A stochastic approach for generating spectrum compatible fully nonstationary earthquakes

Simulation of artificial earthquakes in agreement with the provision of international seismic codes is addressed. Due to the importance of nonstationary frequency content on the seismic assessment of structures, in this paper a new method for generating spectrum compatible fully nonstationary earthquakes is proposed. The method assumes that the ground motion is modeled by the superposition of two contributions: the first one is a fully nonstationary counterpart modeled by a recorded earthquake; the second one is a corrective random process adjusting the recorded earthquake in order to make it spectrum compatible. Several examples show the accuracy of the proposed method.