During Kobe and Northridge earthquake, many steel buildings were found to have experienced brittle fractures at beam-to-column connections. After those earthquakes, various problems caused by welding material or welding process have been studied both in Japan and U.S. However, little study results have been utilized each other. This paper compares Japan with U.S. on the following three points. The first one is the properties of welding material used well in Japan and the U.S. The next one is the rationality of the combination of welding material and base metal to give beam-end fully plastic deformation. The last one is whether the above-mentioned welding material has enough toughness to apply its connection into Special Moment Frame.
