فهرست مطالب احمد ملکی

Philosophers, using their unique philosophical terminologies and language, have presented strong proofs for establishing the existence of the Almighty God. On the other hand, arguments for proving the existence of God can also be presented from the verses of the Quran. But is it possible to derive these philosophical proofs from the Quranic verses, and even claim that philosophers have derived their proofs from the revealed source? This research aims to provide an affirmative answer to this question by using the rational principles of logic to derive and elucidate the premises of certain proofs for God's existence in the Quran. The following will be illustrated: (1) rationality of the concepts in this holy book; (2) the inseparability of the Quran and logical reasoning; (3) an aspect of Qur’anic scientific miraculousness. The present study, using a descriptive-analytical method, examines two philosophical arguments for establishing God's existence in historical order: the argument of contingency and necessity, and the argument of existential indigence. The philosophers have extracted the first argument from verse 35 of Surah At-Ṭūr and the second argument from verse 15 of Surah Fāṭir.

Abstract Considering that Faraja can be successful in order to deal with drug crimes by adopting appropriate policies and strategies in the field of management, for this reason, the purpose of the present research is to analyze the performance of police disciplinary measures in dealing with drug crimes.This research is among applied researches and in terms of descriptive-analytical methodology, it was done on a mixed basis. The statistical population in the qualitative and quantitative part of the present research consists of commanders, managers, deputies, heads of departments and external organizations involved in the fight against drugs. Also, spss25 software was used for data analysis. In this research, the performance components of police disciplinary actions in dealing with drug crimes were investigated.Based on the results, it can be concluded that the difference between the ranks is significant. Among the policing measures, "sealing and destroying places and hangouts of drug use" had the most impact on the performance of policing measures of the police in dealing with drug crimes. Conclusion Analyzing the performance of law enforcement measures in dealing with drug crimes in the current situation where society's demands are increasing day by day, is very important and fundamental, and it is necessary to organize and modify executive action planning and in the field of increasing drug detections. in North Khorasan province to provide a suitable platform to achieve this goal.

The argument of the righteous is intended to demonstrate the existence of Almighty Truth without the mediation of creatures. Fārābī propounded this approach, and Ibn Sīnā actualized it through interpreting the argument of ‘possibility and necessity’. Mullā Ṣadrā objected to its being righteous in Ibn Sīnā’s reading and presented an argument based on the same method. Now, the question is whether this argument, which is the result of the efforts of some distinguished Islamic philosophers, from Fārābī to Mullā Ṣadrā, can be logically inferred from the Holy Qur’ān and, thus, claim that this holy Book expressed this truth many centuries before all of them. Following a descriptive-analytic method and through employing logical principles, this study has discovered and inferred this argument from verse 53 of al-Fuṣṣilat Chapter. Moreover, through explaining the major and minor propositions of the argument, it has revealed how each of them can be inferred from this verse. The findings of this study indicate the rationality of Qur’anic concepts, manifest the inseparability of the Qur’ān and this argument objectively and based on proof, and introduces one aspect of the scientific miracle of this Heavenly Book.

This research investigates the behavior and failure mechanisms of steel beam connections to reinforced concrete columns using Buckling-Restrained Steel Plates (BRSP). These connections, as one of the most critical components of composite steel and concrete structures, play a vital role in force transfer and resistance to various loads, particularly dynamic loads such as earthquakes. The primary objective of this study is to analyze and enhance the performance of these types of connections under cyclic loading using numerical analyses. In this research, various parametric models were used to examine the impact of BRSP thickness on the hysteresis behavior and load-bearing capacity of the connections. Different BRSP thicknesses ranging from 5 to 25 mm were considered, and their effects on stress distribution and failure mechanisms were analyzed. The results of the parametric studies indicate that increasing the BRSP thickness improves stress distribution in the joint area of the concrete column and the beam-to-column connection. This improvement includes reducing stress concentration and increasing stress distribution uniformity, which can lead to a reduction in local failures and an overall increase in connection stability. In numerical simulation models, the use of BRSPs has created wider and more stable hysteresis loops, indicating increased energy absorption capacity and improved deformation behavior of the connections under cyclic loading. Failure modes were also comprehensively examined in this study. The results show that BRSPs can reduce the concentration of failures, increase bending resistance, and prevent buckling in steel beams. These findings highlight the importance of using BRSPs in enhancing structural performance and reducing potential failures under severe loading conditions. These results can serve as a foundation for further research in improving structural connections and developing innovative techniques to enhance the stability and durability of structures. Additionally, the findings of this research can serve as a guide for engineers in designing and implementing earthquake-resistant structures.

