This Presidential Young Investigator Award includes research in structural engineering and reliability. Research includes computer- based reliability analysis with special emphasis on systems with nonlinear dynamic response and hierarchical damage states, development of a hybrid reliability approach applied to seismic response and fatigue crack growth. The traditional approach to such problems is not applicable since explicit relationships between loading and response parameters are not available. For complicated load and response models such as nonstationary ground acceleration and seismic damage, an explicit relationship does not exist. Complete simulation to establish the reliability in such cases is impractical due to the number of random variables involved. Through such studies, an attempt will be made to integrate simulation and advanced reliability methods to solve multidimensional, nonstationary, nonlinear, time-dependent reliability problems. Methods developed will have an impact on many areas in structural engineering including the design of buildings for wind and seismic effects, design and development of offshore structures, aeronautical and space structure design and nuclear plant design.
