Abstract
Since the number of excessive seismic loading cycles is observed to be less than ten, such very short term loading experiments are conducted to investigate the super - low - cycle fatigue behavior of steel pier base joint. Cracks are initiated in such an early stage as the second cycle at the inter section of a longitudinal corner weld between a column flange and a column web and a transverse fillet weld between a column flange and a base plate, and prop agated to fracture a flange plate rapidly after corner welds are broken. The crack initiation life can be evaluated by means of elasto - plastic finite element analysis, using a cyclic stress-strain curve.
