In this paper, the long-term crustal flow of the Iranian Plateau is computed using a kinematic finite-element model (NeoKinema software). Based on the iterated weighted least squares method, the models are fitted to the newest data set of Iran including updated fault traces, geologic fault offset rates, geodetic benchmark velocities, principal stress directions, and velocity boundary conditions. We are successful to find the best kinematic model, in which geological slip rates, geodetic velocities, and interpolated stress directions are fitted at levels of 0.35, 1.0, and 1.0 datum standard deviation, respectively. The best fitted model, for the first time, provides long-term fault slip rates, velocity, and anelastic strain rate field in the Iranian Plateau from all available kinematic data. In order to verify the model, the estimates of fault slip rates are compared to slip rates from merely analyzing geodetic benchmark velocities or paleoseismological studies or published geological rates which have not been used in the model. Our estimated rates are all in the range of geodetic rates and are even more consistent with geological rates than previous GPS-based estimates. Using the selected model, long-term average seismicity maps and long-term moment rates are produced on the basis of the SHIFT hypothesis and previous global calibrations. Our kinematic model also provides a new constraint on ratio of seismic deformation to total deformation for different seismic zones of Iran. The resulting slip rates and the proposed seismic fraction of deformation provide the necessary input data for future time-dependent hazard studies in Iran. Moreover, spatial distribution and total number of strong (M > 6) and major (M > 7) earthquakes, which dominate the seismic hazard, are all compatible with the regional seismic catalog.

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In this article, an innovative base isolation system based on steel–polytetrafluoroethylene sliding bearings equipped with shape memory alloy is proposed. This isolation system employs superelastic Ni–Ti alloy cables as recentering components and dissipates input energy through the friction and additional damping of shape memory alloy. As a case study, Izadkhast Bridge, the longest railway bridge in Iran, is considered and fitted with the proposed system. A three-dimensional nonlinear finite element model of the bridge is developed and time history analyses for various earthquake records are conducted. The results demonstrate that the proposed isolation system can effectively improve the bridge response quantities. Moreover, equipping the sliding bearings with shape memory alloy efficiently reduces permanent deck displacement of the base-isolated bridge. This study reveals that shape memory alloy cables mostly work as recentering elements with regard to the minimal damping capacity of shape memory alloy cables. In addition, sensitivity analyses on environmental temperature reveals that mechanical behavior of shape memory alloy on minimum probable temperature should be considered in design procedure. Regarding the financial and functional aspects, using minimum cross-sectional area and length of shape memory alloy cables is appropriate. Moreover, the geometric characteristics of shape memory alloy cables should be selected, so that shape memory alloy strain is being limited to the recoverable range (up to 8%).