Velocity and displacement records are obtained from strong-motion acceleration records with numerical integration and low-cut filters.
A suite of nine ground motion acceleration time history records, representing a wide range of intensity and frequency contents, are selected and used in the study.
A suite of nine-ground motion acceleration time history records, representing a wide range of intensity and frequency contents, is selected and used in the study.
According to the site condition and seismic background, two scaled ground motion accelerations, the recorded El Centro acceleration (ELA) and the artificial acceleration adopted in Guangzhou (GZA), are employed as the seismic excitations.
A series of testing cases of the shaking tables were carried out on the model soil site and tunnel using input motions with different earthquake acceleration records and seismic amplitudes.
Fourier spectra of two horizontal motions were calculated using the acceleration records with a duration of 81.92 s including S-wave portion.
In the present study, we collected 48 near-fault acceleration records to derive strong ground motion parameters in terms of the peak ground acceleration, peak ground velocity, peak spectrum acceleration (5% of the damping ratio) and spectrum intensity (5% of damping ratio).
The present study adopted the stochastic method to determine the peak ground motion (acceleration, velocity and displacement) for the three largest earthquakes recorded in the Egypt's seismological history.
Open image in new window Fig. 5 Acceleration records of accelerometers at various depths during shake table experiment on Ganga sand for: a motion 1, b motion 2 and c motion 3. Since the soil box is small, in order to effectively use the experimental results for predicting the response of a prototype deposit, well-justified similitude rules have to be adopted.
Evaluation of the acceleration records have shown low amplitude but long period and long duration motions at Istanbul.
It is found that a large number of noisy acceleration records that are usually discarded from sets of records used for estimating the ground motions can be corrected using this new method.
