SEISMIC PERFORMANCE OF FLARED BRIDGE COLUMNS

This report describes a joint analytical and experimental research program which investigated the influence that flares have on the structural behavior of columns. The program also verified the potential seismic performance issues associated with flared columns. Ten model columns were constructed and tested in two phases, upside down, as simple cantilevers. The columns featured both large and heavily reinforced structural flares or small, light reinforced, non- structural flares. A prismatic reference column, as-built/as-designed column, and retrofit/improved flare designs were tested for both phases. Practical solutions for analyzing, design, and retrofitting flared columns are proposed, based on this research.