Nowadays, optimization meta-heuristic algorithms are used in different fields of science, includi... more Nowadays, optimization meta-heuristic algorithms are used in different fields of science, including a computer, mechanics and civil engineering. The algorithms are inspired by the laws governing nature, such as the principle of physics, an association of animals or finding and hunting food by animals. Using the smell sense of a bee insect, called Smell Bees Optimization (SBO), the present paper proposes an optimization algorithm that is meta-heuristic and inspired by nature. To verify and validate, the proposed algorithm, benchmark functions and engineering design examples were applied, which were previously optimized using different algorithms. In doing so, such as a cantilever beam, pressure vessel, three-bar truss, tension/ compression spring and a welded beam were applied, which were previously optimized using different algorithms. In order to run programming, MATLAB was used. The results obtained by SBO are compared to the previous algorithms, optimized solutions of engineering examples are improved, and the target global minimums of the standard benchmark functions are almost obtained.
Prediction of the blast-induced is an important issue in Shur river dam, Iran. The nonlinear math... more Prediction of the blast-induced is an important issue in Shur river dam, Iran. The nonlinear mathematical models can provide an appropriate flexibility to achieve the accurate predictions of the blast-induced airblast. In this paper, a set of nonlinear mathematical models with eight empirical relations, which are added based on the logarithmic and power basic functions, are selected to calibrate of the mine blasting airblast using two input variables, i.e. maximum charge per delay (MC) and distance from the blast-point (DI). A general regression analysis is proposed to calibrate the nonlinear models using a modified conjugate Fletcher and Reeves (FR) method using a limited scalar factor and dynamic step size to achieve the stabilization in nonlinear modeling. Finally, three simple empirical models are chosen to implement the prediction of the blast-induced airblast. The proposed empirical models were compared with the United States Bureau of Mines (USBM) model using several error statistics. The results indicate that the proposed modified FR model provides an appropriate calibration for the nonlinear regression analysis. Also, it was found that the empirical model proposed in this study, with the root mean square error (RMSE) of 3.79, is more accurate than USBM, with the RMSE of 4.22, and can be applied to other sites for predicting the airblast.
مجله علوم روانشناختی, May 1, 2022
Background: Social Anxiety Disorder is considered as the most common disorder among the anxiety d... more Background: Social Anxiety Disorder is considered as the most common disorder among the anxiety disorders that causes various psychological problems. Therefore, it is important to investigate the effective therapeutic interventions in order to reduce these problems. Aims: The present study evaluated the efficacy of intensive short-term dynamic psychotherapy (ISTDP) on self-esteem, emotion regulation, and defense mechanisms in people suffering from social anxiety disorder. Methods: A quasi-experimental desins of pre-test, post-test, and follow-up was used in this study. The statistical population included all men with social anxiety disorder in Shiraz who had refered to the centers of counseling, and psychological services in 1399. For this purpose20 of them were purposefully selected, and randomly assigned to the experimental, and control groups. Participants completed the self-esteem questionnaire of Cooper-Smith (1967), defense styles of Andrews et al. (1993), and emotion regulation questionnaire of Gratz (2004) before treatment. Then the experimental group received treatment sessions in 2 sessions of 60 minutes per week in 15 sessions. At the end of treatment sessions, and 2 months later, all the participants in 2 groups of experiment, and control completed the study questionairs again. Results: The results showed that ISTDP can increase self-esteem of people with social anxiety disorder (p<0.01). This therapy can affect defense mechanisms of people suffering from social anxiety disorder in the way that mature defense mechanisms increase, and immature defense mechanisms decrease in these people(p<0.01). The findings also showed that ISTDP decreases emotion dysregulation in people with social anxiety disorder (p<0.01). Conclusion: It can be said that psychotherapists can use ISTDP to improve common emotional problems, self-esteem, and ineffctive defenses in people with social anxiety disorder.
