Ihssan Tarsha - Academia.edu (original) (raw)

Papers by Ihssan Tarsha

International journal of masonry research and innovation, Dec 31, 2023

Jordan Journal of Civil Engineering, 2024

Improvements of reinforced concrete beams against the impact of torsional forces are among the mo... more Improvements of reinforced concrete beams against the impact of torsional forces are among the most researched issues in construction studies. In this paper, repairing and strengthening reinforced concrete beams using ferrocement laminates attached onto the surface of the beams and exposed to torsion were reviewed. This study aims to reveal the efficacy of the wrapping sides of ferrocement laminates. Previous experimental studies were conducted by using SBR as a slurry for strengthening beams by ferrocement from two-and three-side wrapping. Alternatively, the influence of using SBR as an ingredient of the mortar on the performance of the strengthened beams under torsion was discussed. The results showed that ferrocement is a practical alternative strengthening component for rehabilitating and repairing reinforced concrete beams. It was demonstrated that three-side wrapping improves the torsional behaviour in comparison with two-side wrapping. Also, the SBR preserved the required joining until failure for all the strengthened beams.

1st international conference on civil and earthquake engineering (ICCEE 2023) in Annaba, Algeria , 2023

This study investigates the performance of reinforced concrete (RC) columns following fire exposu... more This study investigates the performance of reinforced concrete (RC) columns following fire exposure. In the first phase of the study, we examined the effect of various high-temperature environments on the residual load-bearing capacity of columns. In the second phase, the strengthening method is intended to increase the concrete strength through confinement to restore or improve the load capacity of fire-damaged columns. The RC columns were damaged after being exposed to fire for different periods of time to the medium and long fire (30 or 90 min) of the ASTM-E119 from the four-sided standard fire curve and then tested under axial loading up to failure. Concrete's compressive strengths are 25, 30, 35, and 40 MPa. The results indicated that the column's bearing capacity decreases proportionally with the length of time it is subjected to fire. In addition, it was discovered that the fortifying procedure employed herein restored up to 180 percent of the capacity of columns exposed to fire for an hour. In terms of strength, the technique involving composite confinement and steel slabs produced superior results.

1st international conference on civil and earthquake engineering (ICCEE 2023) in Annaba, Algeria , 2023

This research presents a numerical study of the behavior of reinforced columns with a square cros... more This research presents a numerical study of the behavior of reinforced columns with a square cross section subjected to eccentric stress under the influence of fire. As a first step, the study examined the effects of exposing columns to fire with an increasing temperature up to 600°C for 60 minutes under eccentric loading conditions (e/b = 0, 0.1, 0.15, 0.20). As a second step, the columns were strengthened with a 100-mm concrete jacket and shirts supported by a steel structure consisting of vertical angles and horizontal spreaders to determine the effectiveness of the strengthening in increasing the resistance of these damaged columns. After the fire, this type of reinforcement is considered better than reinforcement with concrete shirts, reinforcement with carbon fiber-reinforced polymers, and others because of its advantages. There are many advantages to the ease and speed of implementation. The results showed that the columns that were repaired and strengthened after the fire with the steel structure casing led to a significant increase in resistance. It was found that the greater the thickness of the steel structure, the greater the resistance, and that the greater the eccentricity ratio, the lower the resistance as well as the collapse load.

International Conference on Construction Engineering Towards more Sustainable Structures 2022, 2022

Concrete structures are among the most common types of structural in the World, so studying the b... more Concrete structures are among the most common types of structural in the World, so studying the behavior and collapse of these structures is one of the most important fields of study. Failures occur in concrete structures because of many factors such as earthquakes, explosions, landslides, fire, and other causes. Fires still represent a prime threat to the safety of

 ABSTRACT  The effect of torsion moments on reinforced concrete beams have much attention and c... more  ABSTRACT  The effect of torsion moments on reinforced concrete beams have much attention and complicate ,that if these moments are combined with shear and bending moments or act alone (pure torsion). creating opening in these beams will reduce their strong a lot. This research study the effect of strengthening these beams , if we create opening in them , with CFRP to improve the ultimate torsion. The research conclude that creating an opening in the beams reduce the strength about 70% , while strengthen with CFRP increase the strength about three times compared with beams with opening.

