NEW HOLISTIC STRUCTURAL ROBUSTNESS AND STRUCTURAL REDUNDANCY INDICES FOR TRUSS BRIDGES: FORMULATION AND PRACTICAL APPLICATIONS

Abstract

The objectives of this thesis are to 1) formulate a new holistic structural robustness index for truss bridges, along with a separate index for structural redundancy, 2) apply the new indices to assess a steel truss bridge against corrosion damage showcasing their value within a new asset management framework, and 3) develop a novel optimization framework to maximize robustness and redundancy while minimizing the volume of material required for upgrade. In short, the new indices are the recommended option for practicing structural engineers, and the new asset management framework allows owners to target critical bridges for repair or replacement given budgetary constraints. Furthermore, the optimization framework strategically upgrades the first element failure in the collapse simulation, and its utility is tested on another truss bridge subjected to corrosion damage offering an upgrade that is more robust and redundant than a repair achieved per CSA S6:19.