Iron-based Shape Memory Alloys Research Articles

Comparative Analysis of Concentrically Braced Frames with FeSMA and Steel BRBs Under Long-Duration Earthquakes

ABSTRACT Owing to high fatigue life, the iron-based shape memory alloy (FeSMA) buckling-restrained braces (BRBs) are emerging as a promising candidate against long-duration earthquakes. However, the corresponding analysis cannot be found. Current emphasis is paid on unveiling the seismic response differences between concentrically braced frames (CBFs) with FeSMA and steel BRBs when they are attacked by long-duration earthquakes. To directly assess the effect of earthquake duration, this paper selects a total of 90 pairs of short- and long-duration earthquake records, which are record-to-record spectrally equivalent over a wide range of fundamental periods, for nonlinear time history analysis. A benchmark six-story CBF is selected for demonstration purposes. In the numerical simulation process, the fatigue-induced damage is particularly considered. A preliminary examination is first conducted in the case study, in which a representative pair of short- and long-duration records is selected. In what followed, the statistical results from the ground motion suites are analyzed. This work not only highlights the higher failure risk of steel BRBs than FeSMA BRBs under long-duration earthquakes associated with maximum considered earthquake hazard level, but also confirms the advantages of FeSMA BRBs over steel BRBs in controlling residual deformations.

Material characterization of iron-based shape memory alloys for use in self-centering columns

Abstract Iron-based shape memory alloys (FeSMA) are emerging as promising materials for use in post-tensioning concrete structures to provide self-centering capabilities during a seismic event. Past experimental studies on FeSMA focused on strengthening or repairing existing structural components. In addition to the structural rehabilitation for gravity loading, FeSMA also have potential for use in self-centering columns subjected to seismic loads. However, the basic material properties, such as strength, ductility, recovery strain, actuation stress (i.e., prestress) stability, low-cycle fatigue resistance, and temperature dependence of FeSMA related to self-centering column applications have not been studied so far. To fill this knowledge gap and determine the feasibility of using FeSMA in self-centering columns, this study performed a comprehensive characterization and analysis of FeSMA both before and after actuation (i.e., thermal stimulation). The strength, ductility, and recovery strain of FeSMA before actuation were tested at different temperatures from -40℃ to 50℃. After actuation, the actuation stress, low-cycle fatigue resistance, and strain capacity of FeSMA were tested at different temperatures from -40℃ to 50℃, prestrain levels from 4% to 30%, and under low-cycle fatigue loading with strain amplitudes from 0.5% to 1.0%. The results from this study demonstrated that FeSMA exhibit high ductility, cyclic actuation stress stability, and low-cycle fatigue resistance at temperatures from -40℃ to 50℃. Furthermore, it was found that increasing the prestrain level can effectively increase the post-actuation strain amplitude at which the actuation stress reduces to zero. A prestrain level between 15% and 20% is recommended for application of FeSMA in self-centering columns. The research findings from this study demonstrated the feasibility of using FeSMA in self-centering columns subject to seismic loading.

Post-fire performance of iron-based shape memory alloy: Experimental study, prediction equations and constitutive models

To expand the application of iron-based shape memory alloy (Fe-SMA) for fire resilience improvement, this paper presents a systematic investigation on the mechanical properties of post-fire Fe-SMA. In tests, the specimens of China-made Fe-SMA were heated to target temperatures up to 1000 ℃, then cooled to room temperature in air or water, and finally subjected to tensile tests. The variation trends of mechanical properties with different cooling methods were analyzed, accompanied by the residual factor comparison with high strength steels Q460, S460, A36, A572 and A992, as well as with austenite stainless steel S30408. Finally, the prediction equations of residual factors and the post-fire constitutive model of Fe-SMA were proposed. Experimental results indicate that the exposed elevated temperature and cooling method significantly influence the post-fire performance of Fe-SMA. Compared with commonly used high strength steel and austenite stainless steel in civil engineering, Fe-SMA has unique post-fire performance, with a noticeable enhancement after exposure to elevated temperatures below 800 ℃. Therefore, the targeted theoretical prediction of post-fire Fe-SMA performance is significant and can be used as the investigation foundation for the fire resilience improvement application of Fe-SMA in civil engineering.

