| In order to examine the effectiveness of the seismic retrofit for bridges through the experience of the 2011 Great East Japan Earthquake， authors report the seismic behavior of some retrofitted bridges during the earthquake with comparison of the damage of unretrofitted bridges， and summarize that the seismic retrofit for bridge columns has been effective to prevent vulnerable failure in columns. It should be also remarkable that the structural members attached with the additional shear keys or the unseating prevention devices were damaged in some retrofitted bridges. |
