Experimental characterization and mechanical modeling of additively manufactured TPU components of innovative seismic isolators

This work presents an experimental and mechanical study on the tensile response of 3D-printed thermoplastic polyurethane membranes, to be used as stretchable members of novel seismic isolators. The examined specimens have been 3D-printed by fused deposition modeling at the Rapid Prototyping Laboratory of the University of Salerno. Cyclic tests performed at different strain rates are employed to characterize the mechanical response of such members and the dependence of preconditioning effects on the recovery time and the initial pretension of the specimens. The presented results show a marked hysteretic response, the fast recovery of residual strains with time, and an appreciable increase of the tangent tensile modulus along the loading phase of the stress–strain curve with growing values of the applied strain rate.