High Elastic Stiffness Research Articles

Inverse design of irregular architected materials with programmable stiffness based on deep learning

Incorporating biological materials-inspired irregularity into architected materials is potential to unfold a wider property or new function space, while the inverse design of irregular architected materials (IAMs) for targeted properties is still challenging, owing to the intricate structure–property bidirectional relationships. Accordingly, here, a data-driven framework is originally developed to design new irregular architected materials with programmable stiffness. In detail, a robust dataset of IAMs, which are constructed from diverse stretch- and bending-dominated building blocks, is created by a randomized strategy, and an end-to-end deep learning model is established, including a forward and an inverse network. The forward predictions reveal that IAMs exactly achieve a wide space of programmable stiffness, especially, including extremely high or low dominant elastic stiffness C11, C22 and C66. More importantly, the deep learning-driven inverse design flexibly and precisely realizes the generation of IAMs, fulfilling the customized stiffness targets. Especially, various stiffness tensors, including isotropic, orthotropic, and anisotropic types, are successfully achieved. The remarkable advantage of the inverse design is that solely through adjusting the frequency hints of building blocks, without mandatory geometrical symmetry, IAMs present the exclusive ability to hit the targeted stiffness. Overall, this work fills the gap in the inverse design of irregular architected materials with programmable stiffness and paves the way for material design via deep learning.

A Review on Slit Steel Shear Walls: Development, Implementation, and Performance

Over centuries, natural phenomena have claimed a large number of lives and caused large amounts of damage. However, they were the reason for the development of knowledge and science. In engineering, there is no doubt that earthquakes were the driving force behind many design philosophies and advanced technologies. In this regard, steel plate shear walls (SPSWs) represent one of the technologies employed in both new constructions and existing structures to bolster lateral load resistance. In addition to its high elastic stiffness and strength, SPSWs often experience significant pinching during their hysteretic response unless heavily stiffened. Thus, numerous investigations have been performed recently to enhance the seismic behavior of SPSWs during severe ground shaking. The shear walls of steel plates have been studied in various ways, including stiffened and unstiffened steel plates, low yield strength steel plates, SPSWs perforated with circular holes or vertical slits, steel walls with stiffened and unstiffened openings. A stiffened SPSW panel dissipates significantly more energy than an unstiffened panel, as well as exhibiting a ductile and stable behavior. In view of its high elongation, the SPSW with low yield point has the best damping capacity. It has been demonstrated that steel walls perforated with circular holes have improved energy dissipation, in addition to allowing utilities to pass through their openings. Vertical slits on steel plate shear walls produce an exceptionally full hysteresis loop with improved performances. Slit steel walls (SSWs) can sustain a drift of over 3% while experiencing minimal hysteresis degradation. Additionally, a frame with a SSW can endure up to 6% drift without significant damage, surpassing expected ductility levels of a special moment frame, particularly with efficient slit geometry.

The influence of pressure on the structural stability, mechanical, electronic and optical properties of TiH4 and VH4 tetrahydrides: A first-principles study

To study the high pressure behavior of metal tetrahydrides, here, we apply the first-principles method to study the influence of pressure on the structural stability, mechanical, electronic and optical properties of two TMH4 (TM = Ti and V) tetrahydrides. The calculated results show that although the formation enthalpy of two TMH4 increases with increasing pressure, two TMH4 tetrahydrides are thermodynamic stability under high pressure. In particular, the VH4 has better thermodynamic stability in comparison to TiH4 under pressure. Furthermore, the calculated elastic modulus of TMH4 increases with increasing pressure. The VH4 has strong deformation resistance and high elastic stiffness in comparison to TiH4 under pressure. Essentially, the structural stability and mechanical properties of TiH4 and VH4 are related to the formation of TM-H bond in TMH4. However, the pressure weakens the shear deformation resistance and elastic stiffness of TMH4 when the pressure is bigger than 70 GPa. In addition, two TMH4 tetrahydrides show electronic properties. In particular, the pressure enhances the electronic interaction of TiH4 and VH4 near the Fermi level, which is beneficial to store a mass of hydrogen. Finally, it is found that the pressure induces the main peak of TMH4 to occur migration from low energy region to the high energy region.

Bio-inspired facile strategy for programmable osmosis-driven shape-morphing elastomer composite structures.

