Low Fatigue Resistance Research Articles

New Models for the Properties of Warm Mix Asphalt with Sasobit

Warm Mix Asphalt (WMA) is a set of technologies that uses additives to reduce binder viscosity and increase mixture workability, which provides a complete coating of aggregates at lower temperatures around 100 °C to 130 °C. Organic wax or Sasobit is one of the additives that can be used for this purpose. It reduces the viscosity at the melting point of the wax, which allows the production of asphalt mixes at lower temperatures. This attempt proposes new relationships for elastic modulus, indirect tensile strength (in dry and wet conditions), dynamic modulus, fatigue, and rutting resistance of WMA asphalt samples with various Sasobit percentages. Findings show that Sasobit improves modulus of elasticity, dynamic modulus, and rutting resistance. However, it lessens the tensile strength slightly. Although Sasobit enhances the flexural stiffness, it drops the number of loading cycles, which means lower fatigue resistance. Results also showed that at 20 °C and 10 Hz frequency, the resilient modulus, dynamic modulus, and flexural stiffness of WMA improved 53%, 27%, and 39%, respectively, compared with HMA. Rutting resistance at 60 °C improves 226% in WMA with 6% Sasobit compared to the HMA mix.

Study of the Rotary Bending Fatigue Resistance of 30MnB5, 41CrS4 and 30MnVS6 Steels

In this study, a comparative analysis of the fatigue behavior of four types of steels, three of quenching and tempering (30MnB5 subjected to two different heat treatments and 41CrS4) and one microalloyed (30MnVS6), was carried out. The objective of the study is to determine if it is feasible to replace the quenching and tempering steel traditionally used in the manufacture of commercial vehicle axles (30MnB5) with alternative ones with the same composition but with modifications in their microstructure that improve their mechanical properties; a quenched and tempered chromium steel (41CrS4) and one that is microalloyed (30MnVS6). For this, rotary-bending fatigue tests have been carried out on the four types of steels with different stress levels. The fatigue resistance of quenched and tempered steels and microalloyed steel was evaluated using the fit of Basquin’s experimental data. Where possible, the fatigue limit was determined using the maximum likelihood method. It was concluded that, in general, the fatigue resistance of chromium-alloyed steel is higher than that of the reference steel, while the rest have lower fatigue resistance. On the other hand, it was determined that the fatigue limit of microalloyed steel is higher than the reference one and that of the reference steel is higher than that of the other two steels.

Investigation of average asphalt film thickness of dense graded asphalt mixtures with compaction effects

The asphalt mixtures with inadequate durability may become too lean, resulting in low rutting and fatigue resistance. The asphalt film thickness (AFT) has been used as a crucial property for the durability of asphalt mixtures. However, the relationship between AFT and volumetric properties is ambiguous with the absence of compaction effects in the standard film thickness equation. This study aims to investigate the relationship between AFT and volumetric properties of dense-graded asphalt mixtures with consideration of the compaction degree. The compaction-property-dependent (CPD) AFT model considering compaction effects was proposed and compared with the standard AFT equation. Then, asphalt mixtures with 112 different gradations were used to calculate the AFT with and without compaction effects. The relationship between new AFT and volumetric parameters (Pb, VMA, VFA, Vc, Vfine and Vfiller) was investigated by linear correlation analysis. After that, two regression models and a back-propagation (BP) neural network were used to predict the new AFT with volumetric parameters. By comparing the prediction accuracy of these models, a reasonable model with higher prediction accuracy was selected. Results show that the new AFT is 2% to 30% less than the AFT in the standard model, and the surface area of air void boundary has a negative effect on the new AFT. The correlation analysis indicates that the new AFT of dense-graded asphalt mixtures has a rough correlation with changes in VMA, binder content and VFA. The prediction accuracy of the BP neural network has the highest R-squared. The relative importance and sensitivity analysis of the BP neural network verified a relatively good relationship between VMA and new AFT. These findings can give a considerable interest for the tendency of using the new AFT to supplement the current specified VMA criteria.

Effect of A Clinical-Replicable Cooling Protocol on the Cyclic Fatigue Resistance of Heat-Treated Nickel-Titanium Instruments.

