The Analysis of Accelerograms for the Earthquake Resistant Design of Structures

Abstract

In this paper, the analysis of ground motions (displacements, velocities and accelerations) has been performed focused to the seismic design. The relationships between the peak ground acceleration (PGA), the peak ground velocity (PGV), the peak ground displacement (PGD) and the bracketed duration, with the earthquake magnitude, are presented and their validity and applicability for seismic design is discussed. Finally, the dominant periods of the ground motions (displacement, velocity and acceleration) are obtained from their Fourier Spectrum. Their validity and applicability for the seismic design is discussed also. The results presented in this paper show that the relationships that exist between the important parameters: PGA, PGV, PGD and duration; and the earthquake magnitude, allow the prediction of the values for these parameters, in terms of the magnitude for future strong motions. These predictions can be very useful for seismic design. Particularly, the prediction of the magnitude associated to the critical acceleration, because the earthquakes with magnitude greater than this critical magnitude can produce serious damages in a structure (even its collapsing). The application of the relationships obtained in this paper must be very careful, because these equations are dependent on the source area, location and type of structure. The dominant periods of the ground motions (displacement, velocity and acceleration) that are computed and presented in this paper, are also important parameters for the seismic design, because recent studies have shown that the earthquake shaking is more destructive on structures having a natural period around some of these dominant periods. These parameters must also be handled with caution, because they show dependence with the source area, location and type of structure.

Calibration and Validation of a Seismic Damage Propagation Model for Interdependent Infrastructure Systems

“…As PGD values in the area are also absent from USGS or other sources, these values are estimated using the relationship described in Theodulidis and Papazachos (1992): where MMI is the modified Mercalli intensity that captures local seismic demands, S is set to 0 for alluvial soils, and P is set to 0 to indicate the 50th percentile level of the PGD value. Other methods of estimating PGD or repair rates include those described by Corchete (2010), Pineda-Porraz and Ordaz (2010), Margaris et al (2002), and Skarlatoudis et al (2003).…”