Achieving programmable and reversible deformations of soft materials is a long-standing goal for various applications in soft robotics, flexible electronics and many other fields. Swelling-induced shape morphing has been intensively studied as one of the potential mechanisms. However, achieving an extremely large swelling ratio (>1000% in volume) remains challenging with existing swellable soft materials (e.g., hydrogels and water-swellable rubbers). Inspired by the shape change enabled by the osmosis-driven swelling in living organisms, herein, we report a polymer composite system composed of fine sodium chloride (NaCl) particles embedded in Ecoflex00-10 polymer. This Ecoflex00-10/NaCl polymer composite can achieve controllable volumetric swelling up to 3000% while maintaining a relatively high elastic stiffness. We demonstrate that this swellable polymer composite can serve as an active component to drive the shape morphing of various structures. By controlling the geometric design and the fraction of the NaCl particle, morphing structures capable of deforming sequentially are created. Finally, by encapsulating 3D printed polymer composite patterns using water-permeable PDMS membrane, a programmable braille with visual and tactile regulation is demonstrated for the purpose of information encryption. Our study provides a facile approach to generate customizable shape-morphing structures, aiming to broaden the range of techniques and applications for morphing devices.

Vacancy-enhanced oxidation resistance of Fe2CrAl high-temperature alloy

Although Fe2CrAl ternary alloy is a promising high temperature material, the oxidation mechanism of Fe2CrAl is unknown. To solve the problem, here, we apply the first-principles method to study the oxidized behavior of Fe2CrAl ternary alloy. In particular, the influence of vacancies on the oxidation resistance of Fe2CrAl is further studied. The calculated results shows that the oxygen prefers to occupy the octahedral interstitial (OI) site because of the interaction of O-Al, O-Cr and O-Fe atoms. It is found that these vacancies are thermodynamic stability in Fe2CrAl ternary alloy. In particular, the Cr-vacancy has better thermodynamic stability compared to the Fe-vacancy and Al-vacancy. Importantly, the Cr-vacancy has strongest the oxidation resistance because the Cr-vacancy enhances the localized hybridization between O atom and Al atom, which form the Al2O3 oxide. The formation of Al2O3 is demonstrated by the bond length of Al-O bond in Al2O3. In addition, the calculated elastic modulus of the oxidized Fe2CrAl is lower than the unoxidized Fe2CrAl whether the parent Fe2CrAl or Fe2CrAl with three vacancies. However, the Fe2CrAl with Cr-vacancy retains the high elastic stiffness compared to the Fe-vacancy and Al-vacancy. Therefore, we believe the Cr-vacancy is beneficial to improve the oxidation resistance of Fe2CrAl ternary alloy.

Influences of Ti and Mo alloying on the microstructure and properties of laser cladding for CoCrFeNi high-entropy alloys

The CoCrFeNiTi_(1-x) Mo_x high-entropy-alloy coating was prepared using a powder presetting method. The work investigated the influences of Ti and Mo addition on the microstructure and properties of CoCrFeNi high-entropy alloys. The first-principles calculation showed that CoCrFeNiTi_(1-x) Mo_x was mainly composed of the FCC phase, BCC phase, and IMCs. The coating exhibited high hardness, and the mechanical stability of the high-entropy alloys of FCC and BCC phases was maintained when x = 0.5. The coating primarily consisted of FCC, BCC, σand CoTi2 phases when x ≤ 0.75. The coating primarily consisted of FCC, BCC, σand Co2Mo3 phases when x = 1. It exhibited high microhardness, elastic modulus, elastic stiffness, and wear resistance when x = 0.5. Its average microhardness, local elastic modulus, and elastic stiffness were 873.28 HV0.5, 265.5606 GPa, and 102.8008 GPa, respectively. Besides, COF and the wear mass loss were 0.7026 mm3 and 0.0410 mm3, respectively. The coating exhibited exceptional corrosion resistance with a self-corrosion voltage of −0.700 V and a self-corrosion current of 5.387e-007 A when x = 1. The results offer practical guidance for preparing high-entropy-alloy coatings with various advantages as well as a theoretical foundation for preparing such alloys by laser cladding.

