Outer girder of girder end parts, consisting of main I -girders, stiffeners above the supports, crossbeams and so on, in steel girder bridge had serious damages by lateral load during a strong earthquake. However, design method of the girder ends, having reinforcing steel members, against the lateral load is not detailed in design specifications. Experimental observations of a web gap, a clearance between the underside of the crossbeams and the lower flange plates of the main girders, will help to discuss that point, but a few experimental studies were carried out. Then in this paper, loading tests using partial scaled models of the outer girder end are carried out to reveal load carrying capacity against the lateral load .
