My research in probabilistic structural dynamics focuses on studying the effects of temporal variations in the frequency content of earthquake ground motions on the dynamic response of structures. To account for the uncertainties that are inherent in the definition of ground motions, the latter are modeled as nonstationary stochastic processes. The long-term objective of this research is to improve the reliability of seismic codes for designing safer and more economic structures by correlating structural damage with ground motion parameters.

In structural dynamics, system identification consists of estimating the dynamic characteristics of structures and their external loading based on recordings of their vibration. The objectives for developing system identification techniques are to use them for assessing the accuracy of analytical structural models, for evaluating nondestructive methods for detecting structural damage, and for active structural control. I am applying these techniques to deepwater, fixed offshore platforms. My research in structural reliability focuses on the development of finite element reliability methods and their practical application for linear and nonlinear dynamic problems. This probabilistic version of the finite element method deals with random field representation of material properties, geometry, and loads. I am employing these methods to analyze the seismic reliability of concrete gravity dams.