The aim of this study was to evaluate the bending and cyclic fatigue resistance of Wave One Gold (WOG) and X1 Blue (X1B) instruments when tested at body temperature (36°C ± 1°C) with and without subjected to an alloy cooling protocol. A total of sixty instruments (n=30) were tested. Forty instruments (n=20) were randomly selected and divided into two groups: body temperature (BT; n=20) and body temperature with cooling protocol (CP; n=20). Cyclic fatigue test was performed until fracture in a conventional stainless-steel device with water bath equipment to simulate body temperature. CP group instruments were subjected to 5 seconds of spray cooling every 30 seconds. Time to fracture was recorded in seconds. Resistance to bending at an angle of 45 degrees was evaluated using twenty instruments (n=10). Fractured surfaces were examined under scanning electron microscopy (SEM). Statistical analysis was performed at a 5% significance level. Results: There was no difference in the cyclic fatigue resistance between instruments in BT groups (P>0.05). Cooling protocol significantly increased the cyclic fatigue resistance of X1B instruments (P=0.0003) and WOG instruments (P=0.0003). WOG instruments had a significantly lower cyclic fatigue resistance compared to X1B instruments in CP group (P=0.0001). There were no significant differences between the values of resistance increase presented by the instruments after cooling (P>0.05). Bending test presented no statistically significant differences between the tested instruments (P>0.05). Both instruments in both groups showed typical features of cyclic fatigue behavior under SEM. X1 Blue #25.06 and WaveOne Gold #25.07 instruments presented similar cyclic fatigue resistance. The investigated clinical-replicable cooling protocol improved the cyclic fatigue resistance of the tested instruments, with X1 Blue #25.06 presenting a greater cyclic fatigue resistance after cooling. Both instruments presented a similar bending capacity.

Preparation, mechanical properties, fatigue and tribological behavior of double crosslinked high strength hydrogel

Polyvinyl alcohol hydrogel (PVA-H) has been widely used in clinical transplantation because of its high water content, good biocompatibility and mechanical properties. However, PVA-H have some problems, such as low elongation at break, low fatigue resistance and high friction coefficient, which hinders its application in clinic. In this paper, a novel high-performance PVA hydrogel enhanced by chemical double crosslinking (CDC) method had been synthesized. The influences of chemical crosslinking agent concentration on mechanical properties, friction properties and fatigue properties of materials were systematically investigated, in order to meet the clinical application of artificial meniscus, artificial cartilage, nucleus pulposus and so on. As a result, due to the introduction of chemical bonds, CDC hydrogels have over 600% elongation at break, modulus loss after fatigue test was reduced by 42%, average coefficient during friction was reduced to 0.048, and biocompatibility performance was excellent. The PVA hydrogel enhanced by CDC method provides a new concept for us to prepare high-performance PVA hydrogel and a promising material to replace cartilage, meniscus, nucleus pulposus and other tissues.

Investigation on aging resistance of ternary compound carbon nitride (CN-Bi-Tr-DC) modified asphalt

Asphalt aging is one of the key factors affecting the service life of asphalt pavement. Asphalt materials are prone to irreversible performance degradation under ultraviolet (UV) irradiation. In this study, a ternary composite carbon nitride modifier (CN-Bi-Tr-DC) with excellent compatibility with asphalt binder was prepared. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and ultraviolet visible near infrared spectroscopy (UV–Vis-NIR) were used to characterize the micro morphology and light absorption rate of the modifier. The results showed that the long organic chains were successfully grafted onto the surface of the ternary composite carbon nitride modifier. In addition, the ultraviolet absorption rate of CN-Bi-Tr-DC is 65%. Dynamic shear rheometer (DSR) was used to investigate the high and low temperature performance and fatigue resistance of CN-Bi-Tr-DC modified asphalt. CMAI, G-RAI, ICO and ISO were used to evaluate the long-term aging performance of CN-Bi-Tr-DC modified asphalt. The test results demonstrated that the addition of CN-Bi-Tr-DC could improve the anti-ultraviolet aging performance of asphalt binder, and the improvement effect was most obvious when the content of CN-Bi-Tr-DC was 2–4%.

