Efficient Seismic Design of 3D Asymmetric and Setback RC Frame Buildings for Drift and Strain Limitation

Abstract

This paper presents an analysis–redesign-type approach for the efficient seismic design of three-dimensional (3D) irregular RC frame structures for bidirectional ground motions. The designs obtained using the approach satisfy interstory drift and ductility limits while having the minimum total moment capacity of all seismic members. This leads to cost-efficient designs because the total amount of steel as well as the base shear and overturning moments are relatively low. While doing that, the approach is very intuitive and is relatively simple to implement in practice because it only requires analysis tools, not background knowledge or tools related to optimization theory. The examples show that the proposed methodology requires only a few analyses and converges to designs that exactly satisfy the design objectives with limited amounts of steel assigned only where required. This makes the design approach feasible for practice in terms of computational effort and time.