Cyclic tensile of refurbish NiTi reinforcement bar for seismic mitigation

摘要

This research highlighting the novel properties of pseudo-elastic Ni-Ti bar owing to their ability to reverse macroscopically inelastic deformation during earthquake known as recentermg capability and large elastic strain capacity.which originated from the reversible aus enite to martensite phase transformation.Hence,this paper presented and evaluates the cyclic properties of pseudo elastic Ni-Ti shape memory alloys to assess their prospective use tor seismic applications to be exploited as seismic resistant design and retrofit.In addition the correlation of hysteretic behavior of Ni-Ti alloy in terms of cyclic loading number and history mechanical properties at ambient temperature,equivalent damping,energy dissipation and recovery stress were evaluate.The NiTi bar with weight percentage of Ti-43 98 at % Ni 56 02 and diameter of 8 mm.The tensile cychc test obtained demonstrated a rounded loading curve based on a 0.2% offset.The as received bar exhibited superior pseudo-elastic behaviour and recentermg through repeated cycling without significant degradation or permanent deformation but low energy dissipation due to narrow hysteresis while the steel rebar shows vice versa bxperimental results show potential for the use of SMAs in seismic applications and provide areas tor continued research.It was conclude that the as-received pseudo elastic Ni-Ti bar is suitable use for seismic mitigation despite of their ability to undergo cyclical strains is 6% which is greater than 5%,with minimal residual strain,0.15% which is less than 1%