Measuring traction-separation relationships of bonded Fe-SMA double cantilever beam joints

Adhesively bonded strengthening systems using self-prestressing iron-based shape memory alloys (Fe-SMA) have demonstrated significant potential. However, the premature nonlinear behavior of Fe-SMA during debonding failure presents challenges in ensuring the integrity of the adhesive joint. A recent study indicated that this behavior may lead to premature joint failure, and a similar conclusion can be drawn concerning plasticity in thin adherends. To characterize the failure process of Fe-SMA bonded joints, a method capable of measuring traction-separation relationships of thin adherends bonded with tough adhesives is essential. An algorithmic method, supported by an analytical nonlinear beam-on-foundation model and a minimization scheme, is shown to offer a solution. To benchmark the method against the J-integral approach, experiments are conducted using two types of adherends: thick steel with thickness-limiting plasticity and Fe-SMA with material behavior that inevitably leads to nonlinear deformation. Comparison of methods shows both measurement method are valid and allow for proper predictive modelling using the finite element method. The proposed method can be readily employed to characterize various thin adherends with elasto-plastic material behavior.

The effect of γ′-martensite on the corrosion resistance of an Fe-Mn-Al-Ni-Cr shape memory alloy in a sodium chloride solution

The martensitic phase transformation in iron-based shape memory alloys has a strong influence on the corrosion properties. To investigate the effect of different amounts of martensite, potentiodynamic polarization measurements were conducted on specimens that were subjected to varying prestrain levels prior to the corrosion experiments. While the passive behavior deteriorates with an increasing martensite amount, the observed corrosion damage changes as well. While an entirely austenitic specimen is characterized by a predominantly surface corrosion with some randomly distributed pitting corrosion, the introduction of the martensitic phase results in micropitting and selective corrosion of the martensite plates.

Effect of Heat Treatments on Microstructure and Mechanical Properties of Fe-Mn-Ni-Al-Gd Shape Memory Alloy

There are significant scientific and industrial efforts to develop and optimize Iron-based shape memory alloys (SMA) such as FeMnNiAl for cost-sensitive applications. This alloy system shows shape memory and superelastic properties across a large temperature range. However, many studies have pointed out the need for rather complex thermo-mechanical treatments for the optimization of the SMA properties. In addition, works considering the effects of alloying on the development of microstructures that are more conducive to pseudo-elasticity in this system remain limited. Hence, systematic studies aiming at the investigation of the microstructural evolution of the FeMnNiAl(Gd) system are of great interest. In this study, solution heat treatment is done to tune the microstructure for optimum mechanical properties. The effect of phase distribution on mechanical properties is investigated at different heat treatments. Whereas cyclic heat treatment induced abnormal grain growth (AGG) in all samples, so large grains were obtained. The phase variation and elemental composition are analyzed by X-ray diffraction and Energy Dispersive Spectroscopy, respectively. The microstructure and phase distribution are observed using Scanning Electron Microscope and then related to the microhardness results. The microstructure has a good correlation with mechanical properties where the fine distribution of phases results in a higher hardness number.

Experimental and theoretical study on mechanical performance of Fe-SMA/steel single lap joints

The activated iron-based shape memory alloy (Fe-SMA) can introduce considerable prestress in the damaged zone of deteriorated steel structures through bonding technologies. In China, it has been successfully applied to several kilometer-span steel bridges, such as Sutong Bridge and Hangzhou Bay Bridge. The shear and interfacial performance of steel-to-Fe-SMA plates are crucial issues in bonding Fe-SMA to reinforce deteriorated steel structures, which remain unclear. This paper investigates the shear characteristics of Fe-SMA/steel single lap joints (SLJs), considering the effects of adhesive types, adhesive layer thicknesses and overlap lengths. The stress distribution and the interfacial shear stress at the overlap zone are obtained through experiments, and the damage evolution and load-transfer mechanisms of adhesive layers are analyzed. The experimental outcomes indicate that the maximum tensile stresses of Fe-SMA plates can reach 61 % of their ultimate strength. The failure modes and ultimate load of Fe-SMA/steel SLJs are affected by adhesive types. Interface failure occurs in CH 120 and PCMdur™-15 specimens, whereas interface, cohesive and mixing failure are formed in Sika 31 specimens. Due to the adverse effects of adhesive layer defects, out-of-plane bending moment, and damage accumulation of the adhesive layers, the distribution of surface strain and interfacial shear stress of all specimens are mainly at the effective overlap zone. For an efficient engineering design, the linear and polynomial fitting models of cohesive zone models with different adhesive types and adhesive layer thicknesses are proposed based on experiments. The experimental and theoretical achievements can provide design recommendations for deteriorated steel structures rehabilitated by bonding Fe-SMA.

