Evaluation of Damage Distribution in Elements of Dual Frames

During severe earthquakes,many structures yield and experience large inelastic deformations. design procedure in current seismic design codes,is based on elastic behavior of structures and considers inelastic deformations implicitly. this fact results in inadequacy of current design practice as researches show. taking into account inelastic behavior of structural elements may better predict seismic responses. in the present study,three steel structures with dual system consisting of intermediate moment-resisting and concentric-braced frames that are widely used in medium and high-rise buildings,have been designed based on allowable stress design method. then,inelastic seismic responses have been determined under three earthquake records by the perform 3d software and hysteretic energy and damage state of structural elements have been evaluated in detail. finally,by column strengthening,it has been tried to reduce structural damages. the results indicate that this approach is an efficient technique to make the damage distribution uniform among structural members.