Influence of types and shapes of 3D printed polymeric lattice on ductility performance of cementitious backfill composites

The compression properties of cementitious backfill composite (CBC) is strong, but their tension properties are weak and presents little ductility because of their low fatigue crack growth rate and resistance. Thus, proper reinforcement techniques are needed to improve CBC’s ductility without rupture. This paper deals a system for boosting CBC’s ductility by reinforcing it with several types (e.g., ordinary resin OR, transparent resin TR, and nylon NY) and shapes (e.g., hexagon, cube, and rhombus) of 3D printed polymeric lattice (3D PPL) by agreeing the digital image correlation method. Specimens were subjected to three-point bending and SEM experiments to study their flexural and microstructural behavior. Results shown that: the flexural strengths of OR and NY 3D PPL reinforced CBC specimens were larger than TR and non-3D-PPL (N-3D-PPL) reinforced ones. But TR 3D PPL reinforcement effect was not so vibrant. For an ideal flexural strength, the best type and shape of 3D PPL were OR and rhombus, respectively. The deflection of 3D-PPL reinforced CBC specimens was larger than those N-3D PPL reinforced ones. For an ideal deflection value, the optimal shape and 3D PPL types were cube and OR. 3D PPL reinforced CBC specimens exhibited great ductility and toughness while N-3D PPL reinforced ones exhibited obvious brittleness. The most abundant elements were oxygen, calcium, and silicon, which gathered in the large amounts around C-S-H gels’ location. Finally, the outcomes of this work state that 3D PPL has great potential for converting brittle CBC into a ductile material without dropping its hardening performance.

Recent advances of high entropy alloys for aerospace applications: a review

PurposeThis study aims to review the recent advancements in high entropy alloys (HEAs) called high entropy materials, including high entropy superalloys which are current potential alternatives to nickel superalloys for gas turbine applications. Understandings of the laser surface modification techniques of the HEA are discussed whilst future recommendations and remedies to manufacturing challenges via laser are outlined.Design/methodology/approachMaterials used for high-pressure gas turbine engine applications must be able to withstand severe environmentally induced degradation, mechanical, thermal loads and general extreme conditions caused by hot corrosive gases, high-temperature oxidation and stress. Over the years, Nickel-based superalloys with elevated temperature rupture and creep resistance, excellent lifetime expectancy and solution strengthening L12 and γ´ precipitate used for turbine engine applications. However, the superalloy’s density, low creep strength, poor thermal conductivity, difficulty in machining and low fatigue resistance demands the innovation of new advanced materials.FindingsHEAs is one of the most frequently investigated advanced materials, attributed to their configurational complexity and properties reported to exceed conventional materials. Thus, owing to their characteristic feature of the high entropy effect, several other materials have emerged to become potential solutions for several functional and structural applications in the aerospace industry. In a previous study, research contributions show that defects are associated with conventional manufacturing processes of HEAs; therefore, this study investigates new advances in the laser-based manufacturing and surface modification techniques of HEA.Research limitations/implicationsThe AlxCoCrCuFeNi HEA system, particularly the Al0.5CoCrCuFeNi HEA has been extensively studied, attributed to its mechanical and physical properties exceeding that of pure metals for aerospace turbine engine applications and the advances in the fabrication and surface modification processes of the alloy was outlined to show the latest developments focusing only on laser-based manufacturing processing due to its many advantages.Originality/valueIt is evident that high entropy materials are a potential innovative alternative to conventional superalloys for turbine engine applications via laser additive manufacturing.

Stepwise stress testing of different CAD-CAM lithium disilicate veneer application methods applied to lithium disilicate substructures

Statement of problemWhether a computer-aided design and computer-aided manufacture (CAD-CAM) fabricated high-translucency lithium disilicate veneer on a lithium disilicate substructure would increase the strength of the restoration compared with a traditional feldspathic porcelain veneer is unclear. PurposeThe purpose of this in vitro study was to evaluate the effect of different lithium disilicate veneer application methods on a lithium disilicate substructure on their biaxial flexural stress (BFS). Material and methodsLithium disilicate disks were fabricated so that when combined with the veneering disks, they had a dimension of 12×1.2 mm. Experimental groups were as follows (n=15): resin-bonded lithium disilicate veneer, lithium disilicate veneer adhesively cemented to lithium disilicate; sintered lithium disilicate veneer, lithium disilicate veneer sintered to lithium disilicate; sintered feldspathic veneer, feldspathic porcelain applied to lithium disilicate; and monolithic lithium disilicate, the control group. Weibull distribution survival analysis was used to compare the differences in the resistance to fracture after fatigue. The total number of cycles was analyzed by using 1-way ANOVA (α=.05). A finite element analysis (FEA) was also performed. The maximum principal stress (MPS) was used as the failure criterion. ResultsThe sintered feldspathic veneer group had significantly lower fatigue resistance than sintered lithium disilicate veneer or resin-bonded lithium disilicate veneer (P<.05). The resin-bonded lithium disilicate veneer group showed significantly more fractured fragments than the other groups. No statistical difference was observed in the number of cycles. The lithium disilicate veneered groups presented similar resistance to fatigue as the monolithic specimens of the same overall dimensions. Higher peaks of MPS were observed for groups monolithic lithium disilicate, sintered lithium disilicate veneer, and sintered feldspathic veneer than for resin-bonded lithium disilicate veneer. ConclusionsVeneering a lithium disilicate substructure with a lithium disilicate veneer, bonded or sintered, increased resistance to fatigue compared with a feldspathic porcelain veneer. The lithium disilicate veneer groups had similar fatigue resistance to that of the monolithic group.

