An earthquake is a sudden motion or trembling of the ground caused by unexpected breaking and shifting of large sections of the Earth’s outer shell due to an abrupt release of slowly accumulated strain.
Seismic standards and codes designed to reduce the probability of building collapse to low and acceptable limits by providing for potential earthquake loading through the requirements that structures are designed to resist specified static lateral forces. Alternatively, the structures are designed under dynamic analysis guidelines stated in the standards
An investigation has been conducted to see how well seismic standards and codes reflect the loadings of real earthquakes.
It has been found that under the dynamic loadings specified in the standards underestimate the loadings of the earthquakes.
However, the static analysis stated in the standards is sufficient for earthquake design.