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

Abstract

The chapter discusses dynamic responses of composite frames with rubber-based dissipating devices. The chapter analyzes composite moment-resisting space frames where lateral stiffness and equivalent viscous damping are augmented by means of dissipating devices, and presents 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. Moment-resisting frames made of steel-concrete members provide an efficient earthquake resistant system. The efficiency is entrusted to the formation of plastic hinges located at the ends of the beams or at the beam-to-column joints designed as partial strength connections. This design criterion is satisfactory in preventing the structure from collapse against high intensity earthquakes, but it often leads to a very large lateral deformability which brings on excessive inter-storey drift under low intensity earthquakes. The energy dissipation associated with the ductile behavior of dissipating zones induces a large amount of structural damage which usually calls for very expensive and difficult rehabilitation works.