الفهرس 
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Abstract
This work presents a numerical study to investigate the performance of enhanced extended end plate SMA bolted connections under cyclic loading. An elaborate FE model has been developed to be used in this study considering all the problem aspects; geometrical and material nonlinearities, the contact between attached parts, and the pretension in bolts. Auricchio’s model is used to simulate the super-elastic behavior of the SMA bolts. This FE model has been verified against the available published experimental results of several typical steel connections and results of tested SMA bolts, where good agreement has been achieved. Accordingly, the model has been applied to analyze the enhanced SMA bolted connections, through investigating two bolt systems. The first is the “SMA system” where all bolts are replaced with SMA bolts. The second system is the “DUAL system” where the extreme bolts only are replaced by SMA bolts. The results have been compared with those of typical steel connections where major improvement in minimizing the residual rotation, without losing great magnitude of the connection capacity has been achieved. A parametric study has been then conducted using the verified model. Connection capacity and residual rotation are of primary concern. Parameters considered are the SMA material properties (six parameters), and geometrical bolt parameters (bolt diameter, and bolt length). In order to build the numerous FE models needed for this study, semi auto technique has been proposed. In this research, an index “CI” which is capable to assess the two important inherent characteristics for the connection performance; the moment capacity and residual rotation, has been proposed. This “CI” is the ratio between relative residual rotation and relative moment capacity. The notation of relative value is the ratio between the value in the SMA case, and the corresponding value in the steel designed case. Results indicate that the SMA material property parameter (the starting of transformation during loading stress) and bolt diameter have significant impact, while bolt length has very small effect. Other material property parameters have no influence on the mentioned concerns. An equation of third degree has been derived to correlate relative residual rotation with relative moment capacity for the SMA enhanced connection, based on the present extensive parametric study. Moreover, charts have been developed to be used with the derived equation for the design of SMA parts (bolts) of the enhanced connection to achieve the needed relative residual rotation.