Hysteretic behaviour of dissipative bolted fuses for earthquake resistant steel frames

• A new fuse device for moment resistant steel frames was developed.
• The behaviour of these devices was studied through experimental tests.
• Fuses present good energy dissipation capabilities and are also easy to repair.
• The proposed design models show good agreement with experimental data.

One of the most recent trends in earthquake-resistant design of structures – damage control when these are subjected to severe earthquakes – led to the development of an innovative repairable fuse device for dissipative beam-to-column connections in moment resistant steel frames with composite beams. This fuse consists of a set of bolted steel plates, at the web and bottom flange, connecting the “I” beam profile stub to the beam element. The seismic performance of the proposed device was assessed through an extensive experimental campaign comprising twenty-four cyclic and two monotonic tests. Those tests were conducted on a set of three beam-to-column sub-assemblies with different fuse devices for each test. The tested devices varied in terms of selected geometric and mechanical parameters, such as the resistance capacity ratio and the geometric slenderness. The tests showed that the proposed devices were able to concentrate plasticity and to dissipate large amounts of energy through non-linear behaviour. Subsequently, two distinct design models are proposed to allow the computation of the resistance and stiffness of the fuses. The results of these design models were favourably compared with those from the experimental tests.