Shape Memory Alloy Rebars Research Articles

Fatigue behavior of RC beams strengthened with iron-based shape memory alloy rebars

This paper presents the experimental research results on the fatigue behavior of reinforced concrete (RC) beams integrated with prestress using iron-based shape memory alloys (Fe-SMAs). Four RC beams reinforced with Fe-SMA rebars as tensile members were fabricated for the fatigue experiments. The experimental variables included the type of load (static and fatigue) and the size of the fatigue load (40 %, 50 %, and 60 % of the maximum load). Before the experiments, prestress was introduced into the Fe-SMA rebars through electric resistance heating. The minimum load for the fatigue test was set at 20 % of the maximum load of the control beam, and the tests were conducted at a frequency of 2 Hz. As the number of fatigue load cycles increased, all specimens exhibited an increasing trend in deflection and strain. The specimens subjected to fatigue loads of 50 % and 60 % of the maximum load failed due to the crushing of the compression concrete and the fracture of the Fe-SMA rebars, respectively. In contrast, the specimen subjected to 40 % of the maximum load showed a similar load resistance capacity to the control beam even after enduring 2 million cycles of fatigue load.

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.

Shape memory alloy-reinforced UHPC tube confined bridge piers for enhancing the seismic resistance of highway bridges

Multi-span continuous highway bridges supported with reinforced concrete (RC) bridge piers may experience large permanent deformation after strong earthquakes. To overcome the limitations, an innovative UHPC tube-confined SMA reinforced bridge pier, i.e., shape memory alloy (SMA) replacing the steel rebars at the plastic hinge region and a prefabricated UHPC tube substituting the cover concrete, is proposed. To fully utilize the tensile strength of UHPC, the UHPC tube is embedded into the foundation. A performance-based seismic design procedure considering target residual drift as engineering demand parameter (EDP) is proposed to design this novel UHPC-SMA pier. The seismic responses of novel bridge systems supported by UHPC piers (Bridge II) and UHPC-SMA piers (Bridge III) are investigated and compared with reference bridge (Bridge I) having RC piers. The results indicate that both UHPC piers and UHPC-SMA piers are efficient in improving the seismic resistance of highway bridges. Compared with Bridge I, the prefabricated UHPC tube significantly decreases the residual deformation of Bridge II piers by 22.9 % as a result of the bridging effect of steel fibers. Due to the excellent self-centering property of SMA, the residual deformation of Bridge III piers decreases further by 57.8 % in comparison to reference bridge. The UHPC tube increases the low stiffness of bridge piers caused by SMA rebars at the plastic hinge region. The combination of UHPC tube and SMA can effectively prevent core concrete from severe damage with less dissipated energy of bridge piers.

Behavior of Smart Beams Reinforced with Superelastic Shape Memory Alloy Rebar (SMA)Subjected to Repeated Loading

A reinforced concrete beam with shape memory alloy rebar (SMA) is a novel form of smart beam used in smart seismic structural systems to reduce the effects of earthquakes while keeping nearly the same load-carrying capability as conventional concrete beams. The experimental research investigation is carried out to study beams' flexural behavior by replacing some steel rebars with shape memory alloy rebars (SMAs) in the longitudinal reinforcement zone. The experimental program included testing three beams to investigate the effects of the replacement of longitudinal steel rebar by shape memory alloy rebar on the flexure behaviour of beams. The beams were tested by the repeated load. The study was focused on determining ultimate load, maximum deflection, and load-deflection behaviour. Experimentally, the flexure behaviour beams are significantly affected by changing the number of reinforcing bars with shape memory alloys (SMA) longitudinal direction. However, for using one rebar of shape memory alloy as a longitudinal reinforcement, the replacement of one bar and two bars of shape memory alloy SMA beams have less yield load than the control beam by about (12.5%) and (37.5%) respectively. The replacement of one bar and two bars of shape memory alloy SMA beams having less ultimate load compared with reference beam by about (9.82%) and (21.94%) respectively. Because of its superelasticity quality, the introduction of superelastic SMA bars to the beam shows excellent recentering ability.

