Residual seismic capacity evaluation of overall weak-beam RC frame based on energy absorption capacity

In this paper, residual seismic capacity ratio of overall frame, which means the reduction degree of seismic safety margin until the safety limitation of frame, is proposed for the weak-beam RC frame based on energy absorption capacity (exact calculation method). The feature sections, which assume the damage ranks such as slight, minor, moderate, severe and collapse, are then defined based on the engineering demand parameter. The relationship between residual seismic capacity ratio of overall frame and feature sections is also discussed to determine the threshold value of residual seismic capacity ratio of overall frame. The simplified calculation method for residual seismic capacity ratio of overall frame is furthermore proposed employing for the damage information, such as maximum residual crack width of members, obtained at on-site. The simplified calculation method for residual seismic capacity ratio of overall frame is finally applied to the previous test results of two weak-beam RC frames, and its feasibility is discussed. As a result, the damage ranks of 2SH-64 specimen are found similar to each other estimated based on the exact and simplified calculation melhod. The damage ranks of 1SF specimen are however overestimated by the simplified calculation method.