The thesis presents an integrated numerical–experimental study aimed at the dynamic characterisation and validation of Finite Element Models (FEM) of a timber pedestrian bridge located in Ås, Norway, characterised by an unconventional structural geometry. The main objective of the work is to evaluate the influence of boundary conditions on the global dynamic response of the structure by comparing different numerical model configurations with the experimentally identified modal parameters. The FEM model of the bridge was developed in two different configurations with different constraint assumptions in order to identify limiting conditions such that the real bridge behaviour lies within these two bounds.