Experimental study on the active continuity of HCS structural floors using Iron-based Shape-Memory Alloy rebars

Despite the relatively recent introduction of Iron-based Shape-Memory Alloys (Fe-SMA) into structural engineering, more than 150 real applications have been performed to date in Central Europe, especially in retrofitting projects. Thanks to the Shape-Memory Effect, a prestrained and correctly anchored Fe-SMA bar can generate recovery stresses when heated up to 160 °C (activation) or more, and then cooled down. This paper presents research results about using Fe-SMA reinforcing bars as active (prestressed) continuity reinforcement in the hogging bending moment region of Hollow Core Slabs structural floors (HCS-sf). An experimental campaign was designed and carried out on eight HCS-sf specimens, four with concrete topping and four without, and two different slab heights. Using the HCS-sf specimens with the activated Fe-SMA bars resulted in better behaviour in the Service Limit State, which preliminarily proved the effectiveness of the proposed methodology for the specimens with concrete topping, although construction problems arose with the specimens without concrete topping.

Potential of Fe-Mn-Al-Ni Shape Memory Alloys for Internal Prestressing of Ultra-High Performance Concrete.

Prestressing of concrete is a commonly used technique in civil engineering to achieve long spans, reduced structural thicknesses, and resource savings. However, in terms of application, complex tensioning devices are necessary, and prestress losses due to shrinkage and creep of the concrete are unfavourable in terms of sustainability. In this work, a prestressing method using novel Fe-Mn-Al-Ni shape memory alloy rebars as a tensioning system in UHPC is investigated. A generated stress of about 130 MPa was measured for the shape memory alloy rebars. For the application in UHPC, the rebars are prestrained prior to the manufacturing process of the concrete samples. After sufficient hardening of the concrete, the specimens are heated inside an oven to activate the shape memory effect and, thus, to introduce the prestress into the surrounding UHPC. It is clearly shown that an improvement in maximum flexural strength and rigidity is achieved due to the thermal activation of the shape memory alloy rebars compared to non-activated rebars. Future research will have to focus on the design of the shape memory alloy rebars in relation to construction applications and the investigation of the long-term performance of the prestressing system.

Seismic performance of precast CFDST segmental column with hybrid energy dissipation devices

Precast segmental column has various advantages as compared to traditional cast in-situ monolithic column. The major issues of such column are the concrete compressive damages at the toes of the segments and limited energy dissipation due to the rocking mechanism. This study explores a new design of precast segmental column with damage resistant features and hybrid energy absorption system. Super elastic shape memory alloy (SMA), external energy dissipation devices and concrete-filled double-skin steel tubes (CFDST) segments are used to form a seismic resilient precast segmental column. Specifically, the SMA rebars provide the column with good self-centring ability; the external replaceable energy dissipation devices provide extra energy dissipation capacity; the use of CFDST segments mitigates the concrete damage. It is found that the proposed column performs well with small residual displacement, satisfying energy dissipation and minor damage.

Numerical Investigation of Shape-Memory Alloy–Reinforced Bridge Columns Subjected to Lateral Impact Loads

This paper numerically investigates the dynamic behavior of bridge piers reinforced with shape-memory alloy (SMA) rebar when subjected to lateral impact loads. Performance of SMA reinforced pier is compared with column reinforced by conventional steel rebar by performing finite-element (FE) simulations in LS-DYNA. The impact performance of the columns is evaluated by considering variations in different structural- and loading-related parameters including the type of SMA rebar, the length of SMA rebar (LSMA), the impact velocity (Vimp), and the axial load ratio (ALR). From the FE simulations, it is found that the use of SMA rebars at the plastic hinge regions and the impact loading height of the columns significantly enhances the impact resistance and the recoverability of the columns by reducing their damage levels and residual displacements. Also, the failure modes of the columns tend to govern by flexure by using SMA rebars, and the columns reinforced with Cu-based (Cu–Al–Mn) SMA rebars are more likely to fail in flexural modes compared to those reinforced with Ni-based (Ni–Ti) SMA rebars. However, the negative influences of SMA rebars on the impact resistance of the columns are found when LSMA exceeds 0.5 under impact loads with velocities greater than 15 m/s. In addition, an ALR greater than 0.1 considerably increases the impact resistance of the columns.

