Research On Bend-Shear-Shape Cu-SMA Damper

This thesis presents a study of mechanical property on a new type of Cu Shape Memory Alloy. Based on Muller model and Preisach model, a new mathematic constitutive relationship is set up for this SMA. Then, a SMA damper is designed by using pseudoelastic behavior of this SMA and the analysis of its dynamic property is carried out to evaluate its damping effectiveness experimently.First, the state-of-the-art researches of vibration control technologies on long-span spatial structures and the overview of SMA applications in structural vibration control are summarized. Then the experiment about mechanics property of CuZnAl SMA at the austenitic state is completed. A model is put forward to describe the characteristics of the reorientation among martensit evariants and the stress-induced martensite transformation microscopically. Moreover, it can describe the behaviors of the hysteresis and inner-hysteresis of the stress-strain macroscopically , it also can be used for engineering calculation.Based on above researches, a type of passive dissipation damper is proposed and its effective damping character is verified by the random vibration experiment under the excitation of white noise with limited band. Spectral analysis is adopted as the signal processing of the collected data to get energy transfer rate and acceleration transfer function. The damping effect is considered and its result shows this type of damper can decrease the vibration response effectively. Therefore this damper has an extensive application prospect.