Research on the Performance of Regenerant Modified Cold Recycled Mixture with Asphalt Emulsions

In order to study the mechanical properties and effect of a regenerant on a cold recycled mixture with asphalt emulsions (CRMEs), the moisture susceptibility, high-temperature performance, low-temperature performance, dynamic mechanical properties and durability of CRMEs were analyzed and evaluated by immersion splitting strength tests, freeze-thaw splitting strength tests, rutting tests, semi-circle bending tests, uniaxial compression dynamic modulus tests and indirect tensile tests. Scanning electron microscopy (SEM) was used to analyze the micromorphology of CRMEs modified with regenerant. Finally, a comprehensive evaluation system of five different CRMEs was established based on the efficacy coefficient method to quantitatively analyze the comprehensive performance of the CRMEs. The test results showed that the regenerant can significantly improve the water immersion splitting strength, freeze-thaw splitting strength fracture energy density, and fatigue resistance of CRMEs. However, the addition of regenerant affected the high-temperature performance of the cold recycled mixture. The dynamic modulus of the CRMEs first increased and then decreased with regenerant content increasing. When the regenerant content was 8%, the dynamic modulus of the CRMEs was the highest. Adding styrene-butadiene rubber (SBR) latex can improve the high-temperature performance of CRMEs, but the moisture susceptibility, low temperature performance and fatigue resistance of the cold recycled mixture were not significantly improved, and the dynamic modulus of the mixture was reduced. Based on the efficacy coefficient method, the optimal content of regenerant is 8%. Regenerant are potential modifiers for cold recycled mixture that they can significantly improve the dynamic mechanical properties and durability.

High fatigue endurance limit of a metastable Ti-based metallic glass composite with martensitic transformation

Introducing the dendrite phase is an effective solution to overcome the low fatigue resistance of metallic glass (MG). In present study, we examined the four-point bending fatigue behavior of a new Ti50.32Zr33.92Cu4.56Ni2.12Be9.08 metallic glass composite (MGC) containing metastable dendrites. The stress-life (S–N) test and various characterization techniques including X-ray diffractometer (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) were carried out. The fatigue endurance limit, defined as the maximum stress amplitude to which the sample is subjected for 107 cycles without failure, was measured to be ~360 MPa in current MGC. Just compared to the four-point bending fatigue data in previously reported MGCs, the fatigue limit of current MGC is highest. Such excellent fatigue property results from the coupled effect of two aspects on the shear banding and fatigue damage behaviors, i.e., one is the fine separation between the dendrite phases and the other is the martensitic transformation of the metastable dendrites. These findings may improve the understanding on the fatigue mechanisms and provide a promising way for designing the MGs or MGCs with better fatigue performance.

Project-Based Learning for the Design of Progressive Dies Supporting Tools

&lt;p class="Abstract"&gt;In the oil and gas industry, manufacturing processes covered a variety of fields including pipe fittings production. Generally, this process involves a press machine utilized as a shape forming using punch-dies sets as mold profiles. The common problem found with the dies is the dimension of dies is not ergonomics to be handled manually by operators. Additionally, the support of dies tends to experience buckling upon receiving a pressure load of 15 MPa. Hence, alternative and practical designs are required, which have low deflection values and high fatigue resistance rates. Additionally, the designs are expected to be safe and economical. In this study, two alternative designs of punch-dies support are proposed. Subsequently, the FEA simulation was carried out for pipe fittings of 8 inches with ASME B16.9 standard size for WF Beam A36 Steel to compare the two proposed designs. The results show that alternative design 2 has a lower deflection value of 0.181 mm, a higher Factor of Safety of 3.21, and a higher cycle time of 358569 cycles than alternative design 1. Nevertheless, alternative design 2 has a higher production cost of 220 USD compared to alternative design 2. Therefore, this study shows that alternative design 2 has better performance while alternative design 1 is more economical.&lt;/p&gt;

Effect of mesoscale phase contrast on fatigue-delaying behavior of self-healing hydrogels.

