Multilinear one-dimensional shape memory material model for use in structural engineering applications

In this paper a simple multilinear thermodynamics one-dimensional constitutive model for simulating the behavior of Shape Memory Alloys (SMAs) subjected to different types of loading conditions (low rate and high rate) and at different temperatures is presented. The main feature of this model is its simplicity while capturing some of common complex phenomena associated with SMAs. The ability of the proposed model to simulate high rate loading conditions especially for NiTi makes it suitable for implementation in seismic loadings. The dual detwinning and transformation mechanisms of SMAs can also be predicted by the proposed model. The multilinear nature of this model makes it appropriate for use in commercial nonlinear finite element software packages. Numerical simulations of the proposed model in comparison with other existing models and verification with experimental data are included.