TWO CASE STUDIES IN THE USE OF TUNED VIBRATION ABSORBERS ON FOOT BRIDGES

Abstract

The work described is part of a research programme into ways of reducing pedestrian-induced vibrations of footbridges, the problem being that these vibrations can cause discomfort to the user. The two case studies presented describe one method by which this has been achieved - the discrete tuned vibration absorber. Results show that an absorber with a low mass value (approximately 0.6% of the bridge superstructure mass) can achieve very worthwhile reductions in vibration levels. This effect is, however, dependent on optimum damping and accurate tuning of the absorber and on minimum dry friction in the absorber movement.(a) (TRRL)