SHAKING TABLE TESTING OF AN RC FRAME WITH DISSIPATIVE BRACINGS

摘要

Dissipative Bracings (DB) have been used over the last decade, mostly in North America and Japan, for controlling the seismic response of framed buildings through the absorption of a portion of the input energy. However, most of these applications, as well as numerical and experimental research, concern steel structures. In Europe, on the contrary, the main interest in DB is for retrofit of RC-framed low-rise buildings designed according to non-seismic specifications or old seismic codes. These structures are more rigid than tall steel frames, and thus require DB able to dissipate energy at very small displacements. The research presented here is aimed at verifying experimentally the design methods used to optimise the location and characteristics of DB for installation in RC buildings, as well as evaluating the relative performance of three damping technologies, I.e. non-linear fluid viscous damping, elastomeric viscoelastic damping, and steel hysteretic damping. Shaking table tests are under way on two identical one-bay, 2 storey, full-scale spatial RC-frame structures, one bare and the other equipped with DB. The frames are designed to be representative of existing structures built before the introduction of recent seismic codes based on ductility requirements. The results will make an important contribution to the future extension of the European Building Code for seismic regions (EC8) to cover structures with auxiliary damping devices.