Considering the increasing use of seismic isolators in the country, which reduce the force on structural members and increase the overall displacement of the structure during an earthquake, it is necessary to create an optimal method for using this system along with reducing the overall displacement of the structure. Also, the use of damper systems reduces the overall and inter-floor movement of the structure during an earthquake. Therefore, it is essential to investigate the effect of using damping systems to optimize seismic isolators. On the other hand, the optimal use of the combination of two damper and isolator systems can be effective in reducing construction costs and repair costs resulting from earthquakes and provides structures with optimal performance. Therefore, in this article, two viscous and frictional dampers as well as isolator were used in high-rise concrete structures with 15 and 20 floors and the combination of these two systems was evaluated in the behavior of the structure. The structures are separated by lead core rubber isolators. The results were studied under three earthquake records of the nearby area. The results showed the positive effect of dampers and separators on the behavior of the structure, and reasonable results were obtained depending on the seismic records used in the article. also, showed the positive effect of the combination of separators and dampers in reducing the amount of relative displacement, roof displacement and base shear. The simultaneous use of damper and isolator in the structures caused a 35% reduction in the base shear of the structures, 47% in the maximum relative displacement and 29% in the displacement of the roof point.

The conflict between science and religion has its roots in the West, especially following the Renaissance, and it gradually spread to the East and became the focus of Muslim scholars. In this respect, Allameh Hassanzadeh Amoli, relying on the comprehensive tradition of Islamic thought, attempted to explain the relationship between the two. The current research, thus, aims to explore the relationship between science and religion from his perspective. According to the results, giving originality to the aspect of the discovery of science in his definition of science, Allameh regarded it inappropriate to restrict and reduce science to mere empirical sciences; in contrast, while acknowledging Islam as the religion of truth, he saw religion as a divine legislation based on the creational secrets of the creation that is drawn up for the eternal happiness of man; and, finally, in explaining the relationship between science and religion, he presented the assistance theory in the fields of empirical sciences, mathematics, philosophy, and mysticism.

The holy Quran is, First of all, the most comprehensive book for the eternal happiness of man. Secondly, it is the revealed form of God's unlimited knowledge is in the form of words and phrases; Thirdly, it is a book of arguments and proofs to the extent that it has more than three hundred times called for reasoning and even demanded proofs from its opponents. However, some commentators such as Allameh Tabatabaei believe that this divine book has not provided any proof to prove the existence of God - which is considered the basis of monotheism and happiness and the pillar of all religions. Many contemporary commentators of Quran have opposed this theory and say that on the assumption that the verses of the Qur'an did not directly prove the existence of God, it is not the case that such proofs cannot be deduced from the inner layers of the verses. Therefore, using the logical rules in discovering implicit syllogisms, applicating the descriptive-analytical method, ignoring the theoretical issues raised in this regard, and presenting an objective and exemplary form, according to the rule of "proofs of the possibility of something happening", the present study seeks to prove that the philosophical proofs such as "possibility and necessity" can be inferred from the verse 65/ 59, the "proof of Sediqeen" from the verse 25/ 45, and also the "proof of order" - which is considered a verbal argument – from the verse 20/ 50. So, this study wants to say that the root of these proofs can be find in verses of this heavenly book. Conducting researches like this can be count as a manifestation of the inseparable relation between the Qur'an and proofs and, someway, shows a view of the scientific miracle of this divine book.