Bonded and prestressed fatigue crack retarders based on Fe-SMA

A bonded and prestressed retarder concept is proposed in this work. The shape memory effect of an iron-based shape memory alloy (Fe-SMA) has been exploited to realize a desirable self-prestressing mechanism, resulting in compressive stresses in the parent structure. The synergistic prestressing and added fail-safe features of bonded and prestressed Fe-SMA retarders desirably restrain the fatigue crack growth. The fatigue crack growth behaviour in metallic plates reinforced with bonded and prestressed retarders is experimentally studied in this work. A test campaign has been implemented to investigate the effects of prestressing, as well as the influence of the relative location between the Fe-SMA retarders and the initial crack tip on the crack growth behaviour and fatigue crack life extension. The experimental results show that the prestressing of retarders desirably extends the fatigue crack growth life. More extension in fatigue life can be achieved by positioning the bonded prestressed retarders from 40 to 20 mm before the initial crack tip, the desirable retardation due to beneficial compressive prestressing and added load path on the small crack is significant. The findings in this work imply that it is beneficial to proactively reinforce the fatigue-prone locations in metallic structures with bonded and prestressed Fe-SMA retarders in order to extend the service life.

Experimental study on flexural performance of prestressed concrete beams strengthened by Fe-SMA plates

Shape memory alloy (SMA) is an innovative intelligent material, capable of restoring its shape before deformation upon reaching the critical activation temperature. This property promotes its promising applications in civil engineering. This paper proposes a novel reinforcement method and aims to investigate the reinforcing effect of iron-based shape memory alloy (Fe-SMA) plates on prestressed concrete (PC) beams through four-point bending tests on one reference beam without reinforcement and three Fe-SMA reinforced beams, as well as with three beams reinforced by carbon fiber-reinforced polymer (CFRP). The results show that Fe-SMA can effectively reduce concrete cracks, and improve stiffness and characteristic loads of beams without negative effects. Under the same loading conditions, new cracks of Fe-SMA reinforced beams were relatively fewer than those of CFRP reinforced beams. Besides, Fe-SMA exhibited superior performance when utilizing the same cross-sectional reinforcement material to enhance the bending capacity of beam, and proved more advantageous for improving stiffness and characteristic loads of beam under the identical initial tensile force. Furthermore, the reinforcing effectiveness of Fe-SMA positively correlates with the cross-sectional area (thickness) and recovery stress (pre-stretch level and activation temperature) of Fe-SMA. Increasing the thickness of Fe-SMA plates by 100%, while maintaining other parameters constant, resulted in a 33% increase in cracking load. Similarly, elevating the recovery stress from 314 MPa to 340 MPa led to a 12.5% rise in cracking load. This paper investigates the reinforcement effect of Fe-SMA plates on PC beams, and provides a reference for the application of Fe-SMA in PC beam reinforcement, laying a foundation for promoting the utilization of Fe-SMA in civil engineering.

Study on the flexural properties of T-shaped concrete beams reinforced with iron-based shape memory alloy rebar

Iron-based shape memory alloys (Fe-SMAs), which are emerging as a novel class of self-prestressing materials dispensed with in situ tensioning, have been studied primarily in the field of structural strengthening. In addition, the self-prestressing characteristics of the Fe-SMA rebars are extremely promising for new concrete bridges that are seriously affected by prestress loss during their service life. Therefore, the effect of self-prestress generated by embedded Fe-SMA rebar was experimentally investigated by six concrete T-beam. The influence of factors such as the activation status, prestress value, and diameter of the Fe-SMA rebar on the flexural performance was investigated. The variation laws of the cracking load, yield load, ultimate load, and stiffness were analyzed. The results illustrated that the activation of the Fe-SMA rebar had a remarkable influence on delaying beam cracking. Under the same load (130 kN), the specimens with an activated Fe-SMA rebar exhibited a remarkable reduction exceed 30% in crack width compared to those with an unactivated Fe-SMA rebar. Following the activation, the cracking load, yield load, ultimate load, and stiffness increased to varying extents,. The Fe-SMA, characterized by its remarkable ductility, exerted a beneficial influence on the deformation capability of the beams. This enhancement became notably conspicuous following Fe-SMA activation. Analysis of the cracking load and concrete strain during the activation process indicated that the prestress of the embedded Fe-SMA rebar closely approximated the values observed in the rigid confinement. The calculated flexural capacity agreed with the experimental data, and the proposed calculation method can provide a reference for subsequent research.