Improving the behavior of concentrically braced frame braces using a flexural damper: Experimental and numerical study

SummaryAlthough the concentrically braced frames (CBFs) systems have high lateral elastic stiffness and strength, they reflect a low seismic energy absorption capacity mainly due to their diagonal buckling under compressive loading. To overcome this problem, researchers have proposed metallic shear damper as the most popular due to its satisfactory performance and affordable cost. In this paper, an innovative metallic damper with a flexural mechanism is proposed to improve the behavior of CBF systems. It provides ease of fabrication and replacement after damage, competitive cost, and improved resistance to buckling of the CBF member. The performance of the damper was evaluated experimentally and numerically. Subsequently, two types of dampers, (a) made of rectangular flexural plates (RFP) and (b) made of I‐shaped flexural plates (IFP), were designed and evaluated. Experimental as well as numerical results indicated that both dampers provide stable and symmetrical hysteresis curves with a high energy absorption capacity. Results indicated that the IFP damper has greater stiffness (1.94–2.3 times) and ultimate strength (1.76 times) but a lower overstrength (66% less) and ductility (47% less) than the RFP damper. Moreover, design expressions were presented for the proposed damper and showed a good agreement with finite element results.

Exploring the phase stability, mechanical and thermodynamic properties of FeCrAl ternary alloy

Although FeCrAl ternary alloy is a promising high-temperature material, the structural features of the FeCrAl remains controversial. To understand the structural features and the related mechanical properties, here, we apply the first-principle method to study the structural stability, mechanical and thermodynamic properties of FeCrAl ternary alloy. Two FeCrAl phases: cubic and orthorhombic structures are designed and discussed. The calculated results show that two FeCrAl ternary alloys are thermodynamically stable at the ground state. In particular, the orthorhombic FeCrAl has better thermodynamically stable in comparison to the cubic FeCrAl. It is found that two FeCrAl ternary alloys exhibit mechanical stability based on the Born stability criteria. Importantly, we predict that two FeCrAl ternary alloys show ductility and plasticity. The orthorhombic FeCrAl shows the stronger volume deformation resistance and higher elastic stiffness in comparison to the cubic FeCrAl. Naturally, the high elastic modulus of the orthorhombic FeCrAl is related to the strong localized hybridization between Fe atom, Cr atom and Al atom in a layered structure. Finally, it is found that the calculated Debye temperature of the orthorhombic FeCrAl is higher than the cubic FeCrAl.

Cutout effects on the dynamic analysis of laminated composite plates resting on two-parameter elastic foundation

This paper investigates the free vibration analysis of cutout laminated composite plates resting on an elastic foundation of the Winkler and Pasternak type. An efficient isoparametric 9-noded Lagrangean C0 finite element method is developed based on five degrees of freedom (d.o.f) first-order shear deformation theory (FSDT), which has the benefit of the requirement of only one variable along the thickness to model the plate equations to obtain the numerical results from the formulation. The equation of motion of the plate is derived using the virtual work principle. The accuracy and efficiency of the current formulation are validated with established results concerning free vibration analysis of laminated composite plates on elastic foundations and plates containing cutouts. It is found that the results obtained using the present formulation have variation within ±1.5% of the established results. After sufficient validation of the present formulation, new parametric results are given for cutout laminated composite plates resting on elastic foundations with varying elastic foundation stiffness parameters, boundary conditions, cutouts, side-to-thickness ratios, and the aspect ratio of plate and fiber angle orientations. The impact of cutouts on the dynamic behavior of laminated composite plates is investigated, and interestingly, it is observed that cutouts alter the frequency response of plates when introduced to plates without elastic foundations or plates resting on elastic foundations having low stiffness parameters; however, when cutouts are introduced to plates with high elastic foundation stiffness, the cutouts have very negligible impact on the dynamic behavior of plates. It is observed that the layout and the pattern of the cutout in the laminated composite plate affect the dynamic behavior of plates at all elastic foundation stiffnesses.

