In this paper the modal testing of a composite footbridge using an instrumented hammer is described. A finite element (FE) model for the structure was prepared and calibrated against the test results. This FE model was then employed to investigate the appropriateness of the pedestrian load model adopted in the British and Ontario codes of practice for the vibration serviceability limit state for this type of structure. The fundamental frequency of vibration of the structure was found to be within the range of the second harmonic of the walking load and thus attention was concentrated in this frequency range. The pedestrian load, as defined in the codes, was applied to the FE model and accelerations were calculated the amplitude of this load was expected to produce conservative estimates according to the latest research into modelling the walking load. A comparison between the results obtained from the calibrated FE model with test measurements on site revealed that the numerical calculations overestimated the results. Differences in shape between the time response signals of the two groups of results were also observed and are discussed.
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