From experimental strain and crack distributions to plastic hinge lengths of RC walls with SMA rebars

Modern-designed reinforced concrete walls can typically achieve the primary performance level of collapse prevention in a moderate-to-large earthquake event. However, the substantial amount of damage sustained by the wall can result in large residual displacements of a building, often requiring costly repairs or even demolition. Localised replacement of reinforcing steel for a pseudoelastic material, such as shape memory alloys, has been offered as a potential solution for reducing residual displacements of reinforced concrete walls. This paper examines two basic assumptions that can be employed for the simulation of reinforced concrete walls with shape memory alloy rebars using distributed and lumped plasticity line models, namely: plane-sections-remain-plane and plastic hinge length. To this purpose, the authors analyse the strain and crack distributions using the experimental data from a recent experimental campaign. Digital image correlation techniques were used to capture the displacement field of the surface of the walls. Experimental findings are presented, including crack distributions and salient crack widths, longitudinal strain profiles along the wall length and height, and curvature profiles. They are used to discuss the validity of the plane-section hypothesis and equivalent plastic hinge length expressions. A conventional wall reinforced with steel rebars is used for comparison purposes. The experimental results presented in this paper are useful for the ongoing international investigations on concrete structures detailed with shape memory alloys.

Dynamic behavior of bridge columns reinforced with shape memory alloy rebar and UHPFRC under lateral impact loads

This paper numerically evaluates the combined effect of ultra-high-performance fiber-reinforced concrete (UHPFRC) jacket and shape memory alloy (SMA) rebar on the dynamic response of a reduced-scale bridge pier under lateral impact loads of different velocities. The performance of the columns is assessed considering the variations of different parameters including the type of SMA rebars, thickness of UHPFRC jacket (tU), impact velocity (Vimp), and axial load ratio (ALR). From the FE simulations, it is found that the SMA rebars have a more positive influence on the lateral strength of the conventional columns with normal concrete (NC) compared to UHPFRC-strengthened columns when subjected to impact loadings at 5 m/s and 15 m/s velocities that represent relatively low- and medium-rate impacts, respectively. However, the positive effect of the SMA rebar is more pronounced on the resistance of UHPFRC-strengthened columns under a high-rate impact loading with Vimp = 25 m/s. In addition, a 60 mm-thick UHPFRC jacket is recognized as the optimal level based on the behavioral trend of the UHPFRC-strengthened columns when they are subjected to impact loads with velocities higher than 10 m/s (representing a medium-rate impact). From the evaluation of the effectiveness of ALR, an absolute positive influence of ALR on the impact resistance of the steel-reinforced columns is found when it ranges between 0.1 and 0.15. However, the increase of ALR beyond a critical value of 0.125 demonstrates a negative influence on the lateral strength of SMA-reinforced UHPFRC columns.

Drift limit state predictions of rectangular reinforced concrete columns with superelastic shape memory alloy rebars

This study derives empirical drift limit state expressions for rectangular concrete columns reinforced with nickel–titanium shape memory alloy (SMA) bars using numerical simulation results obtained from well-calibrated nonlinear finite element models. A parametric study is conducted to examine the effects of various design parameters, such as the axial load ratio, section information, and material properties of concrete and SMA on the drift limit states of the columns. For each limit state (LS), a multivariate stepwise regression analysis was performed. An expression was derived to estimate the associated drift capacity of the SMA-reinforced concrete columns. In addition, the precondition for the SMA-reinforced concrete columns to ensure ductile behavior was investigated. It turned out that the axial load and the amount of transverse reinforcement are the most influential parameters on the ductility of the columns. Finally, nonlinear static and dynamic analyses were conducted for an SMA-reinforced concrete building frame to demonstrate the application of the proposed drift LSs. Both analysis results revealed that the building model tends to experience core crushing or loss of lateral load capacity prior to SMA failure.