Investigating the behavior of an innovative butterfly‐shaped damper: An experimental and numerical study

SummaryThe concentrically braced frame (CBF) suffered from low dissipating energy capacity although it pertains to a high lateral elastic stiffness and ultimate strength. To overcome the shortcoming, in this paper, an innovative damper made of two butterfly‐shaped plates installed at the end of the diagonal member of the CBF was considered experimentally and numerically. Also, the required equations were presented to design the system. In an experimental study, the damper showed stable hysteresis loops without any degradation in stiffness and strength up to a rotation of 12% (0.12 rad). This rotation capacity is 50% greater than the AISC limitation. Also, the numerical study indicated that by increasing the angle of main plates, the structural parameters are improved as ultimate strength (Fu), 47% to 90%; stiffness (K), 64% to 97%; energy absorption (E), 23% to 11%; and overstrength (Ω), 59% to 96%. By reduction of the damper's height, the parameters Fu, K, E, and Ω are increased by 47% to 76%, 23% to 64%, 49% to 93%, and 23% to 27%, respectively. Moreover, although the geometry of the damper affected the elastic stiffness, the stiffness in the nonlinear zone was independent of the geometry of the damper. Correspondingly, the slenderness limitations were suggested as 15 for height to thickness ratio and 22 for wide to thickness ratio.

An innovative shear links as dampers compound of shear plates and round HSS sections

Though concentrically braced frames pertain to high elastic stiffness and strength, their low ductility has been introduced as a no-desirable system in the high seismic risk zone. Utilizing passive energy dampers as a capable and economical idea, the shortcoming can be solved. Experimental and numerical studies on the pipe dampers confirmed their satiable performance in the case of ductility and dissipating energy capacity. But, it is suffered from low strength and stiffness. To overcome the shortcoming of these types of metallic dampers, in this paper, the strengthening of pipe damper with shear plates is proposed and investigated numerically and parametrically. Subsequently, the required equations (in good agreement with finite element results) were presented to design and predict the behavior o the damper. Results indicated that by reduction of the length to the height of the damper, the strength and stiffness are improved. Also, the ratio of the strength of the flanges to the strength of the web affects the behavior of the damper, and increasing this ratio reduces the stiffness and ultimate strength. Therefore, it is suggested that this ratio should be greater than 1.5.

Optimization of Tungsten Heavy Alloy Cutting Parameters Based on RSM and Reinforcement Dung Beetle Algorithm.

Tungsten heavy alloys (WHAs) are an extremely hard-to-machine material extensively used in demanding applications such as missile liners, aerospace, and optical molds. However, the machining of WHAs remains a challenging task as a result of their high density and elastic stiffness which lead to the deterioration of the machined surface roughness. This paper proposes a brand-new multi-objective dung beetle algorithm. It does not take the cutting parameters (i.e., cutting speed, feed rate, and depth of cut) as the optimization objects but directly optimizes cutting forces and vibration signals monitored using a multi-sensor (i.e., dynamometer and accelerometer). The cutting parameters in the WHA turning process are analyzed through the use of the response surface method (RSM) and the improved dung beetle optimization algorithm. Experimental verification shows that the algorithm has better convergence speed and optimization ability compared with similar algorithms. The optimized forces and vibration are reduced by 9.7% and 46.47%, respectively, and the surface roughness Ra of the machined surface is reduced by 18.2%. The proposed modeling and optimization algorithms are anticipated to be powerful to provide the basis for the parameter optimization in the cutting of WHAs.

Robust flexural performance and fracture behavior of TiO2 decorated densified bamboo as sustainable structural materials

High-performance, fast-growing natural materials with sustainable and functional features currently arouse significant attention. Here, facile processing, involving delignification, in situ hydrothermal synthesis of TiO2 and pressure densification, is employed to transform natural bamboo into a high-performance structural material. The resulting TiO2-decorated densified bamboo exhibits high flexural strength and elastic stiffness, with both properties more than double that of natural bamboo. Real-time acoustic emission reveals the key role of the TiO2 nanoparticles in enhancing the flexural properties. The introduction of nanoscale TiO2 is found to markedly increase the degree of oxidation and the formation of hydrogen bonds in bamboo materials, leading to extensive interfacial failure between the microfibers, a micro-fibrillation process that results in substantial energy consumption and high fracture resistance. This work furthers the strategy of the synthetic reinforcement of fast-growing natural materials, which could lead to the expanded applications of sustainable materials for high-performance structural applications.

