Free-field soil response to bidirectional horizontal non-uniform ground motion from multi-point shaking table tests

This paper assesses the dynamic nonlinear free-field soil response under bidirectional horizontal non-uniform excitation through a series of multi-point 1 g shaking table tests. The bed was enclosed in an innovative box supported by array three shake tables and subjected to uniform ground motions one two directions. unidirectional excitations, both non-uniform, were compared discussed terms acceleration time history Fourier spectra, amplification factor settlement, as well shear stress-shear strain behavior. comparison responses shakings demonstrated that trends peak factors are similar along depth, but difference between is increasingly higher profile towards surface, especially for excitation. variations stress-strain damping curves longitudinal excitation; however, they much different than those observed transverse Y-direction larger These site characteristics should be properly considered seismic design extended infrastructure.