Constitutive model and activation recovery performance of Fe-SMA: Experimental and theoretical study

In this study, the static tensile properties, activation recovery properties, and post-activation static tensile properties of the China-made iron-based shape memory alloys (Fe-SMA) were experimentally studied and theoretically analyzed. The material parameters of the Ramberg-Osgood curve are modified based on the static tensile tests of Fe-SMA plates, leading to the proposal of a static tensile constitutive model suitable for Fe-SMA. The applicability analysis of the theoretical model indicates that the calculated curve achieves an accuracy of R2 ≥ 0.9. Subsequent activation tests revealed a locally optimal combination of pre-strain and activation temperature, which is concluded to be associated with the martensite content. Hot-rolled Fe-SMA plates demonstrate local maximum utilization when subjected to a 4% pre-strain and an activation temperature of 300 °C, resulting in a recovery stress of 314 MPa. Moreover, it has been determined that the two activation modes, namely single heating and multiple-cyclic heating, do not significantly impact the final recovery stress of hot-rolled Fe-SMA plates. Therefore, the multiple-cyclic activation of Fe-SMA can be utilized to compensate for prestress loss in practical applications. Furthermore, a comprehensive constitutive model for Fe-SMA is proposed based on the results of the post-activation static tensile tests. This model provides an accurate description of the static-tensile stress-strain relationship of Fe-SMA during pre-straining and after activation. This study focuses on investigating the constitutive relationship and activation recovery performance of Fe-SMA, providing an experimental basis, data support, and theoretical analysis for the practical application and further analysis of Fe-SMA in structural reinforcements.

Theoretical investigation and design recommendations for the initial stiffness of Fe-SMA/steel bolted joints in shear

Due to the self-stressing performance and easy-to-install, iron-based shape memory alloy (Fe-SMA) has been successfully applied to the prestressed rehabilitation of deteriorated long-span steel bridges, through bolt anchoring joints. The initial stiffness of Fe-SMA/steel bolted joints affects the transfer and distribution of external load and initial preload, which is significant in investigating the mechanical behavior of Fe-SMA plates for structural reinforcements. However, the current leading design standards for the bolted joints are based on mild steels, whose reliability requires investigation when employing Fe-SMA. For this purpose, the applicability of EN 1993-1-8 in predicting the initial stiffness of Fe-SMA/steel bolted joints is evaluated by experimental and numerical results. A parameter study exploring the influencing parameters of Fe-SMA plate thickness as well as end and edge distances on the initial stiffness of Fe-SMA/steel bolted joints is conducted via the numerical models validated with experimental results. Furthermore, the theoretical formula for predicting the initial stiffness of Fe-SMA/steel bolted joints is proposed. The study indicates that when e/d rises from 1.0 to 4.0, the initial stiffness of single-hole Fe-SMA/steel bolted joints improves by 20% to 35%. The influence of edge distance on the initial stiffness of single-hole Fe-SMA/steel bolted joints is found significant but neglected by EN 1993-1-8. Compared with the recommended formula in EN 1993-1-8, the proposed theoretical formula improves the accuracy by 23% in predicting the initial stiffness of single-hole Fe-SMA/steel bolted joints. The research achievements contribute to the theoretical improvements in the reinforcement design of Fe-SMA in civil engineering.

Analysis and design recommendations for structures strengthened by prestressed bonded Fe-SMA

Previous studies have demonstrated a great potential of prestressed strengthening of structures employing iron-based shape memory alloys (Fe-SMAs). A bonded Fe-SMA strengthening solution with partial activation has been proposed. However, an analytical model for assessing the strengthening efficiency was lacking, due to the unique nature of the employed prestressing mechanism involving heating. In this study, a symmetric strengthening model and an asymmetric strengthening model are developed to analyze the prestress level in steel and glass beams and plates strengthened by bonded Fe-SMA strips. The asymmetric strengthening model is then modified to analyze reinforced concrete (RC) beams strengthened by embedded Fe-SMA rebars. Recovery stress at different activation temperatures, the influence of the activation temperature on the adhesive bond, as well as the prestress loss resulting from the deformation of substrate elements and adhesive joints are taken into account. The predicted strains and deflections in the parent structure closely approximate the experimental measurements that appear in current literature. A parametric study and a sensitivity analysis are then conducted to assess the impact of the four influential features on the final prestress level, and their impact is ranked in the following order: recovery stress ≈ Fe-SMA width > activation length > bonded anchorage length. Based on these findings, a design strategy, in line with Eurocode 0, for the bonded/embedded Fe-SMA strengthening system is proposed. Finally, some perspectives on potential areas for future research are offered.

