Pipe dampers as passive devices for seismic control of isolated bridges

摘要

During an earthquake, pounding of bridge superstructure into abutments is potentially destructive to structural elements and may cause unseating failure and collapse. By using energy dissipative devices such as passive dampers, the harmful pounding force may be prevented. One of the most economical passive dampers for structural applications is the pipe damper, recently introduced by the authors. In this paper, computer models of a two-span 60-m long conventional overpass bridge are equipped with different lengths of two types of pipe dampers, namely the dual-pipe (DPD) and infilled-pipe (IPD) dampers. A simplified lumped-mass model for the bridge considering soil stiffness is proposed and used in the study. A connection detail for connecting pipe dampers to the plate girders is also presented. The detail ensures that pipe dampers act only in the longitudinal direction, and no moment is transferred to the girders. A parametric study is performed on pipe damper length and excitation peak acceleration. Seismic responses of the bridge model with and without pipe dampers are investigated. The results of the study prove that both types of pipe dampers are effective in eliminating pounding force and significantly reducing seismic responses of bridges at a very low cost. A simple displacement-based procedure for design of dual-pipe damper and infilled-pipe damper elements to prevent deck-abutment impact in bridges with expansion joints is suggested in this study. An example of the suggested design procedure is then presented. The design example demonstrates an acceptable correspondence with the results obtained from the parametric analysis. Copyright (C) 2016 John Wiley & Sons, Ltd.