Siddiqui's argument is proof of the existence of God without the mediation of creatures. Al-Farabi proposed this method and Ibn Sina claimed to have established this argument by presenting the proof of "possibility and obligation", which was objected to by Mullah Sadra, and finally, Mullah Sadra himself and after him, Allameh Tabataba'i, each presented a new version. They presented this proof. Hazrat Ayatollah Javadi Amoli, on the one hand, in argumentative debates, has disputed with the same criteria that Mulla Sadra disputed in Ibn Sina's argument of being a Siddiqui, in Mulla Sadra's argument itself, and finally emphasizes the argument of Allameh Tabataba'i, and on the other hand, in arguments Tafsir has discussed the Qur'anic evidence on this argument. This research, with descriptive and analytical method, aims to answer this question: How is the explanation of Siddikin's argument and its Quranic evidence from the perspective of Ayatollah Javadi Amoli? As a response, after the presentation of Siddikin's argument from the point of view of Ayatollah Javadi Amoli, he has endeavored to explain its Quranic evidence with regard to verse 45 of Surah Furqan and 53 of Surah Al-Fazlat and to explain the testimony and implications of each of the verses on the claim, so that Firstly, it is an example of the rationality of the concepts of the Quran, secondly, it is a manifestation of the inseparability of the Quran and proof in an objective and exemplary manner, and thirdly, it shows an aspect of the scientific miracle of this divine book.

Social health is one of the most basic health indicators of any country and can be affected by various factors. Therefore, the present study was conducted with the aim of investigating the mediating role of religious coping in the relationship between psychological toughness and social health of nurses.

The research method was descriptive-analytic correlation type. The statistical population was all nurses working in Emam Hassan Mojtaba Hospital in Karaj during the first three months of 2022. Using randomized sampling, 100 of them were selected as samples. They started studying. Data were collected using Keyes social health questionnaires (2004), psychological hardiness by Kiamrai et al. (2017) and religious coping by Pargament et al. 24 versions were analyzed.

The results showed that there is a positive and significant correlation between psychological hardiness (r = 0.433) and religious coping (r = 0.433) with social health (p <0.01). Also, the structural model of social health based on psychological hardiness by religious confession was fit.

The results showed that religious coping has a mediating role in the relationship between psychological hardiness and social health. Therefore, the results of the study show the importance of psychological hardiness and religious coping in social health of nurses.

In the present study, the cyclic behavior of steel plate shear wall of a three-story steel frame equipped with added damping and stiffness (ADAS) dampers was evaluated. In this study, with the aim of investigating and improving the performance of the steel plate shear wall against lateral forces, the proposed dampers were applied in the distance between the columns and the steel plate shear wall infill plates. The parameters studied include the thickness of the damper sheet (8, 10, 12, 14 and 16 mm) and the thickness of the infill plate (3, 4, 5 and 6 mm) respectively. Evaluation of cyclic behavior of steel plate shear wall was performed using finite element method via ABAQUS software and the loading protocol based on ATC-24 was applied. In order to verify, the experimental specimen was simulated by ABAQUS software and it was observed that the experimental specimen and the finite element model are in good conformation and the finite element model can be applied to study and compare the parameters considered in this study such as energy dissipation, strength, stiffness and ductility. The results showed that as the thickness of the damper sheet increased, the energy consumption in the steel plate shear wall system increased from 12 to 66 percent compared to the model without dampers. Also, by reducing and increasing the thickness of the infill plates in the second and third floors compared to the model without dampers, we saw an increase in energy consumption from 52 to 64 percent compared to the model without dampers, which indicates the good performance of the dampers. The strength of the steel plate shear wall system increased from 2.40 to 3.14 times by considering different thicknesses for the damper compared to the model without damper, and further by considering the infill plates for the steel plate shear wall system. We saw an increase in strength from 2.30 to 2.81 times compare to the model without damper. The stiffness level of each steel plate shear wall model was investigated and compared, and we saw an increase in stiffness from 76 to 99 percent compared to the model without damper. Also, considering the thickness of different infill plates for the steel plate shear wall system, the stiffness increased from 82 to 98 percent compared to the model without damper. As the thickness of the damper sheets increased, the ductility increased from 2.32 to 2.55 times compare to the model without damper. Also, considering the thickness of different infill plates for the steel plate shear wall system, we saw an increase in strength from 2.29 to 2.55 times compare to the model without damper. Further, by examining the hysteresis curves and the hysteresis damping ratio of different models, it was evident that the models equipped with dampers are significantly superior to the models without dampers, and as the thickness of the dampers increased, the area under the curve of each model increased. As a result, the larger this level is, it indicates that the member is more malleable and has the ability to absorb more energy. Finally, the performance of the proposed dampers was investigated along with the damper failure mechanism. The results showed that ADAS dampers with their special deformations, significantly increase energy consumption and make the steel plate shear wall more malleable and by absorbing a large amount of energy they reduced the force applied to the main components and prevented the destruction of the steel plate shear wall.