In this research, a strengthening method is suggest to confine reinforced concrete circular colum... more In this research, a strengthening method is suggest to confine reinforced concrete circular columns, exposed to axial force, by using a steel structure, which consists of vertical plates extending all over the height of the column and transverse plates (ring plates). The research represents an experimental study to show the effect of this strengthening form on the behavior of reinforced concrete circular columns by using different compressive strengths of concrete, and its effect on reinforced concrete circular columns(ultimate load, ductility, and models of failure). The research makes it clear that confining of reinforced concrete circular columns by steel structure results in an increase in the ultimate axial load and ductility. Models of failure change with a strengthening form. The confinement has a clear effect on the low compressive strength of concrete.

Compressive strength of concrete is the criterion that determines the validity of using concrete ... more Compressive strength of concrete is the criterion that determines the validity of using concrete mix in engineering projects. Compressive strength of concrete depends on a lot of factors which don't have clear relationship , in addition that some of them are unclear and couldn't be measured. Therefore, finding method to estimate compressive strength of concrete specimen before the placement with acceptable accuracy is desirable, even if there is lack of some information like manner of placement or boundary conditions. This study presents first step to benefit of artificial neural network techniques which prove it's effective in a lot of applications in medical , engineering , financial. . .etc. We choose feed forward networks using back-propagation depending on weights and kinds of materials in the mix, and training the network with data of real experiments, and then test it. The results demonstrates that neural networks are effective in estimating the compressive strength of concrete based on the mix properties , and in learning even there is lack of some influenced factors.

This paper presents results from an experimental study including testing five reinforced concrete... more This paper presents results from an experimental study including testing five reinforced concrete beams in order to investigate the efficiency of external strengthening of such beams when provided with large openings within their shear zones. Firstly tow beams were considered. One of these beams was solid without any openings and was considered as a control beam. The second beam was provided with one opening within the shear zone but without any strengthening and was also considered as a control beam. Secondly, three beams provided with openings at the same location and having the same dimensions like the second. Such three beams were externally strengthened with steel plates along the opening edges. It was found that the steel plates used for strengthening and its configuration scheme significantly affects the efficiency of strengthening in terms of beam deflection, steel strain, cracking, ultimate capacity and failure mode because using steel plates restored the beam shear strength .Finally, theoretical analysis was performed for all tested beams with openings in order to calculate the ultimate shear force carried by such beams. Equations presented by empirical formulas found in the literature were used to perform the theoretical analysis. Good agreement was observed between the theoretical results and the experimental ones.

The purpose of this research is studying the effect of openings on the behavior of reinforced con... more The purpose of this research is studying the effect of openings on the behavior of reinforced concrete beams under shear action using three dimensions nonlinear model by finite element method. The beams are simply supported with rectangular section and without additional reinforcement in opening region. The opening is rectangular in shape with variable dimensions and constant position from the support. Studying the effect of changing depth and length of the opening on the behavior of the reinforced concrete beams was conducted. Modeling of the beams was made using Ansys package which uses finite element technique .The ultimate load , the modes of cracks , (load-deflection) relationship and the mode of failure for every beam were achieved. The study showed that introducing an opening in shear region reduces the strength and alter the mode of failure from flexural failure to shear failure , and any addition in the depth or length of the opening lead to early cracks , more deflections and less ultimate failure load. Also the study showed a large approximate between the analytical and experimental results for solid beam without opening