Disclaimer The AM is yet to be copyedited and formatted in journal house style but can still be r... more Disclaimer The AM is yet to be copyedited and formatted in journal house style but can still be read and referenced by quoting its unique reference number, the digital object identifier (DOI). Once the AM has been typeset, an 'uncorrected proof' PDF will replace the 'accepted manuscript' PDF. These formatted articles may still be corrected by the authors. During the Production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also. Version of record The final edited article will be published in PDF and HTML and will contain all author corrections and is considered the version of record. Authors wishing to reference an article published Ahead of Print should quote its DOI. When an issue becomes available, queuing Ahead of Print articles will move to that issue's Table of Contents. When the article is published in a journal issue, the full reference should be cited in addition to the DOI.
Reusing recycled materials made from concrete wastes is one way of preserving natural resources a... more Reusing recycled materials made from concrete wastes is one way of preserving natural resources and promoting sustainable development. The effect of pozzolan additives (silica fume (SF) and nanosilica (NS)) on the strength, durability and microstructural properties of concrete made with 100% recycled aggregates (RAs) was investigated in this study. The concrete mixtures were made with complete substitution of natural aggregates with the same grading of RAs. As proportions of the cementitious materials, the contents of SF were 0%, 5%, 10%, 15% and 20% and the contents of NS were 0%, 1%, 2%, 3% and 4%. Compressive strength, tensile strength, flexural strength, water permeability and chloride permeability were measured at 7, 28 and 90 days. Microstructural investigations were performed using scanning electron microscopy on selected concrete mixtures. The test results showed that the addition of the pozzolan additives improved microstructure and strength and durability properties of the...
Nowadays, optimization meta-heuristic algorithms are used in different fields of science, includi... more Nowadays, optimization meta-heuristic algorithms are used in different fields of science, including a computer, mechanics and civil engineering. The algorithms are inspired by the laws governing nature, such as the principle of physics, an association of animals or finding and hunting food by animals. Using the smell sense of a bee insect, called Smell Bees Optimization (SBO), the present paper proposes an optimization algorithm that is meta-heuristic and inspired by nature. To verify and validate, the proposed algorithm, benchmark functions and engineering design examples were applied, which were previously optimized using different algorithms. In doing so, such as a cantilever beam, pressure vessel, three-bar truss, tension/ compression spring and a welded beam were applied, which were previously optimized using different algorithms. In order to run programming, MATLAB was used. The results obtained by SBO are compared to the previous algorithms, optimized solutions of engineering examples are improved, and the target global minimums of the standard benchmark functions are almost obtained.
This paper presents intelligent models for solving problems related to retaining walls in geotech... more This paper presents intelligent models for solving problems related to retaining walls in geotechnics. To do this, safety factors of 2800 retaining walls were modeled and recorded considering different effective parameters of retaining walls (RWs), i.e., height of the wall, wall thickness, friction angle, density of the soil, and density of the rock. Two intelligent methodologies including a pre-developed artificial neural network (ANN) and a combination of artificial bee colony (ABC) and ANN were selectively developed to approximate safety factors of RWs. In the new network, ABC was used to optimize weight and biases of ANN to receive higher level of accuracy and performance prediction. Many ANN and ABC-ANN models were built considering the most influential parameters of them and their performances were evaluated using coefficient of determination (R 2) and root mean square error (RMSE) performance indices. After developing the mentioned models, it was found that the new hybrid model is able to increase network performance capacity significantly. For instance, R 2 values of 0.982 and 0.985 for training and testing of ABC-ANN model, respectively, compared to these values of 0.920 and 0.924 for ANN model showed that the new hybrid model can be introduced as a capable enough technique in the field of this study for estimating safety factors of RWs.
Social support is a complex and multifaceted construct. Thus, It is important that a given social... more Social support is a complex and multifaceted construct. Thus, It is important that a given social support scale be theoretically grounded and its purview clearly defined. The purpose of this study was to examine the reliability, validity and factor structure of the Iranian version of the Multidimensional Scale of Perceived Social Support (MSPSS). The sample study included 176 consecutive myocardial infarction (MI) patients admitted to the coronary care unit (CCU) ward of nine hospitals in Isfahan, Iran, and 71 consecutive subjects from the general population. They all filled out the final Iranian version of the MSPSS and also 71 participants filled out the MSPSS twice over a 2-month period. Factor analysis, Cronbach's α coefficient and Pearson's correlation coefficient correlation were used to analyze data. Factor analysis of the scores of the patient and healthy samples yielded a three-factor structure, including family, friends and significant others. The percentage of var...
