Dynamic buckling of end anchored floating bridges

Abstract

The Bjørnafjord bridge is a floating bridge planned to be a part of The Norwegian Public Roads Administrations ferry-free road project along E39. This thesis looks into the dynamic behavior of this bridge, focusing of dynamic buckling.

This thesis looks into three simplified versions of the bridge, a 5000 meters long column with a lumped mass, an arch with horizontal length of 4600 meters and a very simplified bridge model. All three models have been tested for linear buckling, nonlinear buckling and dynamic buckling.

In regards to dynamic buckling, analyses show that all three models have unstable areas around the natural frequency, resonance, and double the natural frequency, parametric resonance. For the arch model and the simplified bridge, analyses were also run with a stochastic loading. The results from these analyses show that parametric excitation might also occur by a random load.