Seismic damage evaluation of ductile R/C beam and column: Part 1 Development of an analytical model for evaluation of crack length in R/C member

The final goal of this study is to develop an evaluation method of seismic damage in reinforced concrete structural members which is essential in accurate estimation of reparability limit state of R/C buildings damaged due to earthquakes. Firstly, general concept and outline of damage evaluation procedure of ductile R/C members were presented. Parti focused on proposal of an analytical model for crack length evaluation in ductile column and beam was developed. the analytical model of crack lengths consists of two parts; Models in and outside the plastic hinge regions which correspond to flexural spring and shear spring, respectively, for the frame analysis under and/or seismic loads. the proposed models calculated total crack length from the predicted number and average length of flexural and shear cracks. Finally, crack length evaluated by the proposed method was compared with authors' column and beam specimens and relatively good agreement was observed.