The shape and the amplitude of the design spectrum are critical to the safe design of structures. This paper presents suggested changes to the shape constraints for the design spectrum in the 0.5 to 3 Hz range for large intraplate earthquakes. The main recommendation arises because of the impact on a large pulse loading within an intraplate earthquake with a frequency of 1 to 2 Hertz. Newmark a...

amplitudes of seismic waves decrease with distance according to anelastic properties of the earth and geometrical spreading. the attenuation of ground-motion amplitudes in the frequency domain is an important problem in engineering seismology. it is of particular practical interest in the regions such as zagros (iran). the zagros fold- thrust belt, as a part of alpine- himalayan orogenic belt i...

When ambient seismic waves pass near and under an interferometric gravitational-wave detector, they induce density perturbations in the Earth, which in turn produce fluctuating gravitational forces on the interferometer’s test masses. These forces mimic a stochastic background of gravitational waves and thus constitute a noise source. This seismic gravity-gradient noise has been estimated and d...

This study investigated seismic ground motion intensity to estimate the damage rates of low- and middle-rise RC buildings due various earthquakes. It calculated vulnerability functions analytical models for earthquake motions with different spectral characteristics evaluated effects on functions. The results confirmed that average acceleration response spectrum periodic band corresponding prima...

[1] Noise with periods 3 to 10 s, ubiquitous in seismic records, is expected to be mostly generated by pairs of ocean wave trains of opposing propagation directions with half the seismic frequency. Here we present the first comprehensive numerical model of microseismic generation by random ocean waves, including ocean wave reflections. Synthetic and observed seismic spectra are well correlated ...

Abstract—One good analysis method in seismic response analysis is direct time integration, which widely adopts Rayleigh damping. An approach is presented for selection of Rayleigh damping coefficients to be used in seismic analyses to produce a response that is consistent with Modal damping response. In the presented approach, the expression of the error of peak response, acquired through compl...

In this paper a local Radon representation is proposed and applied to 3-D seismic data analysis. The derivation of the local Radon power spectrum is based on an extension of the relation between the global Radon transform and multi-dimensional Fourier transform to the non-stationary case. This Wigner-Radon power spectrum is closely related to the Cohen’s class of quadratic timefrequency represe...