3D seismic response assessment of barrette piled high-rise building with comprehensive subsurface modelling

Abstract

The increased popularity of using barrette piled foundations for high-rise buildings has brought about a need to fully comprehend how the complete integrated system of soil, piles and superstructure is simulated realistically by 3D non-linear finite element (FE) models responding to the seismic excitation in time-domain. Subtle details of physical and spatial 3D soil variation are modelled by the novel image processing technique allowing more realistic subsurface geotechnical modelling. The borehole data from the site-specific investigation have been considered to reduce the epistemic uncertainties in 3D FE soil models. Paper adapts this advanced subsurface modelling technique to 3D seismic response analysis to enable more accurate predictions of the geotechnical seismic design process by explaining how 3D varying subsurface boundaries are represented by viscous damping in 3D seismic interaction analysis. 3D FE simulations subjected to bilateral seismic excitation have been performed representing the free-field boundaries, material damping and the penalty frictional contact algorithm for the pile-soil interface. It tackles the important aspect of this practical problem by exploring the deformation and the acceleration responses of soil, piles and superstructure in terms of the linear and nonlinear analyses. Paper reveals that the seismic responses are markedly affected by bilateral seismic excitations, nonlinearity and 3D lithological soil variation.