Seismic risk assessment through strong ground motion and vulnerability

In engineering seismic hazard and seismic risk are two main concepts in evaluating the performance of a structure during an earthquake. These concepts differ from each other. Seismic hazard is expressed by the probability of occurrence of a specific seismic event. Meanwhile seismic risk means the expected consequences of the seismic events which is related to the loss of people life, wounding and eventual economic losses. To enable the engineering analysis of seismic risk, we use the concept of vulnerability (V) and the characteristics of the strong-ground motion. Through the vulnerability, we express the degree of damage to the building, assessed these on the size of the earthquake, the intensity I, or its acceleration ag. The seismic ground-motion is the basic input to earthquake-resistant design and the evaluation of collateral seismic hazards.