Seismic behaviour of shallow foundations: Shaking table experiments vs numerical modelling

Abstract

SUMMARYThe capability of a simplified approach to model the behaviour of shallow foundations during earthquakes is explored by numerical simulation of a series of shaking table tests performed at the Public Works Research Institute, Tsukuba, Japan. After a summary of the experimental work, the numerical model is introduced, where the whole soil-foundation system is represented by a multi-degrees-of-freedom elastoplastic macro-element, supporting a single degree-of-freedom superstructure. In spite of its simplicity and of the large intensity of the excitation involving a high degree of nonlinearity in the foundation response, the proposed approach is found to provide very satisfactory results in predicting the rocking behaviour of the system and the seismic actions transmitted to the superstructure. The agreement is further improved by introducing a simple degradation rule of the foundation stiffness parameters, suitable to capture even some minor details of the observed rocking response. On the other hand, the performance of the model is not fully satisfactory in predicting vertical settlements.

Effects of Equipment-Structure-Soil Interaction on Seismic Response of Equipment and Structure via Real-Time Dynamic Substructuring Shaking Table Testing

“…Based on the design parameters, an equipment-structurenonlinear soil model was constructed via the ANSYS, and an equipment-structure-reduced one was created in MATLAB using (5). Then the equation of motion was solved via the Newmark-direct integration method.…”

“…Most studies of the ES subsystem were based on the rigid foundation assumption with no account taken of the soil effect, which is at odds with engineering reality and impairs the seismic performance research validity. The soil-structure interaction problem had also been investigated by using the shaking table test [3][4][5] and numerical analysis of soilstructure interaction [6][7][8]. These studies treated soil and structure as a fully coupled interaction system to elucidate the interaction effects.…”

Large Scale Soil-Foundation-Structure Model in Greece: Dynamic Tests vs Fem Simulation

“…Soil-structure interaction (SSI) has been widely investigated since the 1970s by means of theoretical approaches [1,2,3], field and laboratory studies as well as numerical modelling [4,5,6,7,8,9,10,11,12,13].…”

“…As for field and laboratory studies, SSI phenomena are commonly studied in small-scale by implementing experiments in shaking-table or centrifuge apparatuses [14,10,11,15,16]. Laboratory studies are particularly invaluable for the known initial and boundary conditions, and for the large quantity of applied instrumentations.…”

“…FE modelling allows a realistic evaluation of coupled soil-foundation-superstructure system, in terms of initial and boundary conditions, soil profile, geometry, nonlinearity of soil and/or soil-foundation interface [17]. FEM modelling, combined with field and laboratory tests, is the most useful tools for investigating the complexity of SSI [18,19,20,21,22,23,24,25,26,27,28,29,30].…”