The use of steel beam connection system to reinforced concrete columns has been used as an alternative to steel bending frames in medium and high-rise buildings. In high-rise buildings, because the rigidity of the structure controls the design, the use of concrete columns with more rigidity compared to steel columns makes the design economical. In this study, the seismic behavior and energy-dissipation of steel beam to reinforced concrete column connection with double-skin steel tubular are investigated using numerical methods. This system improves the hysteresis behavior and performance of traditional steel beams to reinforced concrete column connection. To evaluate the steel beam's hysteresis behavior and energy absorption to reinforced concrete column connection with double-skin steel tubular system, parametric studies were performed. Parametric studies have been performed applying the nonlinear finite element (MFE) procedure to investigate the improved models. The parametric studies comprise examining the parameters of thickness and cross-section shape of an inner tube. Also, the accuracy of finite element models was evaluated by comparing test results that showed the good accuracy of finite element models in predicting the specimens' hysteresis behavior and failure modes. The results indicated that the thickness of the inner tube of improved models has a considerable influence on determining the ultimate capacity, performance, and energy dissipation. Also, the results show that the details of the construction of the internal tube were a considerable effect on the performance and hysteresis behavior of steel beam to reinforced concrete column connection with double-skin steel tubular.

Composite steel sheet shear wall (CSPSW) is a relatively new structural system that has been proposed to improve the performance of steel sheet shear walls by adding one or two layers of concrete wall to the filler plate. In addition, the buckling of the filler steel sheet has a significant negative effect on the shear strength and energy dissipation capacity of general systems. Accordingly, in this study, using the finite element method (FE), the performance and behavior of composite steel shear walls using T-shaped hardeners to prevent buckling of the filler steel sheet and increase the capacity of the CSPSW system have been investigated. In this paper, after modeling the shear walls of composite steel sheets with finite element methods and calibrating the models with experimental results, the effect of parameters such as the type of hardener including vertical, horizontal, diagonal and a combination of T-shaped stiffeners and its effect On the final capacity, the buckling of the sheet plates, the von Mises stress and the failure states have been investigated. The results show that the arrangement of vertical and horizontal stiffeners does not have a significant effect on the capacity and performance of CSPSW. Also, the use of vertical or horizontal stiffeners does not significantly affect the capacity and performance of CSPSW. On the other hand, the use of diagonal hardeners potentially affects the performance of CSPSW and increases the capacity of steel shear walls by up to 25%.

The use of displacement-dependent steel curved dampers as fuse or interchangeable element in the beam-to-column connection region is one of the newest methods for improving the seismic performance of semi-rigid moment steel frames (SRMF). In the present study, performance of low-yield strength steel curved dampers in SRMF has been investigated. These dampers are inactive and install in the beam-to-column connection region. Variable parameters of this study involve the damper width (75, 100 and 125 mm), damper thickness (10, 15, 20, 25 and 30 mm) and the curve damper steel type (SN400YB and LY160). Evaluation of SRMF models were performed using finite element method by ABAQUS software. For validation, a SRMF with steel curve dampers under cyclic loading was modeled that had been experimentally tested and reported in previous experimental research and a good agreement was observed. The results show that the use of low-yield strength steel in curved steel dampers, depending on the damper thickness, can lead to an increase in the ductility parameter and total energy dissipated compared to the steel with higher yield stress. Also, the steel curved damper around the beam-to-column connection zone has caused the plastic hinge to occur in the farther region of the connection.