Uniaxial behavior of pre-stressed iron-based shape memory alloy rebars under cyclic loading reversals

Iron-based shape memory alloys (Fe-SMA) have recently emerged as a promising alternative for structural design and retrofitting due to their unique self-prestressing ability. The feasibility of using Fe-SMA rebars, strips, and stirrups for improving the flexural and shear behavior of reinforced concrete beams and slabs has been successfully demonstrated in many experimental investigations. However, existing studies have mostly focused on applications where structural elements are subjected to monotonic loading. On the other hand, tension-compression reversals are mostly experienced by the reinforcement under seismic actions, which makes it necessary to characterize the pre-stress behavior of Fe-SMA under cyclic loading reversals. More specifically, it is important to identify the limit associated with the complete loss of pre-stress of Fe-SMA under tension-compression reversals. Another important research gap is the lack of understanding of the inelastic buckling behavior of Fe-SMA rebars, which is also important for the application of Fe-SMAs in seismic design and retrofitting. Specifically, an understanding of the inelastic buckling behavior is needed for determining the spiral spacing and accurate moment-curvature analysis of cross-sections of concrete columns reinforced with Fe-SMA rebars. This study aims to address these important research gaps by experimentally evaluating the stress-strain behavior of pre-stressed Fe-SMA rebars under cyclic tension-compression reversals. The outcome of this study will facilitate in developing accurate analytical and numerical models for estimating the cyclic response of Fe-SMA rebars and will also assist in developing design guidelines for the use of Fe-SMA in seismic applications.

Residual displacements of reinforced concrete walls detailed with conventional steel and shape memory alloy rebars

Modern reinforced concrete design codes can generally achieve the primary performance level of no collapse in the event of a rare to very rare earthquake. However, recent seismic events have shown that permanent damage and deformations of buildings prevent the structure from being serviceable, imposing high costs associated with repairs or demolition. Shape memory alloys have the ability to recover large strains upon removal of stress. Thus, replacing conventional steel with superelastic alloy rebars in the boundary ends of reinforced concrete walls has the potential to reduce residual seismic displacements for these types of buildings. This research paper investigates the lateral residual displacement of reinforced concrete walls detailed with conventional steel and shape memory alloy bars as a function of the in-plane drift. Namely, the force-displacement hysteresis of a large dataset of experimental walls with conventional steel are used to study the residual displacement as a function of several key design parameters. A state-of-the-art finite element modelling program is then used to investigate the residual displacements of walls detailed with shape memory alloy bars, and a parametric study is undertaken to investigate the influence of residual displacements of these types of walls. Most of the walls reinforced with shape memory alloys achieved residual displacements less than the permissible limit at large drift levels. The axial load was found to help suppress the residual displacements of walls with increasing drift. The curvatures were found to be distributed over a limited height at the base that was equivalent to the length of the shape memory alloy bar used. Plastic hinge analysis expressions are adapted to estimate the operational displacement of reinforced concrete walls with shape memory alloys.

Flexural Behavior of RC Beams Using Fe-Based Shape Memory Alloy Rebars as Tensile Reinforcement

Recently, various studies for the use of Fe-based shape memory alloy (Fe-SMA) in the construction field have been widely conducted. However, most of the studies for using Fe-SMA are carried out for applying Fe-SMA for strengthening deteriorated structures. However, if Fe-SMA is used as a reinforcement for new structures, the disadvantages of conventional prestressed concrete can be effectively solved. Therefore, in this work, an experimental study was conducted to evaluate the flexural behavior of concrete beams in which Fe-SMA rebars were used as tensile reinforcement. For the study, ten specimens were constructed with the consideration of the cross-sectional area and activation of Fe-SMA rebars as experimental variable. Activation of the Fe-SMA rebars by electrical resistance heating applied an eccentric compressive force to the specimen to induce camber. The camber increased by an average of 0.093 mm as the cross-sectional area of the Fe-SMA rebar increased by 100 mm2. It was also confirmed through the four-point bending tests that the initial crack loads of the activated specimens were 47.6~112.8% greater than those of the nonactivated specimens. However, the ultimate strength of the activated specimens showed a slight difference of 3% to those of the nonactivated specimens. Therefore, it was confirmed that the effect of Fe-SMA activation on the ultimate strength of specimens was negligible.

