Fatigue assessment of the gusset-less connection using field data and numerical model

Abstract

Fatigue assessment of the novel structural components that are not explicitly addressed in the existing bridge design codes require the application of the local fatigue assessment methods. This study presents fatigue assessment of the novel gusset-less connection of the case-study vertical lift truss bridge, the Memorial Bridge, in Portsmouth, NH. The long-term structural health monitoring responses are collected from the instrumented gusset-less connection at the Memorial Bridge to determine the nominal fatigue response using the collected strain responses. In addition, a global multi-scale finite element model of the bridge is created to effectively model the structural components of the bridge. A local sub-structure finite element model of the connection is created to determine the stress concentration factors that are applied for the hot-spot fatigue assessment method. The acquired stress concentration factors under the static and dynamic load test are applied for hot-spot fatigue assessment of the gusset-less connection.