Seismic performance of Fe-SMA prestressed segmental bridge columns with 3D printed permanent concrete formwork

The integration of digital fabrication technology with prestressed segmental column construction offers significant potential for accelerated bridge construction with material-efficient design. This study aims to explore this potential by developing a novel prestressed segmental column system that utilizes permanent 3D printed concrete (3DPC) formwork for column segment fabrication. Prestressing is achieved in the proposed system by using partially bonded iron-based shape memory alloy (Fe-SMA) reinforcement. Large-scale experiments were conducted on two columns under combined gravity and lateral loading to evaluate the seismic performance and feasibility of the proposed system. The ratio of steel to Fe-SMA reinforcement in the column design was the variable considered in this study. The experimental results showed that the columns could withstand lateral drifts of up to 5% without collapse and the permanent 3DPC formwork showed no premature failure or delamination. Furthermore, the columns exhibited self-centering characteristics, maintaining a residual drift of 1% up to a target drift of 4% when the reinforcement ratio of steel to Fe-SMA rebars was 0.3. The results highlight the potential of the proposed prefabrication concept in designing material-efficient and seismically resilient bridge columns with low damage characteristics.

Interrelationships of stress-induced martensitic phase transformation and pitting corrosion in iron-based shape memory alloys

Orientation dependence of stress-induced martensitic transformation under compression and the influence of a corrosion attack on superelastic properties were investigated for Fe42.7Mn34.7Al13.4Ni7.7Cr1.5 (at.−%) single crystals. The results of incremental strain tests show that the crystallographic orientation has a considerable impact on the superelastic performance, eventually resulting from the formation of twinned or detwinned martensite to accommodate strain as well martensite variant interaction. In order to investigate the effect of a corrosive environment on the mechanical performance and martensitic transformation, compression specimens were immersed in a 5.0 wt.−% NaCl solution for 24 h before tested in incremental strain tests. The immersion of the compression specimens revealed a partial surface corrosion attack including localized pitting corrosion. The localized corrosion attack increased the number of active martensite plates, most probably due to an induced multiaxial stress state. Further investigations on specimens subjected to −6% compressive strain revealed that areas with retransformed martensite serve as nucleation zones for corrosion damage. Stress-induced corrosion cracks developed, which eventually deteriorate functional response.

Eight-year natural environmental exposure and sustained-loading of reinforced concrete beams with iron-based shape memory alloys

Low-cost iron-based shape memory alloys (Fe-SMA) are recently proving to be favorable alternatives for strengthening reinforced concrete (RC) members. Unlike carbon fiber reinforced polymers (CFRP), Fe-SMAs eliminate the need for labor-intensive anchorages and exhibit plastic behavior similar to reinforcing steel, rendering them especially promising for prestressed near-surface mounted (NSM) applications. However, due to their recent development, not many long-term experimental studies have been yet available and thus the long-term durability of Fe-SMA-strengthened RC members remains relatively unexplored. To this end, the structural behavior of two RC beams strengthened with NSM Fe-SMA were investigated, exposed to a natural environmental conditions and sustained loading above their cracking load level for 8 years, followed by four-point bending until failure. Results were compared with a previous investigation of identical beams and Fe-SMA strips without exposure to environmental factors or sustained loading. Additionally, a comprehensive cross-section analysis (CSA) was conducted for both long-term exposure and four-point bending. Despite notable creep effects caused by the 8 years of sustained loading that accounted to approximately 55% of the total mid-span deflections, no significant differences were observed in terms of load-carrying capacity, ultimate deflections, or strains, compared to the unexposed beams. The employed CSA effectively captured the long-term and bending behavior. Additionally, a parameter study and global sensitivity analysis were conducted to identify influential parameters affecting structural performance, concrete compressive strength was found as the most dominant influencing parameter.

Proactive strengthening of U-rib butt-welded joints in steel bridge decks using adhesively bonded Fe-SMA strips

