Analytical Response and Design of Buildings with Metallic Structural Fuses. I

Seismic design relies on inelastic deformations through hysteretic behavior. However, this translates into damage on structural elements, permanent system deformations following an earthquake, and possibly high cost for repairs. An alternative design approach, proposed in the past, is to concentrate damage on disposable and easy to repair structural elements (i.e., “structural fuses”), whereas the main structure is designed to remain elastic or with minor inelastic deformations. The implementation of the structural fuse concept into actual buildings would benefit from a systematic and simple design procedure. Such a general procedure is proposed here for designing new or retrofitted structures. The proposed structural fuse design procedure for multi-degree-of-freedom structures relies on results of a parametric study (presented in the paper), considering the behavior of nonlinear single degree of freedom systems subjected to synthetic ground motions. Nonlinear dynamic response is presented in dimensionless charts normalized with respect to key parameters. The proposed design procedure is illustrated as an example of application using Buckling-restrained braces as metallic structural fuses. This example is used in an experimental project (which is described in a companion paper) as a proof of concept to the developed design procedure.