Monitoring and Condition Assessment for Resilient Civil Infrastructure Systems

In 2008 the National Academy of Engineering published the treatise Grand Challenges for Engineering. This document summarizes the main issues that need to be addressed in the near future to advance the current state of our civilization, and to guarantee a sustainable progress towards an improved quality of life. Among the 14 Grand Challenges outlined we find the need to Restore and Improve Urban Infrastructure. In particular for the United States this grand challenge points out the outcomes of the American Society of Civil Engineers 2013 report card which rated the U.S. infrastructure with an overall grade of D+, and highlighted the need to improve the sustainability and resiliency of civil infrastructures around the world…Read More

Bayesian Filtering and Identification of Nonlinear Structural and Mechanical Systems

System identification is the process of using measurements of the response of a system to infer the parameters that define its mathematical models. The identification of parameterized model classes and model parameters has several applications in structural mechanics, including operational condition assessment and management, improvement of design methods, design of experiments, structural control, and structural reliability applications, among others. With the increase in the design of engineering systems that exploit nonlinear phenomena the identification of nonlinear systems has gained significant attention in recent years. In structural systems typical sources of nonlinearity include large displacements, large deformations, material nonlinearity, boundary conditions, energy dissipation devices for vibration suppression, actuators, among others. In this research Bayesian methods are developed for the estimation of the parameters that define the models of nonlinear systems, and in the estimation of their dynamic response from measurements at limited spatial locations…Read More

Uncertainty Quantification and Propagation in Nonlinear Structural Systems

Uncertainty is ubiquitous in the analysis and design of engineering systems. Sources of uncertainty in structural and mechanical systems include modeling errors (model class and/or parametric), measurement noise, unmeasured input excitations, and unknown initial conditions, among others. Probability theory provides a consistent, robust and rigorous theory that can be employed to model most of the sources of uncertainty observed in engineering systems. The quantified uncertainties can then be propagated to quantities of interest that are used for probabilistic condition assessment, robust performance prediction, risk analyses, and decision-making strategies under uncertainty. Research in this field has gained attention in recent years in part because of the increase in the computational resources available, especially parallel computing…Read More