GNGTS 2017 - 36° Convegno Nazionale

446 GNGTS 2017 S essione 2.3 UGCWs, both in global and local terms. As far as K d increases, c d further increases, see Eqs. (1) and (2). However, limited sliding only can occur in VE devices, with minimum damping contribution and hence benefits for the structural components. Based on Fig. 3d, an optimal balance of local and global performances for the examined case study was found to lie in the range of R K ≈3-4 values. In global terms (see Fig. 3e), markedly reduced top displacements of the 3D frame were noticed, in presence of VE connectors. At the local level - for properly designed VE devices - maximum stresses in the UGCW components can be also highly minimized. Even the imposed seismic records were found to do not lead glass panes to failure, the R K =4 configuration lead up to ≈-50% the stresses of the traditionally restrained UGCW. In addition, the flexibility of UGCW supports proved to beneficially affect the distribution of stresses in glass panels. Local peaks of stresses close to the glass supports and edges were in fact generally avoided, due to VE fasteners, see Fig. 3f, with obvious benefits for the overall dynamic performance of the full structural system. These global and local findings derive from the combined flexibility Fig. 3 - Dynamic performance the 3D building with dissipative UGCWs (ABAQUS): a) fundamental mode and b) variation of vibration periods with RK; c) records for nonlinear dynamic seismic analyses, with d) measured drifts, e) maximum stresses in glass and f) related distribution (legend values in Pa).