Dynamic response of composite frames with rubber-based dissipating devices: experimental tests

Steel concrete composite frames can make up efficient earthquake resistant structural systems due to the formation of plastic hinges, even though they have to sustain a certain amount of damage that makes it hard and economically heavy to repair the structural members. As this kind of structures is usually characterized by little viscous damping and large lateral deformability, the idea is to apply some dissipating devices with the aim at both adding stiffness to the bare frame in order for the structural system to remain elastic at the damageability limit state and increasing damping at the ultimate state in order to minimize the structural damage. In this paper the authors report the results of a preliminary experimental campaign carried out on a real scale composite space frame equipped with a dissipating bracing system endowed by high damping natural rubber devices.