Beam based finite element modelling of Herøysund bridge

Abstract

In this thesis the candidate aims to model two finite elements models of the post tensioned concrete Herøysund bridge. First a solid element model is modelled using the documentation from the bridge construction, then a beam element model is modelled using the solid model as a foundation. These models are subjected to a structural analysis that applies boundary conditions, joints, mass, gravity, asphalt, railings, and the post tensioning system. Then the structural analysis is used as a pre-stress condition for a modal analysis on each model. The modal analysis is used to find the eigenfrequencies and corresponding mode shapes of the bridge models. Interesting results from both models’ analyses is compared to reveal how similar the models are and which model gives the most reliable results. The modes are compared using the modal assurance criterion. The modes are then evaluated, and significant modes are suggested for comparison with operational modes that will be extracted from the bridge in the future.