Performance-based efficient seismic design of reinforced concrete frames with vertical irregularities

Distribution pattern for the equivalent static lateral force in the seismic design process appears to be based on elastic approach. On the contrary, during extreme events such as seismic load, structures experience inelastic range. Consequently, the assumed lateral load distribution pattern for the seismic design does not remain applicable in the inelastic range. Thereby, some members of the structure go through extreme stress/deformations and the other experiences minor stresses/deformation. Current paper presents near optimum (i.e., efficient) design of reinforced concrete (RC) frames with structural irregularities applied to seismic excitations based on the model of uniform distribution of deformation and thereby damage. The efficient design is achieved by moving the material (i.e., steel reinforcement) from the members with minor deformation/damage to the member with extreme deformation/damage. The efficient design procedure for multiple performance objectives is demonstrated through the examples of irregular frames. The study illustrates that for same damage, efficient design requires less material (i.e., steel) than the design based on practicing code; again for the same amount of material (i.e. steel), efficient design gives less structural damage compared to the design based on practicing code. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.