## 7 Conclusions  
For nearly two decades, researchers have been using SMA wires in conjunction with isolators of the bridges to control their displacements and residual deformations. Different configurations of the SMA wires around the LRB isolators have been reported, namely, double-cross, straight, and cross. In this paper, the performance of these three SMA-LRBs is compared by implementing them in the LRBs of a benchmark highway bridge. Each configuration leads to specific characteristics of the SMA-LRBs and thus specific shear hysteresis. In addition to the wire's arrangements, LRB dimensions and the radius of the wire are also influential parameters in the SMA-LRB behavior. For a specified LRB dimension, by increasing the radius of the wire, the horizontal stiffness, and consequently, the base shear and deck acceleration of the bridge rise, but the maximum and residual displacement reduce. To get the best performance out of SMA wires, a multi-objective non-dominated sorting genetic algorithm (NSGA-II) is applied to find the radius of the SMA wire for each configuration that simultaneously minimizes the deck acceleration and mid-span displacement. After optimizing the isolators, to evaluate and compare their performance, nonlinear dynamic analysis is conducted for the five distinctive states of the benchmark bridge, i.e., non-isolated, LRB isolated, and the three SMA-LRB isolated bridges. For the nonlinear response history analysis, researchers can select ground motions from past recorded earthquakes in places other than the bridge's site and modify them to match desired conditions. However, because of the deficiencies of this practice, in this paper, strong ground motion records are selected in a way to fit the site conditions, and also ten synthetic spectrum-compatible and energy-compatible ground acceleration time histories are generated to be used in the analysis. The summarized results are as follows. * As for the optimized double-cross SMA-LRB, this device decreases the maximum base shear and deck acceleration of the isolated bridge from 70.29% to 87.85% and from 20.89% to 62.57%, respectively, under various records compared with the non-isolated bridge. However, LRB still leads to the largest reduction in these figures, from 77.71% to 91.07%, and from 56.85% to 82.66% under various records. Moreover, SMA-LRBs with double-cross wires reduce the maximum mid-span and residual displacements in ranges between 39.51% and 81.23% and from 52.16% to 98.67%, in turn, under different ground motions compared with the LRB isolated bridge. In brief, amongst the three SMA-LRBs, it has the largest shear force and deck acceleration, and needs the longest SMA wire, but leads to the least maximum and residual displacements. Finally, the result of the WSM method indicates that DC-SMA-LRB is the second most successful device. * Regarding the optimized straight SMA-LRB, it decreases the maximum base shear and deck acceleration of the isolated bridge slightly more than the double-cross SMA-LRBs, from 72.50% to 88.28% and from 26.76% to 66.90%, respectively, under different records, compared with the non-isolated benchmark bridge. Besides, SMA-LRBs with straight wires reduce the maximum and residual mid-span displacement slightly less than the DC-SMA-LRBs, from 37.06% to 80.00% and from 51.55% to 94.67%, in turn, under various excitations, compared with the LRBs. Moreover, the required length of the SMA wire is the least for this configuration. Lastly, the WSM method shows that S-SMA-LRB has the best overall performance. * As regards the optimized cross SMA-LRB, it results in the reduction of the base shear and deck acceleration more than the other two SMA isolators, compared with the non-isolated bridge. However, it decreases the maximum and residual displacements less than the others and uses rather long SMA wires. Eventually, by conducting WSM, it is ranked as the least successful device. In this research, the bridge model presented by [PERSON] et al.