The aim of this study is to numerically investigate the feasibility of confinement, the load carr... more The aim of this study is to numerically investigate the feasibility of confinement, the load carrying capacity and the temperature at which the confinement become obsolete for a RC column with dimensions of [200x200x 800 mm] subjected to a standard fire loads (ISO834) from four sides. The study was carried out using the research-oriented FE code ANSYS APDL. ANSYS can integrate the nonlinear behavior of concrete by accounting for both crushing under compression stresses and cracking under tensile stresses, and well as the bilinear behavior of the reinforcing steel.The Numerical program was subcategorized into two major groups. The first one consisted of thirteen models. Those models were analyzed under static loading conditions. The second group consisted of 72 models. The models in this group where subjected to both structural and thermal loading conditions. The structural loading was in a form of static service loads, while the thermal loading was in a form of standard fire curve that has been applied to the four faces of the column.The numerical results were compared with experimental results as far as possible, in order to verify the accuracy of the numerical models used. The numerical analysis aimed to study of the effect of many variables, i.e., the diameter of the lateral reinforcement, the diameter of the longitudinal reinforcement.The results revealed the accuracy of the analytical models when compared to the experimental studies. A positive effect was captured in terms of the load carrying capacity and delaying the failure time, i.e., loss in confinement effect, when increasing 1) the diameter of the longitudinal, 2) the diameter of the transverse reinforcement and Additionally, the results indicated an increase in the column loading time under thermal loading conditions when static design loads are applied. And when the percentage of failure load increased, the time of carrying columns of fire decreased. Keywords : Finite Element Theory, Thermal Analysis, Reinforced Concrete Columns

Solution of a problem of elasticity requires the solution of a system of 15 equations with 15 unk... more Solution of a problem of elasticity requires the solution of a system of 15 equations with 15 unknowns. A symmetric elimination of some the unknowns has allowed us to reduce the system of equations, either in terms of displacement or in terms of stresses. This suggests various methods that can be used in solving elasticity problems. Some of these methods depend primarily on intuition, while other are based on a systematic application of techniques of applied mathematics. This paper focuses on the numerical method for solution of two-dimensional elasticity problem.

FRP reinforced polymers are widely accepted for use in civil engineering applications to strength... more FRP reinforced polymers are widely accepted for use in civil engineering applications to strengthen constructions and application of confinement on the concrete columns, thereby increasing their ductility and increasing their carrying capacity as these materials are characterized by high tensile strength. With the development of computer simulation theories to study the behavior of elements and structures under the influence of different loads (static, dynamic, thermal, etc.), it is possible to study the behavior of concrete columns under the influence of axial vertical and non-axial structural loads, and compare the results with previous research, thus saving time, effort and cost instead Of laboratory testing. In this paper, an analytical study was conducted using the ANSYS Workbench method, which follows the finite element method, to determine the effect of confinement using CFRP on carrying capacity of concrete columns and to compare analytical results with experimental results.

International journal of masonry research and innovation, Dec 31, 2023

Jordan Journal of Civil Engineering, 2024

Improvements of reinforced concrete beams against the impact of torsional forces are among the mo... more Improvements of reinforced concrete beams against the impact of torsional forces are among the most researched issues in construction studies. In this paper, repairing and strengthening reinforced concrete beams using ferrocement laminates attached onto the surface of the beams and exposed to torsion were reviewed. This study aims to reveal the efficacy of the wrapping sides of ferrocement laminates. Previous experimental studies were conducted by using SBR as a slurry for strengthening beams by ferrocement from two-and three-side wrapping. Alternatively, the influence of using SBR as an ingredient of the mortar on the performance of the strengthened beams under torsion was discussed. The results showed that ferrocement is a practical alternative strengthening component for rehabilitating and repairing reinforced concrete beams. It was demonstrated that three-side wrapping improves the torsional behaviour in comparison with two-side wrapping. Also, the SBR preserved the required joining until failure for all the strengthened beams.

1st international conference on civil and earthquake engineering (ICCEE 2023) in Annaba, Algeria , 2023

This study investigates the performance of reinforced concrete (RC) columns following fire exposu... more This study investigates the performance of reinforced concrete (RC) columns following fire exposure. In the first phase of the study, we examined the effect of various high-temperature environments on the residual load-bearing capacity of columns. In the second phase, the strengthening method is intended to increase the concrete strength through confinement to restore or improve the load capacity of fire-damaged columns. The RC columns were damaged after being exposed to fire for different periods of time to the medium and long fire (30 or 90 min) of the ASTM-E119 from the four-sided standard fire curve and then tested under axial loading up to failure. Concrete's compressive strengths are 25, 30, 35, and 40 MPa. The results indicated that the column's bearing capacity decreases proportionally with the length of time it is subjected to fire. In addition, it was discovered that the fortifying procedure employed herein restored up to 180 percent of the capacity of columns exposed to fire for an hour. In terms of strength, the technique involving composite confinement and steel slabs produced superior results.

