Experimental Investigation of the Structural Fuse Concept

Keywords: Passive energy devices (PED).  Structural performance.  Seismic damage.  Metallic dampers.  Structural fuses (SF).  Elasticity.  Seismic performance.  Retrofitting.  Buckling-restrained braces (BRB).  Triangular added damping and stiffness (T-ADAS).  Shear panels (SP).  Single degree of freedom (SDOF) systems.  Multidegree of freedom (MDOF) systems.  Floor demands velocities.  Accelerations.  Nonstructural damage.  Shaking table tests.  Moment-resisting connections.  Seismic isolation.  Ball-in-cone (BNC) system.  Pin connections.

Abstract: In a previous report (Vargas and Bruneau, 2006) a procedure to design structural fuse systems was presented.  As a proof of concept to the developed design procedure, an experimental project which consisted of a three-story frame designed with BRBs, was conducted on the shaking table at the University at Buffalo.  Two types of BRBs with different types of connections were used in this test:  moment-resisting connections and pin connections, manufactured by Nippon Steel Corporation (Japan) and Star Seismic (USA) respectively.  This experimental project also assesses the replaceability of BRBs designed as sacrificeable and easy-to-repair members. Design and behavior of this type of connection is investigated, as is the use of seismic isolation devices to protect nonstructural components from severe floor vibrations in buildings designed per the structural fuse concept.  Tables, illustrations, and references are included.