Reinforced concrete structures with standard steel rebar are vulnerable to corrosion and harsh environmental conditions, hence RC structures reinforced with fiber-reinforced polymer (FRP) rebar were commonly used these days. Du to FRP rebar’s better performance such as high strength, low self-weight, electromagnetic transparency and, as mentioned, non-corrodibility nature, using them as reinforcing bar is very widespread now. Because of financial matters, between different kinds of FRPs, GFRP is a better choice. Considering GFRP’s high strength and elastic behavior until failure, Although a large amount of reinforcement ratio is needed in composite beam components, the flexural stiffness of GFRP rebar reinforced beams is relatively lower compared to steel-RC, and more deflection and cracking are allowed in the serviceability design of these beams. Recently, shear and flexural behavior of continuous concrete beams reinforced with GFRP bars has been well investigated. Because of linear elastic behavior of GFRP materials until failure, considering moment redistribution in analysis and design of these beams is not allowed in almost all of cods and guidelines. Although many experimental and numerical researches investigated the moment redistribution in FRP-RC continuous beams with rectangular section, the behavior of these beams with T-section is almost unknown. This paper is a numerical investigation of existence and variety of moment redistribution in concrete continuous T-section beams reinforced with GFRP bars using finite element method with ABAQUS software. The verification of numerical models was done with some experimental beams, so the simulation can be used for further researches. The considering variables included the longitudinal reinforcement percentage, the number of main bars with constant bar ratio, transverse reinforcement ratio, stirrup space with constant ratio and constant bar size. For investigating mentioned parameters, 35 beams were modeled in software according to Canadian design and construction of building structures with FRP code, so 5 groups of beams were made which one beam is constant in each group. T-section beams were modeled assuming which failure happens because of concrete crashing not rebar failure. Deflection and serviceability were not interested, so bond-slippage behavior of GFRP rebar with concrete is not considered in modeling. Problem is indeterminate, so the percentage of moment redistribution was determined by comparing the reactions resulted from numerical and elastic analysis. Load-deflection and load-moment redistribution curves were used to discuss. The results show, as there is in steel-RC structures, moment redistribution exist in GFRP-RC continuous beams with T-section; however the amount of it is lower. Amount of bars between 2.5 times of balance reinforcement ratio and 3.5 times of it, in top and bottom of beam, shows the highest flexibility load and moment redistribution capacity. Increasing the number of main bars with constant reinforcement ratio and increasing the stirrup space with constant transverse reinforcement ratio reduce the moment redistribution capacity. It seems that the minimum amount of transverse reinforcement considered in Canadian code is not enough for preventing shear failure in these beams. So, with considering some points, the moment redistribution can be taken to account in analysis and design of GFRP-RC continuous beams with T-section.

The purpose of this study was to obtain the base shear force and an overturning moment of the marine jacket in the face of accidental sea waves and the use of a rhombus-shaped wave barrier in front of the jacket’s structure with the aim of reducing the force and overturning moment. In this regard, the model of the jacket structure is constructed at a height of 4.55 meters, 402 meters in length and 4 meters in depth of water, exposed to random waves of the sea and is subjected to the Jonswap spectrum in the flume of Fars National Marine Laboratory (NIMALA). A floating wave barrier was placed in the front of the jacket, and random waves with a wavelength of 23 centimeters were shifted to the jacket. The results show that the wave barrier was caused the reduction of base shear, in maximized, effective and average waves, respectively, 20.56, 34.29 and 27.77 percentage, and 34.31, 33.11 and 46.36% subsequently of the overturning moment. In all examinations, deep water conditions prevail.

Reinforced concrete with steel fibers has been widely used in concrete and reinforced concrete structures in order to improve the properties of concrete. The reason for this widespread use is the myriad technical and economic benefits of using steel fibers in a concrete body. Due to these important advantages in concrete properties, the production and application of steel fibers in the industrialized countries of the world has a wide range, so that currently various types of steel fibers with various technical specifications and applications are mass-produced industrially. Reinforced concrete with steel fibers includes a concrete body composed of cement, stone materials, water as well as a percentage of short steel fibers that are mixed in a completely randomly and in different directions in the mixture that the presence of steel fibers determine the characteristics of concrete compared to pure Improves. Determining the optimal percentage of fibers is one of the important factors in terms of economics and efficiency of concrete. In this study, to determine the percentage of optimal fibers in different strength classes, 24 mixing designs were prepared and a mechanical laboratory and fresh concrete were performed. The flexural strength of samples containing 0.9% of steel fibers for categories C40, C50 and C60 was 1.91, 3.86 and 5.14 times higher than the control sample, respectively.