1st international conference on civil and earthquake engineering (ICCEE 2023) in Annaba, Algeria , 2023

This research presents a numerical study of the behavior of reinforced columns with a square cros... more This research presents a numerical study of the behavior of reinforced columns with a square cross section subjected to eccentric stress under the influence of fire. As a first step, the study examined the effects of exposing columns to fire with an increasing temperature up to 600°C for 60 minutes under eccentric loading conditions (e/b = 0, 0.1, 0.15, 0.20). As a second step, the columns were strengthened with a 100-mm concrete jacket and shirts supported by a steel structure consisting of vertical angles and horizontal spreaders to determine the effectiveness of the strengthening in increasing the resistance of these damaged columns. After the fire, this type of reinforcement is considered better than reinforcement with concrete shirts, reinforcement with carbon fiber-reinforced polymers, and others because of its advantages. There are many advantages to the ease and speed of implementation. The results showed that the columns that were repaired and strengthened after the fire with the steel structure casing led to a significant increase in resistance. It was found that the greater the thickness of the steel structure, the greater the resistance, and that the greater the eccentricity ratio, the lower the resistance as well as the collapse load.

International Conference on Construction Engineering Towards more Sustainable Structures 2022, 2022

Concrete structures are among the most common types of structural in the World, so studying the b... more Concrete structures are among the most common types of structural in the World, so studying the behavior and collapse of these structures is one of the most important fields of study. Failures occur in concrete structures because of many factors such as earthquakes, explosions, landslides, fire, and other causes. Fires still represent a prime threat to the safety of

 ABSTRACT  The effect of torsion moments on reinforced concrete beams have much attention and c... more  ABSTRACT  The effect of torsion moments on reinforced concrete beams have much attention and complicate ,that if these moments are combined with shear and bending moments or act alone (pure torsion). creating opening in these beams will reduce their strong a lot. This research study the effect of strengthening these beams , if we create opening in them , with CFRP to improve the ultimate torsion. The research conclude that creating an opening in the beams reduce the strength about 70% , while strengthen with CFRP increase the strength about three times compared with beams with opening.

In this research, a strengthening method is suggest to confine reinforced concrete circular colum... more In this research, a strengthening method is suggest to confine reinforced concrete circular columns, exposed to axial force, by using a steel structure, which consists of vertical plates extending all over the height of the column and transverse plates (ring plates). The research represents an experimental study to show the effect of this strengthening form on the behavior of reinforced concrete circular columns by using different compressive strengths of concrete, and its effect on reinforced concrete circular columns(ultimate load, ductility, and models of failure). The research makes it clear that confining of reinforced concrete circular columns by steel structure results in an increase in the ultimate axial load and ductility. Models of failure change with a strengthening form. The confinement has a clear effect on the low compressive strength of concrete.

Compressive strength of concrete is the criterion that determines the validity of using concrete ... more Compressive strength of concrete is the criterion that determines the validity of using concrete mix in engineering projects. Compressive strength of concrete depends on a lot of factors which don't have clear relationship , in addition that some of them are unclear and couldn't be measured. Therefore, finding method to estimate compressive strength of concrete specimen before the placement with acceptable accuracy is desirable, even if there is lack of some information like manner of placement or boundary conditions. This study presents first step to benefit of artificial neural network techniques which prove it's effective in a lot of applications in medical , engineering , financial. . .etc. We choose feed forward networks using back-propagation depending on weights and kinds of materials in the mix, and training the network with data of real experiments, and then test it. The results demonstrates that neural networks are effective in estimating the compressive strength of concrete based on the mix properties , and in learning even there is lack of some influenced factors.

This paper presents results from an experimental study including testing five reinforced concrete... more This paper presents results from an experimental study including testing five reinforced concrete beams in order to investigate the efficiency of external strengthening of such beams when provided with large openings within their shear zones. Firstly tow beams were considered. One of these beams was solid without any openings and was considered as a control beam. The second beam was provided with one opening within the shear zone but without any strengthening and was also considered as a control beam. Secondly, three beams provided with openings at the same location and having the same dimensions like the second. Such three beams were externally strengthened with steel plates along the opening edges. It was found that the steel plates used for strengthening and its configuration scheme significantly affects the efficiency of strengthening in terms of beam deflection, steel strain, cracking, ultimate capacity and failure mode because using steel plates restored the beam shear strength .Finally, theoretical analysis was performed for all tested beams with openings in order to calculate the ultimate shear force carried by such beams. Equations presented by empirical formulas found in the literature were used to perform the theoretical analysis. Good agreement was observed between the theoretical results and the experimental ones.