Prediction of the blast-induced is an important issue in Shur river dam, Iran. The nonlinear math... more Prediction of the blast-induced is an important issue in Shur river dam, Iran. The nonlinear mathematical models can provide an appropriate flexibility to achieve the accurate predictions of the blast-induced airblast. In this paper, a set of nonlinear mathematical models with eight empirical relations, which are added based on the logarithmic and power basic functions, are selected to calibrate of the mine blasting airblast using two input variables, i.e. maximum charge per delay (MC) and distance from the blast-point (DI). A general regression analysis is proposed to calibrate the nonlinear models using a modified conjugate Fletcher and Reeves (FR) method using a limited scalar factor and dynamic step size to achieve the stabilization in nonlinear modeling. Finally, three simple empirical models are chosen to implement the prediction of the blast-induced airblast. The proposed empirical models were compared with the United States Bureau of Mines (USBM) model using several error statistics. The results indicate that the proposed modified FR model provides an appropriate calibration for the nonlinear regression analysis. Also, it was found that the empirical model proposed in this study, with the root mean square error (RMSE) of 3.79, is more accurate than USBM, with the RMSE of 4.22, and can be applied to other sites for predicting the airblast.
Connections are considered to be one of the most prominent components of steel moment frames and ... more Connections are considered to be one of the most prominent components of steel moment frames and have received studious attention in recent years. The core problem of welded connections is premature brittle fracture of weld in the critical beam-to-column connection region. Within the framework of this issue, various approaches have been proposed to solve the mentioned problem. Intentional weakening of the beam web or flange is in line with the purpose of leading the plastic hinge away from the column face, hence, increasing the ductility. The aim of this research is to investigate the behavior of interior connections subjected to monotonic lateral loading in case of presence of openings in beam web or flange. To do so, an ordinary fully welded rigid connection, reduced beam section, reduced web section, and drilled flange connection models are simulated numerically, utilizing finite element software, ANSYS. The results indicate that scrupulous selection of opening sizes are of great...
Journal of Seismology and Earthquake Engineering, 2010
The effectiveness of FRP jackets for increasing the compression strength, shear strength and duct... more The effectiveness of FRP jackets for increasing the compression strength, shear strength and ductility of reinforced concrete (RC) columns was demonstrated in many studies, but the influence of FRP jacketing on the flexural capacity of columns is minimal. In this paper, a new retrofit method, which utilized near surface mounted (NSM) fiber reinforced polymer (FRP), was studied aiming to improve the flexural capacity of RC columns subjected to bending and compression. This technique is based on bonding fiber reinforced polymer (FRP) bars into grooves cut in the cover of RC columns. For this purpose, five reinforced concrete column specimens were designed, constructed and subjected to constant axial compression and lateral cyclic loading. In addition, the strengthened columns were wrapped with carbon composites to satisfy seismic detailing requirements. The test results show that by using the NSM technique, the flexural strength and lateral load capacity of the columns increase signif...
The optimal design of real-scale structures under frequency constraints is a crucial problem for ... more The optimal design of real-scale structures under frequency constraints is a crucial problem for engineers. In this paper, linear analysis, as well as optimization by considering natural frequency constraints, have been used for real-scale symmetric structures. These structures require a lot of time to minimize weight and displacement. The cyclically symmetric properties have been used for decreasing time. The structure has been decomposed into smaller repeated portions termed substructures. Only the substructure elements are needed when analyzing and designing with the concept of cyclic symmetries. The frequency constrained design of real-scale structures is a complex optimization problem that has many local optimal answers. In this research, the Gold Rush Optimization (GRO) algorithm has been used to optimize weight and displacement performances due to its effectiveness and robustness against uncertainties. The efficacy of the concept of cyclic symmetry to minimize the time calcul...