Developing an innovative stiffened shear damper for concentrically braced frames

Although the concentrically braced frame (CBF) systems pertain high elastic stiffness and lateral strength, they reflect a low seismic energy absorption capacity. This is due to the buckling of CBF’s diagonal member under compressive loading. To overcome this, researchers have proposed the use of several types of dampers to improve the seismic behavior of the CBF systems. Among them, the metallic shear damper is the most popular due to its suitable performance characteristics. To overcome the low stiffness characteristics of shear dampers, strengthening the shear damper with X-stiffeners is proposed and the performance is evaluated numerically and parametrically in this paper. Results indicated that by adding the X-stiffeners, the ultimate strength and elastic stiffness of the shear dampers are enhanced, considerably. But, we found that the properties of the stiffeners do not impact the stiffness at rotation greater than 0.5%. The behavior of dampers is affected by some parameters such as the ratio of the strength of the web plate to the flange plate, and the ratio of the X-stiffener strength to the flange plate strength. Thus, to predict the behavior of the damper accounting for the parameters, modified equations are proposed. The results highlighted a good agreement between the proposed modifications and finite element modeling.

Experimental Investigation of Actively Confined RC Columns Using Iron-Based Shape Memory Alloy Spiral Stirrups

Shape memory alloys (SMA) can be employed as prestressing components in the form of bars and strips in new reinforced concrete (RC) members or for reinforcing existing RC constructions because of their shape memory effect. Early research focused on retrofitting concrete components with external SMA spirals, but this technology has not been extensively used in new building. Civil engineering constructions can benefit from the development of a more affordable iron-based shape memory alloy (Fe-SMA). A good form recovery stress (prestress force) and high elastic stiffness describe this Fe-SMA. As an added benefit, it is less expensive in terms of raw materials and easier to manufacture than nickel-titanium alloys (NiTi). Industrial production of Fe-SMA strips has just recently begun. In this research under an axial compression force, three circular columns are tested experimentally. The confinement of reinforcement-type steel strips and (Fe-SMA) spiral stirrups, main reinforced steel bars, as well as numerical simulation using finite elements, are all researched. The (Fe-SMA) spiral stirrups are considered strengthening techniques, internal and external confinement. Axial compressive load, load-displacement curve, and strain-reinforcement bars are all terms used to define the cause of failure. Strengthening by Fe-SMA stirrups external reinforcement maximum gains in compressive strength of around 69.99% for stirrups steel reinforcement columns and 51.64% for Fe-SMA stirrups internal reinforcement.

Performance Improvement of Innovative Shear Damper Using Diagonal Stiffeners for Concentrically Braced Frame Systems

Although concentrically braced frame (CBF) systems enjoy high elastic stiffness and lateral strength, they show a low seismic energy absorption capacity. This dilemma is due to the buckling of CBFs’ diagonal members under compressive loading. To overcome the shortcoming, researchers have proposed the use of dampers to improve the behavior of CBF systems. Among the proposed dampers, the metallic shear damper is the most popular thanks to its suitable performance as well as its economic profit. The main shortcoming of the shear dampers is low stiffness. Therefore, in this article, an innovative approach is proposed to improve the behavior of the shear dampers. Subsequently, strengthening the shear damper with X-stiffeners is proposed, and its behavior is evaluated numerically and parametrically. Results indicate that by adding the X-stiffeners, the ultimate strength and elastic stiffness of the shear dampers are enhanced considerably. However, the properties of the stiffeners do not impact the stiffness in the nonlinear zone. Moreover, the behavior of the dampers is affected by parameters such as the ratio of the strength of the web plate to the flange plates, the ratio of the X-stiffeners to the flange plates, and the ρ factor. To consider the parameters to predict the behavior of the damper, required equations are proposed which demonstrate a good agreement with finite element results.

Synthesis, Crystal Structures, Mechanical Properties, and Formation Mechanisms of Cubic Tungsten Nitrides

Cubic tungsten nitrides with high elastic stiffness are promising replacements for metal carbides used in tool applications to achieve enhanced working efficiency. However, due to the difficulties in preparing these nitrides at ambient pressure, their crystal structures and mechanical properties remain largely elusive, which have limited the functionality of these materials. Here, we report a comprehensive study of cubic tungsten nitrides synthesized by a high-pressure method, leading to definitive structural identifications of rocksalt cF8-WN and NbO-type cP6-WN involving atomic deficiencies. Combined with calculations, we find that the structural stabilities of both nitrides are closely related to the atomic deficiency that prevents the filling of unfavorable W: 5d-t2g bands. The disordered N vacancies are decisive for stabilizing cF8-WN, while the ordering of W and N vacancies occurs at 3 GPa and relatively low temperatures and leads to the formation of nearly stoichiometric cP6-WN, rather than previously misassigned cP7-W3N4. Both nitrides exhibit similar excellent mechanical and thermal properties, rivaling and even exceeding WC. Besides, their formation mechanisms are also explored to be associated with atomic vacancies, shedding light on the rational design of functional nitrides by defect chemistry.

