Aci Structural Journal 

About: Aci Structural Journal is an academic journal published by American Concrete Institute. The journal publishes majorly in the area(s): Flexural strength & Shear strength. It has an ISSN identifier of 0889-3241. Over the lifetime, 3182 publications have been published receiving 109740 citations. The journal is also known as: Structural journal & American Concrete Institute structural journal.

Shear Strengthening of Reinforced Concrete Beams Using Epoxy-Bonded FRP Composites

Abstract: The paper deals with the application of fiber reinforced polymer (FRP) laminates or fabrics as shear strengthening materials for reinforced concrete beams. The study aims at increasing the experimental database on shear strengthening of concrete using composites and, most importantly, developing an analytical model for the design of such members within the framework of modern code formats, based on ultimate limit states. The experimental part of the study involved testing of eleven concrete beams, strengthened in shear with carbon FRP at various area fractions and fiber configurations, while the analytical part resulted in a model for the contribution of FRP to shear capacity in analogy with steel stirrups, with an effective FRP strain that decreases with increasing FRP axial rigidity. It is shown that the effectiveness of the technique increases almost linearly with the FRP axial rigidity and reaches a maximum, beyond which it varies very little.

Simplified Modified Compression Field Theory for Calculating Shear Strength of Reinforced Concrete Elements

Abstract: In this article, the authors propose a simplified MCFT (modified compression field theory) and demonstrate that this simplified MCFT is capable of predicting the shear strength of a wide range of reinforced concrete (RC) elements with almost the same accuracy as the full theory. The authors summarize the results of over 100 pure shear tests on reinforced concrete panels. The ACI approach for predicting shear strength as the sum of a diagonal cracking load and a 45-degree truss model predicts the strength of these panels poorly, with an average experimental-over-predicted shear strength ratio of 1.40 with a coefficient of variation of 46.7%. The modified compression field theory (MCFT), developed in the 1980s, can predict the shear strength of these panels with an average shear strength ratio of 1.01 and a coefficient of variation (COV) of only 12.2%. The authors contend that their new, simplified method gives an average shear strength ratio of 1.11 with a COV of 13.0%. They demonstrate the application of this new simplified method to panels with numerical examples. They conclude that, on many occasions, a full load-deformation analysis is not needed and this quick calculation of shear strength is appropriate and useful.

Triaxial failure criterion for concrete and its generalization

Abstract: The authors present a failure criterion that describes the triaxial strength of concrete in terms of three independent stress invariants. Its geometric representation in principal stress space is convex and smooth and is characterized by two parabolic meridians and a deviatoric section that changes from triangular to circular shape with increasing confinement. The three-parameter description is calibrated from elementary strength data of uniaxial compression and uniaxial tension, as well as equibiaxial compression experiments. The failure criterion is verified with different biaxial and triaxial strength data on plain concrete. Finally, the failure criterion is generalized to a format that includes the standard strength hypotheses of Huber-Mises, Drucker-Prager, Rankine, Mohr-Coulomb, and Leon as special cases.

Deformations of Reinforced Concrete Members at Yielding and Ultimate

Abstract: The inelastic deformation capacity of reinforced concrete (RC) members is important for the resistance of RC structures to imposed deformations, and especially so for seismic loads as earthquake-resistant design relies on the ability of RC members to develop (cyclic) deformations well beyond elastic limits without significant loss of load-carrying capacity. This study develops expressions for the ultimate deformation capacity and for the deformation at yielding of RC members in terms of their geometric and mechanical characteristics. Such expressions are essential for the application of displacement-based procedures for earthquake-resistant design of new RC structures and for seismic evaluation of old ones. They are also essential for a realistic estimation of the effective elastic stiffness of cracked RC members and structures, which is important for the calculation of seismic force and deformation demands.