This paper shows the results of an experimental study on the behavior of rectangular reinforced c... more This paper shows the results of an experimental study on the behavior of rectangular reinforced concrete columns that strengthened in bending with NSM FRP bars and CFRP jacketing under combined compression axial load and cyclic lateral loading. Near surface mounted (NSM) fiber reinforced polymer (FRP) is one of the best retrofitting techniques for reinforced concrete (RC) structures. This technique is based on inserting fiber reinforced polymer bars into slits in the cover of reinforced concrete members. For this purpose, seven rectangular RC columns including one control specimen constructed and tested under constant axial load and lateral cyclic displacement. Experimental parameters include different ratios of NSM FRP bar, maximum lateral load capacity, and failure modes are describes based on the test results. The crack patterns in the specimens are also presented. Also, the study was designed to evaluate the necessity of anchoring the end of NSM FRP bars in the foundation. The t...
International Journal of Concrete Structures and Materials, 2019
This research describes the results of an experimental work that aimed to investigate the flexura... more This research describes the results of an experimental work that aimed to investigate the flexural capacity of RC columns with low longitudinal reinforcement ratio that was strengthened with near surface mounted GFRP bars. The experimental program consisted of four square reinforced concrete columns, including one control specimen that were designed with a longitudinal reinforcement ratio below the minimum required ratio of 1% specified by RC design codes. Three of the four specimens were strengthened with different ratios NSM GFRP bar. The specimens were tested under a combined axial compressive load and lateral cyclic displacement to evaluate this retrofit method for the flexural improvement of RC columns. The efficacy of the proposed strengthening method on the flexural capacity, failure modes, hysteretic curves, energy dissipation capacity, and stiffness are discussed on the basis of the test results. The experimental results demonstrated that the contribution of GFRP bars to the flexural capacity of RC columns was significant. Also, an analytical procedure for calculating the bending moment capacity of RC columns strengthened with GFRP bars subjected to axial and lateral is proposed. The model accuracy is demonstrated by comparing the model predictions with the experimental results. The flexural capacity calculated by this method were in good agreement with the experimental results.
Advances in FRP Composites in Civil Engineering, 2011
Near surface mounted (NSM) fiber-reinforced polymer (FRP) reinforcement is one of the latest and ... more Near surface mounted (NSM) fiber-reinforced polymer (FRP) reinforcement is one of the latest and most promising strengthening techniques for reinforced concrete (RC) structures. This technique based on bonding carbon or glass fiber reinforced polymer (CFRP or GFRP) bars (rods or laminate strips) into pre-cut grooves on the concrete cover of the elements to strength. In this work, a strengthening technique based on near surface mounted (NSM) carbon fiber rods is used to improve the flexural capacity of columns subjected to bending and compression. We describe the strengthening technique and report the experimental results in the strengthening process. The results obtained in series of reinforced concrete columns, subjected to combined constant axial compression and lateral cyclic loading, show that a significant increase on the load carrying capacity and flexural resistance can be achieved by using the NSM technique.
The effectiveness of fibre reinforced polymer (FRP) jackets for increasing the compression streng... more The effectiveness of fibre reinforced polymer (FRP) jackets for increasing the compression strength, shear strength and ductility of reinforced concrete (RC) columns has been demonstrated in many studies, but the influence of fibre reinforced polymer jacketing on the flexural capacity of columns is minimal. In this paper, a new retrofit method, which utilises near-surface mounted (NSM), fibre reinforced polymer, is developed to improve the flexural capacity of reinforced concrete columns subjected to bending and compression. This technique is based on bonding fibre reinforced polymer bars into grooves cut in the cover of reinforced concrete columns. For this purpose, seven reinforced concrete column specimens were designed, constructed and subjected to constant axial compression and lateral cyclic loading. In addition, the strengthened columns were wrapped with carbon composites to satisfy seismic detailing requirements. The test results show that the proposed strengthening techniqu...