We investigate the fatigue resistance of chemically cross-linked polyampholyte hydrogels with a hierarchical structure due to phase separation and find that the details of the structure, as characterized by SAXS, control the mechanisms of crack propagation. When gels exhibit a strong phase contrast and a low cross-linking level, the stress singularity around the crack tip is gradually eliminated with increasing fatigue cycles and this suppresses crack growth, beneficial for high fatigue resistance. On the contrary, the stress concentration persists in weakly phase-separated gels, resulting in low fatigue resistance. A material parameter, λtran, is identified, correlated to the onset of non-affine deformation of the mesophase structure in a hydrogel without crack, which governs the slow-to-fast transition in fatigue crack growth. The detailed role played by the mesoscale structure on fatigue resistance provides design principles for developing self-healing, tough, and fatigue-resistant soft materials.

Analysis of fracture damage and friction mechanical properties of silicon dioxide/polyvinylidene composites

Low tensile strength, fatigue, and friction resistance are the key factors that limit the application of PVDF in engineering. The improvement of its comprehensive mechanical properties will prolong the service life of PVDF pipe fittings and piezoelectric materials. In this article, SiO2/PVDF composites are prepared by hot pressing, the mechanical property, fatigue damage property, and friction property have been discussed. The tensile strength of PVDF prepared by hot pressing method is 46.173 MPa, which is 61.52% higher than that prepared by solution casting method. After cyclic load test, the plastic strain is decreased with increasing of content of SiO2. The wear resistance of SiO2/PVDF is best when the content of SiO2 is 4 wt%, and the mass wear rate is 1.00849 × 10−6 g/m. The mechanical properties and friction resistance of PVDF composites are improved by selecting appropriate preparation process and adding fillers.

Elasto-Plastic Deformation of Heterogeneous Metallic Materials: An Experimental Approach with AlMg4Si10

The increasing demand on thermo-mechanical strength, lightweight and formability in engineering applications require metallic materials with high sophisticated properties. Such functional alloys consist of heterogeneous composite-like microstructures, which are responsible for their stability in demanding service conditions (high temperature strength, low fatigue and creep resistance). External loads are distributed in between the phases of the alloys introducing high micro stress gradients, responsible for elastic and plastic deformation at the interfaces and micro crack initiation. Thus, the properties of such materials depend mainly on their phase shapes and 3D architectures leading to high stress gradients and elasto-plastic deformation under service conditions.This manuscript describes experimental studies on phase strain distribution for different heat treatment conditions in an AlMg4Si10 alloy. Neutron diffraction was used for strain measurement at an angle dispersive strain scanner with in-situ tensile test setup. Strain evolution under load and after unloading was measured to show elasto-plastic deformation behaviour in between the ductile α-Al matrix and stiff reinforcing Mg2Si and Si phases. The degree of plastification, its effect on micro stress gradients and its influence on crack initiation could be discussed and comparisons to other composite materials could be drawn.

Road Performance and Application Analysis of Ultra-Thin Asphalt Coating Mixture with High Elastic Modification

A kind of composite modified asphalt with high elasticity was prepared by SBS and high elasticity agent, and the asphalt mixture with easy compactness was applied. The high temperature, low temperature, water stability and fatigue properties of the mixture were evaluated by laboratory tests. The results show that the optimum content of high elasticity agent is about 6% for SBS modified asphalt. The pavement performance of the high-elasticity modified asphalt compacting mixture was improved to a certain extent. Compared with SBS modified asphalt SMA-13, the dynamic stability was increased by 13.5%. The water stability, low temperature crack resistance and fatigue resistance increased by 10.4%, 59.3% and 173%.

Laboratory evaluation of the effect of kapok fibers on the rheological and fatigue properties of bitumen

In this paper, kapok fiber (KF) was used as a bio-reinforcement material to modify virgin bitumen, and the rheological properties of the modified bitumen were studied. During the research, the fiber surface was treated utilizing silane coupling agent (KH-550), and the surface microstructure was characterized by scanning electron microscope (SEM). To observe the change of KF on the rheological properties of bitumen, rotational viscosity test, dynamic shear rheometer test, multiple stress creep recovery test, bending beam rheometer test and linear amplitude sweep test were carried out. The results indicated that KH-550 improved fiber surface roughness and strengthened the mutual bonding ability of fiber and asphalt. After adding KF, the viscosity and permanent deformation resistance of bitumen were improved. However, KF had a slight negative effect on the low temperature crack resistance and fatigue resistance in bituminous binder, the effect was relatively less on the premise of no more than 6% fiber content.

