The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Brahim Benmokrane - One of the best experts on this subject based on the ideXlab platform.
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Punching Shear Behavior of Two-Way Slabs Reinforced with FRP Shear Reinforcement
Journal of Composites for Construction, 2015Co-Authors: Mohamed Hassan, Ehab A Ahmed, Brahim BenmokraneAbstract:AbstractThis study investigated the punching shear behavior of two-way concrete slabs with glass-fiber-reinforced polymer (GFRP) bars as Flexural Reinforcement and FRP stirrups (glass or carbon) as shear Reinforcement. A total of 10 full-scale interior slab-column specimens measuring 2,500×2,500 mm, with thicknesses of either 200 or 350 mm, and 300×300-mm square column stubs were fabricated and tested under monotonic concentric loading until failure. These tests aimed at investigating the behavior of GFRP-reinforced two-way concrete slabs reinforced with FRP stirrups as shear Reinforcement and evaluating their contribution to the punching shear capacity. The investigated parameters were the Flexural Reinforcement ratio and the shear Reinforcement type (glass FRP and carbon FRP stirrups) and ratio. The test results revealed that using FRP stirrups as shear Reinforcement increased the punching shear strength and deformation capacity of the test slabs. The increased punching shear strength and deformation c...
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Scaling of strength of FRP reinforced concrete beams without shear Reinforcement
2008Co-Authors: Fabio Matta, Antonio Nanni, T. M. Hernandez, Brahim BenmokraneAbstract:Among the unresolved issues in the design of structural concrete reinforced with fiber reinforced composite (FRP) bars, the understanding of size effect in the reduction of the shear strength of deep beams without shear Reinforcement is of fundamental and practical sig- nificance. Size effect accrues primarily from the larger width of diagonal cracks as the effective depth is increased, and has been extensively documented in the case of steel reinforced concrete (RC) through a number of laboratory tests. In FRP RC, the lower longitudinal elastic modulus of the Flexural Reinforcement results in deeper and wider cracks. Yet, the calibration of any of the current semi-empirical design algorithms is based on test results of beams and one-way slabs with maximum effective depth of 360 mm, which is not representative of relevant large-scale applications. This paper presents and discusses the results of laboratory testing of large-size and scaled FRP RC beams without shear Reinforcement, having maximum effective depth of 147, 294 and 883 mm, and effective Reinforcement ratio of 0.12% and 0.24%. It is shown that the shear strength of the large-size specimens with less Flexural Reinforcement decreases on average by 55% compared with the smaller specimens. However, the conservativeness of the current de- sign algorithms generally offsets the size effect. The provisions of the UK Institution of Struc- tural Engineers (ISE) and the Italian National Research Council (CNR) provide the most accu- rate estimates, where the former yields more conservative and consistent results.
Rasha T.s. Mabrouk - One of the best experts on this subject based on the ideXlab platform.
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Analysis of the punching behavior of RC flat slabs with horizontal and vertical shear Reinforcement
MATEC Web of Conferences, 2017Co-Authors: Rasha T.s. Mabrouk, Ali A. HegabAbstract:Punching failure is one of the major drawbacks of using flat slabs in the design of reinforced concrete structures. Punching shear analysis is very complicated which appears clearly in the large variation of the equations used by the different codes in calculating the punching shear capacity. There are many factors that affect the punching shear capacity of an element. This current research aims to investigate the contribution of two of these factors which are the horizontal Flexural Reinforcement, and the vertical shear Reinforcement in the form of stirrups. Following the experimental program conducted at the reinforced concrete laboratory of the Faculty of Engineering at Cairo University, Egypt and verification using the finite non-linear analysis software (ANSYS 15), good correlation was observed between the analytical models and their corresponding experimental data. This proves that ANSYS 15 allows for studying the punching behavior of the flat slab in more details which could not be monitored in the laboratory. As a result, a detailed parametric study as well as comparison with some design codes was conducted using thirteen full scale flat slab specimens in order to simulate real life problems. The specimens had a loaded span of 2000 mm and a total thickness of 250 mm. The variables under study were the Flexural Reinforcement ratio and stirrups spacing and diameter in order to further enhance the understanding of the behavior of flat slabs in punching.
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effect of Flexural and shear Reinforcement on the punching behavior of reinforced concrete flat slabs
alexandria engineering journal, 2017Co-Authors: Rasha T.s. Mabrouk, Amr Bakr, Hany F. AbdallaAbstract:Abstract Punching is one of the most important phenomena to be considered during the design of reinforced concrete flat slabs. Three main factors affect the punching behavior. These factors are concrete compressive strength, horizontal Flexural Reinforcement, and vertical shear Reinforcement in the form of stirrups, studs or other forms. This paper is part of an ongoing research program conducted at the concrete laboratory of the Faulty of Engineering, Cairo University to assess the contribution of horizontal Flexural Reinforcement and vertical shear Reinforcement on the punching behavior of reinforced concrete flat slabs. In the current research, seven half scale specimens are cast and tested. The specimens had dimensions of 1050 × 1050 mm and a total thickness of 100 mm. All specimens were connected to a square column of dimensions 150 × 150 mm and loaded at the four corners with a span 950 mm. The parameters considered in this research included spacing between vertical stirrups, width of the stirrups, number of stirrups branches and the ratio of the horizontal Flexural Reinforcement. During testing, ultimate capacity, steel strain, cracking pattern and deformation were recorded. The experimental results were analyzed and compared against values estimated from different international design codes.
