This preview shows pages 1–2. Sign up to view the full content.
By EMRAH YENİER
INTRODUCTION:
Intensity, frequency content and duration are the main characteristics of the
earthquake ground motions. These characteristics give information about the seismic
energy of the ground motion, at which frequencies most of the energy is focused and
length of the ground shaking. Many methods proposed in the literature to describe
these characteristics.
In this assignment, Sakarya ground motion record of 17 August 1999
earthquake is provided. This ground motion has peak ground acceleration, (PGA) of
399.365 cm/s
2
.
It is asked to plot the Fourier amplitude spectrum and response spectrum and
to determine the Arias intensity, Arias duration and Bracketed duration of the
provided ground motion.
Fourier Amplitude Spectrum (FAS):
Fourier amplitude spectrum, (FAS) is a result of Fourier transformation of the
ground motion. According to Fourier transformation, any random vibration can be
expressed by the combination of sine waves with different frequencies, amplitudes
and phases. Fourier amplitude spectrum is a plot of frequencies versus the
corresponding amplitudes. It gives information about the frequency content of the
ground motion and at which frequencies most of the seismic energy is concentrated.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview. Sign up
to
access the rest of the document.
 Fall '06
 Cetin

Click to edit the document details