Does the type of endodontic access influence in the cyclic fatigue resistance of reciprocating instruments?

The aim of the present study was to compare the cyclic fatigue resistance of Reciproc R25 (R25) and Reciproc Blue R25 (R25B) instruments, after simulated clinical use in traditional (TradAC) and ultraconservative (UltraAC) endodonticaccess cavities. Forty mandibular molars were randomly assigned into the following groups, according to the type of access and instrument to be used: TradAC and R25, TradAC and R25B, UltraAC and R25, and UltraAC and R25B. Teeth were accessed accordingly, and the root canals were prepared using "RECIPROC ALL" kinematics. The cyclic fatigue resistance of the forty used instruments was obtained measuring the time to fracture in an artificial stainless-steel canal. Ten brand new R25 and R25B were used as control groups. The fracture surfaces and the side cutting edges of the instruments were examined with a scanning electron microscope. Data were statistically analyzed using one-way ANOVA and post hoc Tukey tests with a significance level of P < 0.05. R25B instruments showed significantly higher cyclic fatigue resistance than R25, regardless of the access cavity type (P < 0.05). No differences were observed in the cyclic fatigue resistance between instruments without simulated clinical use and used in TradAC (P > 0.05). R25 and R25B used in UltraAC showed significantly lower cyclic fatigue resistance compared with the instruments used in TradAC and without simulated clinical use (P < 0.05). R25B files showed improved cyclic fatigue resistance than R25. The use of R25B and R25 files in mandibular molars with UltraACs decreased their cyclic fatigue resistance, compared with TradAC. The use of Reciproc and Reciproc Blue files in mandibular molars with ultra-conservative endodontic accesscavities reduced their cyclic fatigue resistance. Clinicians should be aware about the reduced cyclic fatigue resistance of these files when used in mandibular molars with UltraAC, due to the synergistic effect of access angulation and severe curvature induced in the endodontic files.

Performance changes of hot recycled asphalt mixture in different layers under coupling of multiple aging factors

A climate simulation test system (CSTS) was developed to couple the aging factors including light, heat, oxygen and moisture. In the paper, 16 kinds of hot recycled asphalt mixtures modified by 3.5 wt‰ granular polymer reinforcing agent (GPR) were obtained and the pavement performances (high temperature performance, low temperature performance, water stability and fatigue resistance) of them were tested. The results indicated that the aging had a negative impact on the low temperature performance and fatigue resistance of the hot recycled asphalt mixture, especially after 30 days of long-term aging, the low temperature performance of the hot recycled asphalt mixture decreased obviously. However, the water stability of hot recycled asphalt mixture had a peak value with aging time. Besides, in the early and middle stage of long-term aging, GPR could significantly improve the pavement performances of hot recycled asphalt mixture.

Upgrading Seismic Behaviors of R/C Frames with Shaped Memory Alloys Based Braces

Intelligent systems in structural engineering are systems that are capable of automatically adapting structural behavior in response to instantaneous loads, thereby ensuring the safety of extended structural life and performance. One of the new technologies that makes it possible to achieve these goals is the production and development of smart materials. Examples of these smart materials used in structural engineering include piezo-ceramics, magnetorheological fluids, electrorheological fluids, and form-memory alloys. Shaped Memory Alloys (SMAs) are new materials that have been used in various fields of science and engineering in recent decades. In recent years, these materials attracted the attention of researchers in the field of building and earthquake engineering due to their properties such as high damping capacity, low permanent displacement and structural fatigue resistance. One of the application areas of these materials is that they are used as a brace in the structures, so the research results have shown the acceptable performance and operability of such structural systems. In this study, shape memory bracelets and steel bracelets installed as structural brackets were used as a lateral load system in the seismic improvement of concrete bending frames and factors such as residual displacement and base shear in these two load-bearing systems are compared.&amp;amp;nbsp; The model under studying is a 6-story frame that has been subjected to time history analysis. SeismoStruct software was used to analyze the model.