Flexural Behavior of Self-Prestressed RC Slabs with Fe-Based Shape Memory Alloy Rebar

A lot of studies have been conducted to introduce self-prestress to structures using Fe-based shape memory alloys (Fe-SMAs). Technology to introduce self-prestress using Fe-SMAs can resolve the disadvantages of conventional prestressed concrete. However, most of the research to introduce a self-prestress force to a structure using Fe-SMAs has been focused on using Fe-SMAs for the repair and strengthening of aging structures. Therefore, in this paper, a study was conducted to introduce self-prestress into a new structure. To this end, in this paper, an experimental study was conducted to evaluate the flexural behavior of self-prestressed concrete slabs with Fe-SMA rebar. Nine specimens were built with consideration of the amount and activation of Fe-SMA rebars as experimental variables. The Fe-SMA rebars used in the specimens exhibited recovery stress of about 335 MPa under the conditions of a pre-strain of 0.04 and a heating temperature of 160 °C. Activation of the Fe-SMA rebars by electrical resistance heating applied an eccentric compression force to the specimen to induce a camber of 0.208–0.496 mm. It was confirmed through a 4-point bending test that the initial crack loads of the activated specimens were 40~101% larger than that of the non-activated specimens. However, the ultimate loads of the activated specimens showed a difference within 3% from that of the non-activated specimens, confirming that the effect of activation on improving the ultimate strength was negligible. Finally, it was confirmed that repetitive activation of the Fe-SMA rebar could repeatedly apply compressive force to the slab.

Impact of ground motion duration on concrete shear walls reinforced with different types of shape memory alloy rebars

The impact of ground motion duration often arises when investigating buildings’ performance in regions susceptible to strong earthquakes, where reinforced concrete (RC) shear walls are typically used as a lateral force-resisting system. Although the seismic performance of these reinforced walls has been improved by the use of self-centering devices and materials, the influence of ground motion duration on self-centering RC walls is not yet well understood. This paper, therefore, examines the effect of ground motion duration on seismic performance and the damage scheme of the self-centering shear wall reinforced with three different types of superelastic shape memory alloy (SE-SMA) in the plastic hinge. A ten-story case study building was analyzed and designed according to the current ASCE 7-16 and ACI-318 practice codes. The maximum inter-story drift ratios (IDR), residual drift ratios (RIDR), shear forces, bending moments, material damages, and collapse margin ratios were examined. The results indicate that IDR and RIDR significantly increased as ground motion duration increased. Meanwhile, the shear forces increased by about 24% on average, which induced only a 6% increase in the bending moments. It was also observed that ground motion duration significantly influenced the scaling factor required to reach the collapse level. Among the examined SE-SMA RC walls, the results indicate that Cu-based SMA RC wall exhibits superior performance in terms of IDR, RIDR, shear forces, and bending moments and performs fairly well in terms of material damage and collapse margin ratio compared to other SMA RC walls. Thus, using Cu-based SMA material in seismically active regions prone to short and long duration ground motions is generally recommended.

Performance evaluation of RC-MRFs with UHPSFRC and SMA rebars subjected to mainshock-aftershock sequences

Although structures are generally subjected to mainshock-aftershock sequences, the current structural design process merely considers the main seismic event. This study aims to compare the performance of Reinforced Concrete Moment Resisting Frames (RC-MRFs) with Shape Memory Alloy (SMA) and Ultra-High-Performance Steel Fiber Reinforced Concrete (UHPSFRC) under the influences of mainshock and aftershock sequence. To achieve this aim, 3, 6, and 8-story five-span frames were simulated considering three different approaches: (i) RC frames; (ii) RC frames with SMA rebars in the plastic hinge length of the beams; (iii) RC frames with UHPSFRC and SMA in the plastic hinge length of the beams.Each frame was analyzed under two different scenarios, with and without considering seismic sequences to assess the post-earthquake performance of damaged RC frames. Time history analyses were conducted using seven real accelerograms. Maximum transient inter-story and roof drifts, as well as residual inter-story drifts, were determined and compared in undamaged and damaged structures to assess the effect of seismic sequence. As the performance evaluation of the damaged structures appears to be essential to make repair policy decisions and rescue operations, damage states were defined according to FEMA-356 based on maximum transient and residual drifts. Numerical results illustrate the salient effect of using SMA and UHPSFRC synergistically in reducing transient and residual drifts and enhancing the functionality of structures in both mainshock and aftershock.