Nowadays, optimization meta-heuristic algorithms are used in different fields of science, includi... more Nowadays, optimization meta-heuristic algorithms are used in different fields of science, including a computer, mechanics and civil engineering. The algorithms are inspired by the laws governing nature, such as the principle of physics, an association of animals or finding and hunting food by animals. Using the smell sense of a bee insect, called Smell Bees Optimization (SBO), the present paper proposes an optimization algorithm that is meta-heuristic and inspired by nature. To verify and validate, the proposed algorithm, benchmark functions and engineering design examples were applied, which were previously optimized using different algorithms. In doing so, such as a cantilever beam, pressure vessel, three-bar truss, tension/ compression spring and a welded beam were applied, which were previously optimized using different algorithms. In order to run programming, MATLAB was used. The results obtained by SBO are compared to the previous algorithms, optimized solutions of engineering examples are improved, and the target global minimums of the standard benchmark functions are almost obtained.
Prediction of the blast-induced is an important issue in Shur river dam, Iran. The nonlinear math... more Prediction of the blast-induced is an important issue in Shur river dam, Iran. The nonlinear mathematical models can provide an appropriate flexibility to achieve the accurate predictions of the blast-induced airblast. In this paper, a set of nonlinear mathematical models with eight empirical relations, which are added based on the logarithmic and power basic functions, are selected to calibrate of the mine blasting airblast using two input variables, i.e. maximum charge per delay (MC) and distance from the blast-point (DI). A general regression analysis is proposed to calibrate the nonlinear models using a modified conjugate Fletcher and Reeves (FR) method using a limited scalar factor and dynamic step size to achieve the stabilization in nonlinear modeling. Finally, three simple empirical models are chosen to implement the prediction of the blast-induced airblast. The proposed empirical models were compared with the United States Bureau of Mines (USBM) model using several error statistics. The results indicate that the proposed modified FR model provides an appropriate calibration for the nonlinear regression analysis. Also, it was found that the empirical model proposed in this study, with the root mean square error (RMSE) of 3.79, is more accurate than USBM, with the RMSE of 4.22, and can be applied to other sites for predicting the airblast.
مجله علوم روانشناختی, May 1, 2022
Background: Social Anxiety Disorder is considered as the most common disorder among the anxiety d... more Background: Social Anxiety Disorder is considered as the most common disorder among the anxiety disorders that causes various psychological problems. Therefore, it is important to investigate the effective therapeutic interventions in order to reduce these problems. Aims: The present study evaluated the efficacy of intensive short-term dynamic psychotherapy (ISTDP) on self-esteem, emotion regulation, and defense mechanisms in people suffering from social anxiety disorder. Methods: A quasi-experimental desins of pre-test, post-test, and follow-up was used in this study. The statistical population included all men with social anxiety disorder in Shiraz who had refered to the centers of counseling, and psychological services in 1399. For this purpose20 of them were purposefully selected, and randomly assigned to the experimental, and control groups. Participants completed the self-esteem questionnaire of Cooper-Smith (1967), defense styles of Andrews et al. (1993), and emotion regulation questionnaire of Gratz (2004) before treatment. Then the experimental group received treatment sessions in 2 sessions of 60 minutes per week in 15 sessions. At the end of treatment sessions, and 2 months later, all the participants in 2 groups of experiment, and control completed the study questionairs again. Results: The results showed that ISTDP can increase self-esteem of people with social anxiety disorder (p<0.01). This therapy can affect defense mechanisms of people suffering from social anxiety disorder in the way that mature defense mechanisms increase, and immature defense mechanisms decrease in these people(p<0.01). The findings also showed that ISTDP decreases emotion dysregulation in people with social anxiety disorder (p<0.01). Conclusion: It can be said that psychotherapists can use ISTDP to improve common emotional problems, self-esteem, and ineffctive defenses in people with social anxiety disorder.
