Seismic protection of timber platform frame building structures with hysteretic energy dissipators: feasibility study

Abstract

This paper describes a feasibility study of new hysteretic energy dissipators for seismic protection of timber platform frame buildings, either for retrofit or for new construction. The system consists in connecting the timber frame to a steel framed structure that includes the new energy dissipators devices, designed to absorb most of the seismic input energy thus protecting the timber frame and the other steel members; alternatively, the system might contain other dissipative devices. The steel structure comprises horizontal beam-like elements, vertical column like elements and chevron-like bracing members; the beam-like elements are steel belts embracing each slab of the building and the bracing members hold the energy dissipators. The steel structure is self-supporting, i.e. the timber frame is not affected by horizontal actions and can be designed without accounting for any seismic provision; in turn, the steel members do not participate in the main carrying-loads system. The timber-steel contact is even, smoothed and spread; it guarantees that the yielding of the dissipators is prior to any timber failure. This research belongs to a wider project aiming to promote the structural and constructional use of timber in seismic regions; this research includes experiments and advanced numerical simulation aiming to derive accurate design criteria. Comparison with unprotected buildings and other earthquake-resistant solutions is in progress.