Peak Ground Acceleration

In design of earthquake resistant structures peak ground acceleration (PGA) is frequently mentioned. This is because acceleration is considered a measure of  force, and is easy to comprehend. While PGA is said to be the design parameter, other components of ground motion (peak values of ground velocity and displacement, duration of strong motion, frequency content of the vibration etc.) are equally important.

Empirical Relationships For Estimating Peak Ground Acceleration.

Earthquake resistant structures are designed against an hypothetical earthquake, called the Design Basis Earthquake, Which is specified by its location and magnitude. This information is then required to be converted into the ground motion parameters ,e.g. peak values of ground acceleration, Velocity and displacement. Empirical relationships have been derived fro data on past earthquakes estimate the peak values of the ground motion parameters for different earthquake environments. Selecting a suitable empirical relationship for estimating the peak values of the ground motion parameters is an important step in earthquake resistant design.

References for the empirical relationships:

C-Codes For Empirical Relationships for PGA