Disclaimer The AM is yet to be copyedited and formatted in journal house style but can still be r... more Disclaimer The AM is yet to be copyedited and formatted in journal house style but can still be read and referenced by quoting its unique reference number, the digital object identifier (DOI). Once the AM has been typeset, an 'uncorrected proof' PDF will replace the 'accepted manuscript' PDF. These formatted articles may still be corrected by the authors. During the Production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also. Version of record The final edited article will be published in PDF and HTML and will contain all author corrections and is considered the version of record. Authors wishing to reference an article published Ahead of Print should quote its DOI. When an issue becomes available, queuing Ahead of Print articles will move to that issue's Table of Contents. When the article is published in a journal issue, the full reference should be cited in addition to the DOI.
Reusing recycled materials made from concrete wastes is one way of preserving natural resources a... more Reusing recycled materials made from concrete wastes is one way of preserving natural resources and promoting sustainable development. The effect of pozzolan additives (silica fume (SF) and nanosilica (NS)) on the strength, durability and microstructural properties of concrete made with 100% recycled aggregates (RAs) was investigated in this study. The concrete mixtures were made with complete substitution of natural aggregates with the same grading of RAs. As proportions of the cementitious materials, the contents of SF were 0%, 5%, 10%, 15% and 20% and the contents of NS were 0%, 1%, 2%, 3% and 4%. Compressive strength, tensile strength, flexural strength, water permeability and chloride permeability were measured at 7, 28 and 90 days. Microstructural investigations were performed using scanning electron microscopy on selected concrete mixtures. The test results showed that the addition of the pozzolan additives improved microstructure and strength and durability properties of the...
Nowadays, optimization meta-heuristic algorithms are used in different fields of science, includi... more Nowadays, optimization meta-heuristic algorithms are used in different fields of science, including a computer, mechanics and civil engineering. The algorithms are inspired by the laws governing nature, such as the principle of physics, an association of animals or finding and hunting food by animals. Using the smell sense of a bee insect, called Smell Bees Optimization (SBO), the present paper proposes an optimization algorithm that is meta-heuristic and inspired by nature. To verify and validate, the proposed algorithm, benchmark functions and engineering design examples were applied, which were previously optimized using different algorithms. In doing so, such as a cantilever beam, pressure vessel, three-bar truss, tension/ compression spring and a welded beam were applied, which were previously optimized using different algorithms. In order to run programming, MATLAB was used. The results obtained by SBO are compared to the previous algorithms, optimized solutions of engineering examples are improved, and the target global minimums of the standard benchmark functions are almost obtained.
This paper presents intelligent models for solving problems related to retaining walls in geotech... more This paper presents intelligent models for solving problems related to retaining walls in geotechnics. To do this, safety factors of 2800 retaining walls were modeled and recorded considering different effective parameters of retaining walls (RWs), i.e., height of the wall, wall thickness, friction angle, density of the soil, and density of the rock. Two intelligent methodologies including a pre-developed artificial neural network (ANN) and a combination of artificial bee colony (ABC) and ANN were selectively developed to approximate safety factors of RWs. In the new network, ABC was used to optimize weight and biases of ANN to receive higher level of accuracy and performance prediction. Many ANN and ABC-ANN models were built considering the most influential parameters of them and their performances were evaluated using coefficient of determination (R 2) and root mean square error (RMSE) performance indices. After developing the mentioned models, it was found that the new hybrid model is able to increase network performance capacity significantly. For instance, R 2 values of 0.982 and 0.985 for training and testing of ABC-ANN model, respectively, compared to these values of 0.920 and 0.924 for ANN model showed that the new hybrid model can be introduced as a capable enough technique in the field of this study for estimating safety factors of RWs.
Social support is a complex and multifaceted construct. Thus, It is important that a given social... more Social support is a complex and multifaceted construct. Thus, It is important that a given social support scale be theoretically grounded and its purview clearly defined. The purpose of this study was to examine the reliability, validity and factor structure of the Iranian version of the Multidimensional Scale of Perceived Social Support (MSPSS). The sample study included 176 consecutive myocardial infarction (MI) patients admitted to the coronary care unit (CCU) ward of nine hospitals in Isfahan, Iran, and 71 consecutive subjects from the general population. They all filled out the final Iranian version of the MSPSS and also 71 participants filled out the MSPSS twice over a 2-month period. Factor analysis, Cronbach's α coefficient and Pearson's correlation coefficient correlation were used to analyze data. Factor analysis of the scores of the patient and healthy samples yielded a three-factor structure, including family, friends and significant others. The percentage of var...