The jacket-type platform is the most common offshore structure employed for the oil and gas production from the reservoirs below the seabed. It consists of three main parts: superstructure or topside, substructure or jacket, and the foundation or piles. Construction of floating breakwaters and wave barriers is one of the commonly used methods for the protection of harbors and coastal structures. However, their application for the protection of offshore structures has not been extensively studied. The present paper investigates the effects of a floating wave barrier installed in front of an offshore jacket structure on the wave height, wave-induced forces, and consequently jacket’s base shear and overturning moment.Abul-Azm and Gesraha (2000) studied the hydrodynamics of floating pontoons under oblique waves. Gesraha (2006) analyzed the shaped floating breakwater in oblique waves. Rahman et al. (2006) presented a numerical modeling for the estimation of dynamic responses and mooring forces of submerged floating breakwaters. Christensen et al. (2018) conducted a set of experimental and numerical studies on floating breakwaters. Dong et al. (2008) carried out a number of experiments on the wave transmission coefficients of floating breakwaters.In the present research, a jacket model with the height of 4.55m was fabricated and tested in wave flume of NIMALA marine laboratory. The wave flume was 402m long. The jacket was tested at the water depth of 4m subjected to JONSWAP waves with the height of 20cm, 23cm, and 28cm. The mechanism of wave energy dissipation due to hitting a wave barrier is mainly a combination of the wave diffraction and the wave reflection. A square cross section was selected for the wave barrier. Results showed that a floating wave barrier can effectively reduce the base shear and overturning moment in an offshore jacket structure.

Addiction is a psychosocial disease that causes the psychological and physiological dependence of a person suffering from these substances. The purpose of this study is to identify some factors that influence the return of drug addicts to drug abuse centers in North Khorasan province. The current research is a descriptive study in which 70 addicts referred to addiction treatment centers were selected by random sampling, the data collection tool included a questionnaire consisting of two parts: the first part (demographic information containing 9 questions) and the second part (Effective factors in substance addiction which includes individual, family-environmental and social factors which contains 18 questions) and finally the data was analyzed by SPSS software. The findings of this research show that According to individual characteristics, most of the studied subjects were aged 19-24 years. The majority of these people had below diploma education, married, unemployed and in contact with addicted and deviant friends, and also the most effective factors in drug addiction include curiosity during adolescence (individual reasons), children of divorce (family reasons), the existence of a supervisory atmosphere. Poor in school and university (environmental causes) and demeaning addicts by society (social causes) can be mentioned. According to the obtained results, it can be said that a set of personal, family, environmental and social factors, etc., causes relapse to addiction.

In the present paper, the behavior of eccentric braced steel frames with thin infill plates is investigated. The main purpose is to provide a new form of eccentric bracing, which improves the seismic behavior by adding a thin steel plate under the link beam. In the proposed model, due to the increase in frame stiffness, flexural stiffness and shear of the beam in the bracing frame will not respond to the forces. Therefore, in order to provide the required stiffness and ductility of the frame, it is suggested to use a steel plate under the link beam connected to the bracing connection plates. In the proposed models, two groups of models with steel plate under the link beam (middle steel plate) have been studied. In the first and second groups, all analysis are of static type, taking into account the geometric nonlinear effects in an eccentric frame with infill plates, the height of the plate under the link beam (middle steel plate) is 460 and 742 mm, respectively. The studied parameters include the height of the middle plate, the thickness of the middle plate and the effect of the arrangement of stiffeners on the performance of the frame. For numerical analysis of the models, the finite element method using Abaqus finite element software with increasing load has been used. Extraction results in the models include force-displacement curve, stiffness decay, amount of wall out of plane displacement due to buckling, inelastic dissipation energy and stress distribution in the structure (stress contour). According to the results of numerical models, the middle steel plate is very important in providing ductility and increasing the strength of the structure. Also, with increasing the height of the middle plate, the development of the diagonal tensile field into the infill plate increases, so local buckling can be converted into general buckling in the infill plates. Among the arrangements of stiffeners, it was observed that the stiffener under the middle plate has the least effect on increasing the force-displacement response of the structure. By evaluation of models with a middle plate with a height of 460 mm and two vertical stiffeners, compared to the model with four stiffeners, the structural capacity (force-displacement) has increased by about 31%. By evaluating the models with a middle plate height of 760 mm, it can be found that the use of stiffeners with different geometric arrangements do not have a major effect on increasing the stiffness in the elastic and inelastic stages, prevent the sudden decrease in stiffness in models without stiffeners due to buckling observed at the junction of the brace to the middle plate. Also, the free edge stiffener of the middle plate has practically no effect on the sudden decrease in stiffness, but on the other hand, vertical stiffeners or a combination of horizontal and vertical stiffeners have performed well in terms of preventing a sudden decrease in structural stiffness. The thickness of the steel plate has a significant effect on increasing the strength and reducing the local buckling in the middle plate. Local buckling was observed at the junction of the middle plate to the brace, which is recommended to use stiffeners for the middle steel to reduce the effects of local buckling of the plate and to prevent a sudden decrease in strength and stiffness. In steel plates with shear behavior that do not allow the complete formation of diagonal tensile fields, stiffeners prevent a sudden decrease in strength but do not have a significant effect on increasing the overall stiffness of the structure.

