dams under seismic loading conditions.