Formal extensions of the response spectrum method to include spatial seismic effects are reviewed. Two approaches are described in detail: the first based on random vibrations of a simple oscillator under two-component excitations, and the second analyzing multi-column building seismic response. The subjective choice of these two complementing approaches aims at analyzing the phenomenon of spat...

The identification of the limiting factors in the dynamical behavior of complex systems is an important interdisciplinary problem which often can be traced to the spectral properties of an underlying network. By deriving a general relation between the eigenvalues of weighted and unweighted networks, here I show that for a wide class of networks the dynamical behavior is tightly bounded by few n...

The common modeling assumptions in analyses of structural response considering the effects of soil-structure interaction are discussed, as well as their consequences. Issues such as spatial variability of strong ground motion and flexibility of building foundations are specifically addressed. Results are shown for the case when spatial variability is considered, but inertia interaction and kine...

As it is stated in the ISO 18431-4 Standard, a Shock Response Spectrum is defined as the response to a given acceleration acting at a set of mass-damper-spring oscillators, which are adjusted to the different resonance frequencies while their resonance gains (Q-factor) are equal to the same value. The maximum of the absolute value of the calculated responses as a function of the resonance frequ...