The authors regretted the typographical error and requested a change in the second author's academic rank from "Associate Professor" to "Assistant Professor", which was applied in this amendment. It should be noted that the Journal of Science and Technology of Composites has no responsibility for the subsequent consequences of this amendment, and this has been done based on the written request of the authors, and they are responsible for any subsequent problems.

The main purpose of this study is to develop a finite element model to study the effect of steel-shaped fibers on the flexural strength of ultra-high performance fiber concrete. For this purpose, in order to numerically simulate, a multi-scale finite element model was developed in which concrete was modeled as a homogeneous and uniform material and steel fibers were randomly distributed inside it. In order to make more realistic assumptions, the area of ​​adhesion between the fibers and the concrete is also considered. After validating the results of finite element model with the results of experimental tests, the effect of parameters such as volume fraction and adhesion of steel fibers on the strength characteristics of flexural strength of ultra-high performance concrete reinforced with fibers has been studied numerically. The results indicate that the effect of using fibers on the amount of energy absorption by fiber reinforced concrete is much greater than its effect on other characteristics of this type of concrete and especially the use of fibers in low fiber volumes has a very significant effect on energy absorption so that for 0.5% of the volume fraction of steel fibers, an increase of about 17 times compared to the sample of super-reinforced concrete without fibers can be resulted

Rotational friction dampers are a specific type of friction dampers which have several advantages. Dampers are used to improve the cyclic behavior of structures against forces caused by wind and earthquake. These types of dampers will cause energy dissipation by its rotating and rerotating. However, complete and comprehensive researches have not been performed on the effect of rotational friction dampers and their effect on the bearing capacity of steel frames. In this research, the behavior of concrete-filled steel tube (CFT)  in two cases frame braced with rotational friction dampers and frame braced without rotational friction dampers is investigated. For verification, the results obtained from finite element method software, ABAQUS, were compared with that of experimental studies for test samples used in a building with a height of 300m in Osaka, Japan. The hysteresis curves of the modeled samples are in good agreement with the experimental results. In order to investigate the performance of steel composite frame (with CFTs) braced with rotational friction dampers towards to steel composite frame (with CFTs) braced without rotational friction dampers  under the effect of three earthquake Far-field records, the structure was modeled, designed and analyzed in ETABS software. The use of bracing with rotational friction dampers has caused a decrease in the displacement of the roof’s center of mass for each record mentioned above which modeled in ETABS software. It decreased by 13 to 49 % for 9 records and increased by 2 to 17 % for 2 records. The use of bracing along with rotational friction damper modeled in ABAQUS software under the effect of each record has caused a decrease in base shear. The extent of these reductions was different for each record mentioned above. In each record modeled in ETABS software, the base shear of the structure has not reduced similarly; however, in some cases, the base shear has increased. It had a decrease of 11 to 37% for 7 records and an increase of 3 to 26% for 4 records.  Then a Single-storey frame with single-span With the same materials and specifications introduced in ETABS software in ABAQUS software Has been modeled. For lateral loading of columns, the lateral loading protocol based on ATC-24 and the instructions for using dampers in the design and reinforcement of buildings have been used.  According to Regulation No. 766 of the Program and Budget Organization, the loading cycles introduced in ETABS software with a frequency of 1.15T have been used in the ABAQUS Limited Components Software to move. The use of rotary braces and crankshafts in the ABAQUS limited component software under the influence of each of the discussed records has reduced the displacement of the structure relative to the structure without braces and without rotational friction dampers of the structure mentioned above was exerted under the record effect of the same earthquake in ABAQUS software The use of bracing along with rotational friction damper modeled in ABAQUS software under the effect of each record has caused a decrease in base shear. The amount of energy reduction for records understudy was not equal and varied from 8% to 34.7%. The hysteresis curves of base shear of braced structures with and without dampers are well presented.