Finite element modelling of detachable short links

Abstract

Eccentrically braced frames with replaceable links are viable seismic resisting systems that guarantee large dissipative capacity and quick and easy replacement of the damaged dissipative zones after seismic events, thus reducing the repair costs. Experimental tests carried out within DUAREM research project [12] demonstrated the high effectiveness of this system and highlighted the importance of the bolted connections of the shear links on the system response at both global and local level. In order to investigate the behaviour of the tested detachable links, finite element analyses have been carried out. The finite element (FE) models are calibrated on the basis of the experimental response curves in terms of the shear force and link rotation. Once calibrated the finite element models, several parameters have been investigated such as the type of pre-loadable bolts (i.e. HR and HV), the level of bolt clamping force, the boundary conditions, the presence of constructional tolerances (e.g. initial gap between end-plate at both link ends). The results from the parametric study enables the characterization of the shear and axial force interaction on the link end connections.