Prediction of the blast-induced is an important issue in Shur river dam, Iran. The nonlinear math... more Prediction of the blast-induced is an important issue in Shur river dam, Iran. The nonlinear mathematical models can provide an appropriate flexibility to achieve the accurate predictions of the blast-induced airblast. In this paper, a set of nonlinear mathematical models with eight empirical relations, which are added based on the logarithmic and power basic functions, are selected to calibrate of the mine blasting airblast using two input variables, i.e. maximum charge per delay (MC) and distance from the blast-point (DI). A general regression analysis is proposed to calibrate the nonlinear models using a modified conjugate Fletcher and Reeves (FR) method using a limited scalar factor and dynamic step size to achieve the stabilization in nonlinear modeling. Finally, three simple empirical models are chosen to implement the prediction of the blast-induced airblast. The proposed empirical models were compared with the United States Bureau of Mines (USBM) model using several error statistics. The results indicate that the proposed modified FR model provides an appropriate calibration for the nonlinear regression analysis. Also, it was found that the empirical model proposed in this study, with the root mean square error (RMSE) of 3.79, is more accurate than USBM, with the RMSE of 4.22, and can be applied to other sites for predicting the airblast.
Connections are considered to be one of the most prominent components of steel moment frames and ... more Connections are considered to be one of the most prominent components of steel moment frames and have received studious attention in recent years. The core problem of welded connections is premature brittle fracture of weld in the critical beam-to-column connection region. Within the framework of this issue, various approaches have been proposed to solve the mentioned problem. Intentional weakening of the beam web or flange is in line with the purpose of leading the plastic hinge away from the column face, hence, increasing the ductility. The aim of this research is to investigate the behavior of interior connections subjected to monotonic lateral loading in case of presence of openings in beam web or flange. To do so, an ordinary fully welded rigid connection, reduced beam section, reduced web section, and drilled flange connection models are simulated numerically, utilizing finite element software, ANSYS. The results indicate that scrupulous selection of opening sizes are of great...
Journal of Seismology and Earthquake Engineering, 2010
The effectiveness of FRP jackets for increasing the compression strength, shear strength and duct... more The effectiveness of FRP jackets for increasing the compression strength, shear strength and ductility of reinforced concrete (RC) columns was demonstrated in many studies, but the influence of FRP jacketing on the flexural capacity of columns is minimal. In this paper, a new retrofit method, which utilized near surface mounted (NSM) fiber reinforced polymer (FRP), was studied aiming to improve the flexural capacity of RC columns subjected to bending and compression. This technique is based on bonding fiber reinforced polymer (FRP) bars into grooves cut in the cover of RC columns. For this purpose, five reinforced concrete column specimens were designed, constructed and subjected to constant axial compression and lateral cyclic loading. In addition, the strengthened columns were wrapped with carbon composites to satisfy seismic detailing requirements. The test results show that by using the NSM technique, the flexural strength and lateral load capacity of the columns increase signif...
The optimal design of real-scale structures under frequency constraints is a crucial problem for ... more The optimal design of real-scale structures under frequency constraints is a crucial problem for engineers. In this paper, linear analysis, as well as optimization by considering natural frequency constraints, have been used for real-scale symmetric structures. These structures require a lot of time to minimize weight and displacement. The cyclically symmetric properties have been used for decreasing time. The structure has been decomposed into smaller repeated portions termed substructures. Only the substructure elements are needed when analyzing and designing with the concept of cyclic symmetries. The frequency constrained design of real-scale structures is a complex optimization problem that has many local optimal answers. In this research, the Gold Rush Optimization (GRO) algorithm has been used to optimize weight and displacement performances due to its effectiveness and robustness against uncertainties. The efficacy of the concept of cyclic symmetry to minimize the time calcul...
