Resiliency of steel and composite structures

This paper is divided into two parts. The first part addresses the resiliency and sustainability of steel and composite structures from a fundamental standpoint, and it is intended as an introduction to the other six papers that form part of this issue related to resiliency of steel structural systems in seismic areas. The paper posits the idea that resiliency is a characteristic that embodies sustainability rather than the traditional opposite point of view. The second part of the paper is divided into two sections, with the first section describing a number of retrofit technologies with recentering characteristics that have been developed for small, seismically deficient buildings in developing countries. The second section describes an innovative connection between circular concrete filled tubes and conventional beams with reduced flange sections consisting of steel and shape memory alloy bars and end plates. The connection has partial restraint behavior and strong recentering properties. This connection is used to demonstrate that some creative thinking can lead to innovative ways of addressing issues related to robustness, resiliency and sustainability of steel structures.