The purpose of this research is studying the effect of openings on the behavior of reinforced con... more The purpose of this research is studying the effect of openings on the behavior of reinforced concrete beams under shear action using three dimensions nonlinear model by finite element method. The beams are simply supported with rectangular section and without additional reinforcement in opening region. The opening is rectangular in shape with variable dimensions and constant position from the support. Studying the effect of changing depth and length of the opening on the behavior of the reinforced concrete beams was conducted. Modeling of the beams was made using Ansys package which uses finite element technique .The ultimate load , the modes of cracks , (load-deflection) relationship and the mode of failure for every beam were achieved. The study showed that introducing an opening in shear region reduces the strength and alter the mode of failure from flexural failure to shear failure , and any addition in the depth or length of the opening lead to early cracks , more deflections and less ultimate failure load. Also the study showed a large approximate between the analytical and experimental results for solid beam without opening

The aim of this study is to numerically investigate the feasibility of confinement, the load carr... more The aim of this study is to numerically investigate the feasibility of confinement, the load carrying capacity and the temperature at which the confinement become obsolete for a RC column with dimensions of [200x200x 800 mm] subjected to a standard fire loads (ISO834) from four sides. The study was carried out using the research-oriented FE code ANSYS APDL. ANSYS can integrate the nonlinear behavior of concrete by accounting for both crushing under compression stresses and cracking under tensile stresses, and well as the bilinear behavior of the reinforcing steel.The Numerical program was subcategorized into two major groups. The first one consisted of thirteen models. Those models were analyzed under static loading conditions. The second group consisted of 72 models. The models in this group where subjected to both structural and thermal loading conditions. The structural loading was in a form of static service loads, while the thermal loading was in a form of standard fire curve that has been applied to the four faces of the column.The numerical results were compared with experimental results as far as possible, in order to verify the accuracy of the numerical models used. The numerical analysis aimed to study of the effect of many variables, i.e., the diameter of the lateral reinforcement, the diameter of the longitudinal reinforcement.The results revealed the accuracy of the analytical models when compared to the experimental studies. A positive effect was captured in terms of the load carrying capacity and delaying the failure time, i.e., loss in confinement effect, when increasing 1) the diameter of the longitudinal, 2) the diameter of the transverse reinforcement and Additionally, the results indicated an increase in the column loading time under thermal loading conditions when static design loads are applied. And when the percentage of failure load increased, the time of carrying columns of fire decreased. Keywords : Finite Element Theory, Thermal Analysis, Reinforced Concrete Columns

Solution of a problem of elasticity requires the solution of a system of 15 equations with 15 unk... more Solution of a problem of elasticity requires the solution of a system of 15 equations with 15 unknowns. A symmetric elimination of some the unknowns has allowed us to reduce the system of equations, either in terms of displacement or in terms of stresses. This suggests various methods that can be used in solving elasticity problems. Some of these methods depend primarily on intuition, while other are based on a systematic application of techniques of applied mathematics. This paper focuses on the numerical method for solution of two-dimensional elasticity problem.

FRP reinforced polymers are widely accepted for use in civil engineering applications to strength... more FRP reinforced polymers are widely accepted for use in civil engineering applications to strengthen constructions and application of confinement on the concrete columns, thereby increasing their ductility and increasing their carrying capacity as these materials are characterized by high tensile strength. With the development of computer simulation theories to study the behavior of elements and structures under the influence of different loads (static, dynamic, thermal, etc.), it is possible to study the behavior of concrete columns under the influence of axial vertical and non-axial structural loads, and compare the results with previous research, thus saving time, effort and cost instead Of laboratory testing. In this paper, an analytical study was conducted using the ANSYS Workbench method, which follows the finite element method, to determine the effect of confinement using CFRP on carrying capacity of concrete columns and to compare analytical results with experimental results.