This paper shows the results of an experimental study on the behavior of rectangular reinforced c... more This paper shows the results of an experimental study on the behavior of rectangular reinforced concrete columns that strengthened in bending with NSM FRP bars and CFRP jacketing under combined compression axial load and cyclic lateral loading. Near surface mounted (NSM) fiber reinforced polymer (FRP) is one of the best retrofitting techniques for reinforced concrete (RC) structures. This technique is based on inserting fiber reinforced polymer bars into slits in the cover of reinforced concrete members. For this purpose, seven rectangular RC columns including one control specimen constructed and tested under constant axial load and lateral cyclic displacement. Experimental parameters include different ratios of NSM FRP bar, maximum lateral load capacity, and failure modes are describes based on the test results. The crack patterns in the specimens are also presented. Also, the study was designed to evaluate the necessity of anchoring the end of NSM FRP bars in the foundation. The t...
International Journal of Concrete Structures and Materials, 2019
This research describes the results of an experimental work that aimed to investigate the flexura... more This research describes the results of an experimental work that aimed to investigate the flexural capacity of RC columns with low longitudinal reinforcement ratio that was strengthened with near surface mounted GFRP bars. The experimental program consisted of four square reinforced concrete columns, including one control specimen that were designed with a longitudinal reinforcement ratio below the minimum required ratio of 1% specified by RC design codes. Three of the four specimens were strengthened with different ratios NSM GFRP bar. The specimens were tested under a combined axial compressive load and lateral cyclic displacement to evaluate this retrofit method for the flexural improvement of RC columns. The efficacy of the proposed strengthening method on the flexural capacity, failure modes, hysteretic curves, energy dissipation capacity, and stiffness are discussed on the basis of the test results. The experimental results demonstrated that the contribution of GFRP bars to the flexural capacity of RC columns was significant. Also, an analytical procedure for calculating the bending moment capacity of RC columns strengthened with GFRP bars subjected to axial and lateral is proposed. The model accuracy is demonstrated by comparing the model predictions with the experimental results. The flexural capacity calculated by this method were in good agreement with the experimental results.
Advances in FRP Composites in Civil Engineering, 2011
Near surface mounted (NSM) fiber-reinforced polymer (FRP) reinforcement is one of the latest and ... more Near surface mounted (NSM) fiber-reinforced polymer (FRP) reinforcement is one of the latest and most promising strengthening techniques for reinforced concrete (RC) structures. This technique based on bonding carbon or glass fiber reinforced polymer (CFRP or GFRP) bars (rods or laminate strips) into pre-cut grooves on the concrete cover of the elements to strength. In this work, a strengthening technique based on near surface mounted (NSM) carbon fiber rods is used to improve the flexural capacity of columns subjected to bending and compression. We describe the strengthening technique and report the experimental results in the strengthening process. The results obtained in series of reinforced concrete columns, subjected to combined constant axial compression and lateral cyclic loading, show that a significant increase on the load carrying capacity and flexural resistance can be achieved by using the NSM technique.
The effectiveness of fibre reinforced polymer (FRP) jackets for increasing the compression streng... more The effectiveness of fibre reinforced polymer (FRP) jackets for increasing the compression strength, shear strength and ductility of reinforced concrete (RC) columns has been demonstrated in many studies, but the influence of fibre reinforced polymer jacketing on the flexural capacity of columns is minimal. In this paper, a new retrofit method, which utilises near-surface mounted (NSM), fibre reinforced polymer, is developed to improve the flexural capacity of reinforced concrete columns subjected to bending and compression. This technique is based on bonding fibre reinforced polymer bars into grooves cut in the cover of reinforced concrete columns. For this purpose, seven reinforced concrete column specimens were designed, constructed and subjected to constant axial compression and lateral cyclic loading. In addition, the strengthened columns were wrapped with carbon composites to satisfy seismic detailing requirements. The test results show that the proposed strengthening techniqu...
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