Seismic Performance Evaluation of Shape Memory Alloy (SMA) Reinforced Concrete Bridge Bents Under Long-Duration Motion

The emergence of the Shape Memory Alloy (SMA) rebar has paved the way towards resilient bridge design through improved post-earthquake functionality. The focus of this study is to numerically examine the effects of SMA rebar inclusion on the seismic performance of a reinforced concrete (RC) bridge bent under long-duration motions and perform a comparative analysis with the conventional steel-reinforced bridge bent. The duration effect is examined by assembling a pair of forty long-duration and spectrally equivalent short duration motions, without considering the pulse-nature of ground motions. Three different reinforcement configurations, with and without SMA rebar in the bridge bent bottom and top plastic hinge, are considered here. Using the selected ground motions, incremental dynamic analysis (IDA) is conducted to examine the duration effect considering different performance indicators such as maximum drift and residual drift. For residual drift, the dominance of ground motion duration is observed which is found to have a lesser impact on the SMA reinforced bents. The detrimental effect of long-duration motion is more pronounced for the steel-reinforced bridge bent compared to the SMA reinforced bents.

Seismic performance assessment of a multispan continuous isolated highway bridge with superelastic shape memory alloy reinforced piers and restraining devices

AbstractThe objective of this study is to analytically determine the effectiveness of a novel bridge system with superelastic (SE) shape memory alloy (SMA) reinforced concrete piers. The bridge is also equipped with SE SMA cable restrainers to prevent the bridge spans from a large displacement that can potentially cause span unseating. In the concrete bridge piers, the conventional steel reinforcements in the plastic hinge regions are replaced with SE SMA rebar to avoid large plastic deformation and improve its self‐centering capacity. A typical three‐span continuous highway bridge is modeled with SMA‐reinforced piers and SMA restrainers. Numerical simulations of the bridge are conducted under destructive near‐fault ground motions. The seismic responses and fragility curves of the novel bridge (Bridge IV) are assessed and compared with the reference bridge (Bridge I), the bridge with only SMA‐reinforced piers (Bridge II), and the bridge with only SMA restrainers (Bridge III). The results revealed that the SMA‐reinforced pier can successfully reduce the residual deformation and damage probability of the bridge; however, the bridge with only SMA‐reinforced piers is less efficient in preventing a large displacement. The use of SMA restrainers can efficiently limit the displacement of the bridge spans but increase the damage probability of the bridge piers. The proposed novel bridge having SMA‐reinforced piers equipped with SMA restrainers (Bridge IV) is more efficient than the bridge with only SMA‐reinforced piers (Bridge II)) or the bridge with only SMA restrainers (Bridge III).

Seismic investigation of longitudinally aligned shape memory alloy-stainless steel reinforced concrete column

Shape memory alloy (SMA) is a smart material sustain (8∼13%) an enormous amount of strain and having an ability to regain parental shape after the removal of an external load and temperature due to its pseudo-elastic (SE) and shape memory effect (SME) properties. The SE and SME properties, lower modulus of elasticity, and higher elastic straining of SMA compared to conventional steel reinforcement makes it predictable for the design of the reinforced concrete (RC) structure. The present research is focused on the seismic investigation of RC columns reinforced with SMA rebar in the plastic hinge region along with stainless steel (SS) in the remaining portion of the column. A nonlinear static pushover seismic analysis is used for the numerical investigation of SMA-SS RC column. The numerical model is validated having 98% accuracy with existing literature results. The impact of various parameters on SMA-SS RC column is evaluated for SMA in the plastic hinge region. The results reveal that an aspect ratio, the yield strength of reinforcement, the compressive strength of concrete and axial load are significantly affecting the lateral strength and the ductility of the column under seismic loading.