U-rib butt-welded joints are one of typical fatigue-prone details in early aging orthotropic steel bridge decks, which poses a potential threat to the structural behavior and safe operation of steel bridges. Therefore, it is of great importance to seek out an effective way for retrofitting fatigue cracks. This study proposes an efficient prestressing technique using bonded iron-based shape memory alloy (Fe-SMA) to strengthen cracked U-rib butt-welded joints proactively. A series of static and fatigue tests were conducted on the cracked specimens to investigate the feasibility and fatigue improvement of the proposed technique. Results from the experiments demonstrated that applying prestressing force by heating Fe-SMA strips is a convenient and reliable technique. Activated Fe-SMA strips could introduce significant compressive stresses and provide additional stiffness for the cracked components. This led to a reduction of the mean stress and fatigue stress ranges at the U-rib butt-welded joints under cyclic loading. All the cracked specimens strengthened with adhesively bonded Fe-SMA strips presented excellent fatigue performances, with a maximum equivalent fatigue life extension of 4.09 times compared to the specimen before cracking. Numerical simulation was also performed to better understand the test results. It was demonstrated that prestressed Fe-SMA strengthening could decrease the mode-I stress intensity factor (SIF) at the crack tip, indicating the beneficial effects of the prestressing in retarding crack and its further propagation. In conclusion, the use of adhesively bonded Fe-SMA strips for strengthening cracked butt welds is highly effective in improving the fatigue performance, even better than bonding CFRP.

Complete fatigue crack arrest in metallic structures using bonded prestressed iron-based shape memory alloy repairs

Vast aging metallic structures are suffering from fatigue cracking, jeopardizing structural integrity and personnel safety. Therefore it is of great benefit to develop strengthening solutions to achieve complete fatigue crack arrest. A bonded and prestressed fatigue strengthening solution on the basis of an iron-based shape memory alloy (Fe-SMA) shows great potential in this term. An experimental campaign has been carried out in this paper to achieve complete fatigue crack arrest in metallic plates. Several activation methods greatly affecting the prestressing level have been experimentally tested, it has been found that the gas torch activation is the most effective method, extending the fatigue crack growth life by 6.9 times. The experimental campaign has demonstrated that prestressing forces required to achieve complete fatigue crack arrest capability could be realized by increasing the Fe-SMA patch width combined with the most effective activation method. In addition, the results show that the length of the Fe-SMA repair together with the activation length can be reduced without sacrificing the repair efficiency. The findings of this paper are greatly beneficial for industrial sectors suffering from fatigue cracking in metallic structures, small bonded Fe-SMA patches can be easily activated to achieve complete fatigue crack arrest capability.

Mode I fracture analysis of Fe-SMA bonded double cantilever beam considering nonlinear behavior of the adherends

In the scope of developing a bonded iron-based shape memory alloy (Fe-SMA) strengthening solution, nonlinear deformation in the adherends upon joint failure due to phase transformation and high adhesive toughness is unavoidable. The effect of this nonlinear deformation has not been studied in the case of Mode I failure. In this study, the first experimental and theoretical investigation on Mode I failure of Fe-SMA bonded joints is presented. A new analytical model is proposed and validated using experimental results to gain an in-depth understanding of the influence of Fe-SMA nonlinear material deformation on the joint failure process. The proposed model is shown to be significantly faster than traditional elasto-plastic finite elements using cohesive zone modeling with a minimum compromise to the accuracy. These are observed to result in lower bond strength and a shorter fracture process zone than that of linear elastic adherends using the same adhesive. Neglecting the nonlinear behavior of the Fe-SMA bonded joints can lead to an unconservative joint design, jeopardizing safety. The developed model is aimed at facilitating the development of adhesively bonded Fe-SMA strengthening systems.

Shape memory alloys effects on the multi-story structures under extreme loading conditions

The use of intelligent materials with particular behavioral traits has grown significantly in recent years. The most common materials that may revert to their original shape after deformation due to stress or heat change are shape memory alloys (SMAs). Shape memory alloy (SMA) differs from conventional materials due to its shape memory property and hyperplastic nature. This research aims to explore the use of SMAs as a reinforcement to improve the performance of multi-story steel plate shear walls (SPSW) under explosive loading. The finite element (FE) software "ABAQUS" is utilized to simulate the models, and the results of the numerical modeling are validated against experimental research from the literature. The study investigates the impact of different parameters related to the explosion on the behavior of the reinforced multi story SPSW, including the amount of explosive material and the location of the explosion. The findings reveal that the minimum amount of explosive material required to cause rupture in a four-story SPSW reinforced by SMA, positioned at a distance of 1 m from the structure, is equivalent to 40 kg of TNT. Additionally, the minimum distance required for element rupture in the four-story SPSW, reinforced by SMA strips, is found to be 0.5 m. As the explosion height increases, the amount of out-of-plane base shear decreases. Furthermore, an interesting observation is that as the explosion height increases, the displacement of the infill plate also increases, leading to beam failure and, ultimately, infill plate failure. Niti SMA exhibited superior blast resistance compared to Iron-based SMA, showcasing its potential for enhancing structural resilience.