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Effect of Flexural and shear Reinforcement on the punching behavior of reinforced concrete flat slabs
Alexandria Engineering Journal, 2017Co-Authors: Rasha T.s. Mabrouk, Amr Bakr, Hany F. AbdallaAbstract:Punching is one of the most important phenomena to be considered during the design of reinforced concrete flat slabs. Three main factors affect the punching behavior. These factors are concrete compressive strength, horizontal Flexural Reinforcement, and vertical shear Reinforcement in the form of stirrups, studs or other forms. This paper is part of an ongoing research program conducted at the concrete laboratory of the Faulty of Engineering, Cairo University to assess the contribution of horizontal Flexural Reinforcement and vertical shear Reinforcement on the punching behavior of reinforced concrete flat slabs. In the current research, seven half scale specimens are cast and tested. The specimens had dimensions of 1050 × 1050 mm and a total thickness of 100 mm. All specimens were connected to a square column of dimensions 150 × 150 mm and loaded at the four corners with a span 950 mm. The parameters considered in this research included spacing between vertical stirrups, width of the stirrups, number of stirrups branches and the ratio of the horizontal Flexural Reinforcement. During testing, ultimate capacity, steel strain, cracking pattern and deformation were recorded. The experimental results were analyzed and compared against values estimated from different international design codes. Keywords: Punching, Flat slabs, Flexural Reinforcement, Shear Reinforcement, Crack pattern, Ductilit
Hany F. Abdalla - One of the best experts on this subject based on the ideXlab platform.
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effect of Flexural and shear Reinforcement on the punching behavior of reinforced concrete flat slabs
alexandria engineering journal, 2017Co-Authors: Rasha T.s. Mabrouk, Amr Bakr, Hany F. AbdallaAbstract:Abstract Punching is one of the most important phenomena to be considered during the design of reinforced concrete flat slabs. Three main factors affect the punching behavior. These factors are concrete compressive strength, horizontal Flexural Reinforcement, and vertical shear Reinforcement in the form of stirrups, studs or other forms. This paper is part of an ongoing research program conducted at the concrete laboratory of the Faulty of Engineering, Cairo University to assess the contribution of horizontal Flexural Reinforcement and vertical shear Reinforcement on the punching behavior of reinforced concrete flat slabs. In the current research, seven half scale specimens are cast and tested. The specimens had dimensions of 1050 × 1050 mm and a total thickness of 100 mm. All specimens were connected to a square column of dimensions 150 × 150 mm and loaded at the four corners with a span 950 mm. The parameters considered in this research included spacing between vertical stirrups, width of the stirrups, number of stirrups branches and the ratio of the horizontal Flexural Reinforcement. During testing, ultimate capacity, steel strain, cracking pattern and deformation were recorded. The experimental results were analyzed and compared against values estimated from different international design codes.
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Effect of Flexural and shear Reinforcement on the punching behavior of reinforced concrete flat slabs
Alexandria Engineering Journal, 2017Co-Authors: Rasha T.s. Mabrouk, Amr Bakr, Hany F. AbdallaAbstract:Punching is one of the most important phenomena to be considered during the design of reinforced concrete flat slabs. Three main factors affect the punching behavior. These factors are concrete compressive strength, horizontal Flexural Reinforcement, and vertical shear Reinforcement in the form of stirrups, studs or other forms. This paper is part of an ongoing research program conducted at the concrete laboratory of the Faulty of Engineering, Cairo University to assess the contribution of horizontal Flexural Reinforcement and vertical shear Reinforcement on the punching behavior of reinforced concrete flat slabs. In the current research, seven half scale specimens are cast and tested. The specimens had dimensions of 1050 × 1050 mm and a total thickness of 100 mm. All specimens were connected to a square column of dimensions 150 × 150 mm and loaded at the four corners with a span 950 mm. The parameters considered in this research included spacing between vertical stirrups, width of the stirrups, number of stirrups branches and the ratio of the horizontal Flexural Reinforcement. During testing, ultimate capacity, steel strain, cracking pattern and deformation were recorded. The experimental results were analyzed and compared against values estimated from different international design codes. Keywords: Punching, Flat slabs, Flexural Reinforcement, Shear Reinforcement, Crack pattern, Ductilit
James K. Wight - One of the best experts on this subject based on the ideXlab platform.
