INERD pin and U connections

INERD pin and U connections were developed during the RFCS-supported INERD project [3-5]. The connections are composed of a steel pin or a U-shaped steel plate and connect the ends of braces in concentric braced frames (Fig. 1). INERD pins transfer brace axial forces through three-point bending, while U-plates bend and roll along the column face. The connections act as semi-rigid ductile dissipative brace connections. The connections are of partial strength in order to protect the braces from yielding and buckling, so that energy dissipation occurs exclusively within them and not in the braces. They can easily be replaced if damaged after a strong seismic event. The connections and the overall frames were experimentally/analytically/numerically studied at NTUA Athens, POLIMI Milano and IST Lisbon.