Development and Mechanical Characterization of a Novel Ni-Ti Based Damping Seismic Device

Traditional seismic devices suffer from residual deformation issues that compromise structural resilience and require extensive post-earthquake repairs. An innovative seismic self-centering device based on Ni-Ti shape memory elements for enhanced structural performance and damping is presented in this work. The investigation encompasses both L-shaped sheet and helical spring configurations tested under quasi-static conditions, with individual component characterization across two temperature conditions (25°C and 100°C), followed by comprehensive evaluation of assembly configurations including Ni-Ti sheets, steel baseline comparison, and combined Ni-Ti sheet-spring systems. Experimental results demonstrate distinct performance trade-offs among SMA configurations. Combined Ni-Ti sheet-spring assemblies optimize self-centering capability (99.5% recovery) with highest force capacity (224.5N) but reduced energy dissipation (8.1 x 104J/m3), while individual L-shaped Ni-Ti sheet configurations provide balanced performance across all metrics, showing promising characteristics in terms of load, displacement and energy dissipation. Temperature analysis revealed substantial force enhancement of +121% from 25°C to 100°C at 2.5mm displacement, establishing thermal control as a design parameter. At 25°C, L-shaped configurations achieve forces of 40.9-206.8N with energy dissipation of 8.1 x 103 - 1.89 x 105J/m3, while elevated temperature testing demonstrates enhanced force capacity up to 405N with increased energy dissipation up to 2.82 x 105J/m3. The experimental results demonstrate that the proposed SMA sheet configurations exhibit reliable energy dissipation characteristics, maintaining consistent self-centering capabilities across the tested temperature and load range. These findings establish experimental foundation for future dynamic validation studies and contribute to the advancement of SMA-based damping systems for structural seismic protection.