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Flexurally-triggered punching shear failure of reinforced concrete slab–column connections reinforced with headed shear studs arranged in orthogonal and radial layouts
Engineering Structures, 2016Co-Authors: Thai X. Dam, James K. WightAbstract:Abstract Shear strength of reinforced concrete slab–column connections can be increased through the use of headed shear studs. To reduce interference with slab Flexural Reinforcement, stud rails are often placed in an orthogonal layout. In this layout, no stud rail is placed in regions extending from the corners of a column, as opposed to stud placement in a radial layout. Some experiments have found the absence of radial stud rails could lead to premature shear failure at slab–column connections. This problem may not have been noticeable in experiments that tested slabs with either short-spans or with a high Flexural Reinforcement ratio. This paper presents an experimental study to evaluate the effectiveness of these stud layouts in slab–column connections whose slabs have relatively low Flexural Reinforcement ratios. Three full-scale slab–column connections that represent a flat plate structure with 25 ft (7620 mm) spans were tested. All three specimens had an identical Flexural design, in which the Reinforcement ratio was 0.8%. One specimen was built without shear Reinforcement, and the remaining two specimens were reinforced with shear studs in either a radial or orthogonal layout. For the specimens with shear studs, calculated shear strengths were higher than their estimated Flexural strengths.
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Flexurally triggered punching shear failure of reinforced concrete slab column connections reinforced with headed shear studs arranged in orthogonal and radial layouts
Engineering Structures, 2016Co-Authors: Thai X. Dam, James K. WightAbstract:Abstract Shear strength of reinforced concrete slab–column connections can be increased through the use of headed shear studs. To reduce interference with slab Flexural Reinforcement, stud rails are often placed in an orthogonal layout. In this layout, no stud rail is placed in regions extending from the corners of a column, as opposed to stud placement in a radial layout. Some experiments have found the absence of radial stud rails could lead to premature shear failure at slab–column connections. This problem may not have been noticeable in experiments that tested slabs with either short-spans or with a high Flexural Reinforcement ratio. This paper presents an experimental study to evaluate the effectiveness of these stud layouts in slab–column connections whose slabs have relatively low Flexural Reinforcement ratios. Three full-scale slab–column connections that represent a flat plate structure with 25 ft (7620 mm) spans were tested. All three specimens had an identical Flexural design, in which the Reinforcement ratio was 0.8%. One specimen was built without shear Reinforcement, and the remaining two specimens were reinforced with shear studs in either a radial or orthogonal layout. For the specimens with shear studs, calculated shear strengths were higher than their estimated Flexural strengths.
Su-min Kang - One of the best experts on this subject based on the ideXlab platform.
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punching shear behavior of shear reinforced slab column connection with varying Flexural Reinforcement
International Journal of Concrete Structures and Materials, 2019Co-Authors: Jae-ick Jang, Su-min KangAbstract:The effects of Flexural Reinforcement and shear Reinforcement on the punching shear strength of slab–column connections are analyzed in this study. For the study, six slab–column connection specimens were constructed with varying Flexural Reinforcement and shear Reinforcement, and were subjected to gravity load tests. Experimental results showed that all specimens were destroyed by punching failure, and that the slab–column connection behaved differently depending on the amount of shear Reinforcement and Flexural Reinforcement. Particularly, the Flexural Reinforcement in the slab–column connection improved the punching strength of the specimens with or without shear Reinforcement. In addition, in this study, a design formula that considers the Flexural Reinforcement ratio in the calculation of the punching shear strength of the shear reinforced slab–column connection was proposed and was verified using experimental results and existing test data.
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Punching Shear Behavior of Shear Reinforced Slab–Column Connection with Varying Flexural Reinforcement
International Journal of Concrete Structures and Materials, 2019Co-Authors: Jae-ick Jang, Su-min KangAbstract:The effects of Flexural Reinforcement and shear Reinforcement on the punching shear strength of slab–column connections are analyzed in this study. For the study, six slab–column connection specimens were constructed with varying Flexural Reinforcement and shear Reinforcement, and were subjected to gravity load tests. Experimental results showed that all specimens were destroyed by punching failure, and that the slab–column connection behaved differently depending on the amount of shear Reinforcement and Flexural Reinforcement. Particularly, the Flexural Reinforcement in the slab–column connection improved the punching strength of the specimens with or without shear Reinforcement. In addition, in this study, a design formula that considers the Flexural Reinforcement ratio in the calculation of the punching shear strength of the shear reinforced slab–column connection was proposed and was verified using experimental results and existing test data.
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Shear Strength of Composite Beams with Dual Concrete Strengths
ACI Structural Journal, 2016Co-Authors: Chul-goo Kim, Hong-gun Park, Geon-ho Hong, Su-min KangAbstract:Currently, in precast concrete constructions, precast and cast-in-place concrete with different concrete strengths are used in a composite structural member. However, current design codes are not obvious for calculating the vertical shear strength of PC-CIP composite members using dual concrete strengths. In the present study, shear strength of composite beams using dual concrete compressive strengths (24MPa, 60MPa) was tested. The test variables were the section area ratio of two type concretes, Flexural Reinforcement ratio, and shear span-to-depth ratio.