Piezoelectric properties in two-dimensional GeC and its surface functionalization by chlorination, fluorination, and chloro-fluorination

In this work, the stability, mechanical, and piezoelectric properties of GeC monolayer and its alteration in halogenated GeC monolayers were investigated by density functional theory. The elastic parameters of GeC monolayer were reduced after halogenation, indicating the higher rigidity of the pure GeC monolayer in comparison to the halogenated ones. The relaxed-ion calculations revealed that the F-GeC-Cl and Cl-GeC-Cl configurations have the higher elastic stiffness, and higher e11 compared with the Cl-GeC-F and F-GeC-F. The Hirshfeld charge analysis showed that the difference value between the charge of carbon atoms and the charge of halogen atoms are higher in Cl-GeC-F and F-GeC-F monolayers showing the electrons are more distributed around the halogen than the C atoms, and leading to the lower e11. The d11 follows a similar pattern to e11 whereas the e31 and d31 almost follow the reverse pattern compared to the e11 and d11, and are almost larger when the electron is more distributed around the halogen atoms.

Numerical evaluation on collapse-resistant performance of steel-braced concentric frames

Steel-braced concentric frames (SBCFs) are a popular form of structure and has been widely employed in seismic regions owing to their high strength and elastic stiffness; however, the effects of key parameters on the collapse behavior of SBCFs are unclear due to insufficient investigations, which should be further explored in column removal scenarios. To this end, numerical models were employed to explore the key parameters affecting the collapse behavior of SBCFs in this study. The numerical models of steel frames with or without braces were validated based on previous experimental results. According to the refined model, the effects of brace members of various types and with different slenderness ratios on the collapse behavior were illustrated. The results showed that an X brace type with smaller slenderness ratio is the most appropriate for enhancing robustness against progressive collapse. Thereafter, full-scale numerical models were established to investigate the effect of the column removal position, and the results showed that the frame relied purely on flexural action in a side column loss. Moreover, the effect of the position of horizontal brace layers on the collapse behavior was investigated in the middle and side column removal scenarios. To gain deeper insight into the load-resisting mechanisms, the specific contributions to the total resistance of different mechanisms in different stories, bare steel frames and braces, and tensile and compressive braces were separated. Finally, a strategy for the robustness enhancement of high-rise steel frames was empirically proposed, and it was suggested that the provision of a brace layer for approximately every 10 stories would be effective for the anti-collapse design of high-rise buildings.

Comparison of thermal performance of steel moment and eccentrically braced frames

Eccentrically braced frames (EBFs) are typically employed in seismic design because they integrate the benefits of concentrically braced frames and moment-resisting frames, providing both high elastic stiffness and high ductility. However, the effect of fire on the structural stability of EBFs has not been well documented. Object-oriented techniques used in software program development have become popular in recent years, primarily because of their ability in addressing various complexity issues. Software developed based on an object-oriented approach is more robust than conventional software. Using the abovementioned approach, additional codes can be incorporated, thereby simplifying testing, refining, maintenance, and software extension. Furthermore, the object-oriented approach can be used for finite element analysis. This paper presents the further development of OpenSees software with the inclusion of other parameters: thermal parallel material, thermal spring element, thermal spring section, as well as beam with hinges and thermal elements subjected to fire loading. In contrast to the routine creation of fire-specific applications, these modifications improve the existing finite-element codes, thereby facilitating multi-hazard analysis (e.g., post-earthquake fire). OpenSees is considered in this study as it is an open-source application and suitable for object-oriented design. The abovementioned elements, particularly spring elements, are used extensively in structural simulations (e.g., the modeling of a link beam in an EBF); however, owing to the lack of thermal functions for these elements in OpenSees, the thermal performance of structures that involve these elements cannot be evaluated. Herein, the aforementioned new elements are introduced for the first time; furthermore, the behavior of an EBF system is investigated under thermal loads using open-source software. The thermal performance of EBFs subjected to realistic fire is evaluated in this study based on an analytical modeling of a three-story building. Finally, several compartment fire scenarios are simulated for both EBFs and gravity framing bays. Results show that the EBFs improve the fire performance of the system by extending the time to collapse.