In today’s market, it is imperative to be knowledgeable and have an edge over the competition. ACI members have it…they are engaged, informed, and stay up to date by taking advantage of benefits that ACI membership provides them.
Read more about membership
Become an ACI Member
Founded in 1904 and headquartered in Farmington Hills, Michigan, USA, the American Concrete Institute is a leading authority and resource worldwide for the development, dissemination, and adoption of its consensus-based standards, technical resources, educational programs, and proven expertise for individuals and organizations involved in concrete design, construction, and materials, who share a commitment to pursuing the best use of concrete.
ACI World Headquarters
38800 Country Club Dr.
Farmington Hills, MI
ACI Middle East Regional Office
Second Floor, Office #207
The Offices 2 Building, One Central
Dubai World Trade Center Complex
Phone: +971.4.516.3208 & 3209
ACI Resource Center
Feedback via Email
Home > Publications > International Concrete Abstracts Portal
The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.
Showing 1-5 of 69 Abstracts search results
December 1, 2023
Zhenwen Xu and Dongming Yan
External bonding with fiber-reinforced polymer (FRP) offers a
potential solution to mitigate the detrimental effects caused by
load impact and corrosion, which can weaken the bond strength
of reinforced concrete structures. However, existing models need
to be improved in addressing the FRP confinement mechanism and
failure modes. As a solution, the proposed model employs stress
intensity factor (SIF)-based criteria to determine the internal pressure exerted on the steel-concrete interface during various stages of comprehensive concrete cracking. Critical parameters are evaluated using weight function theory and a finite element model.
A bond-slip model is introduced for the FRP-concrete interface
and reasonable assumptions on failure plane characteristics. The
internal pressure model employed demonstrates that FRP confinement has the ability to generate dual peaks in stress distribution and modify their magnitude as the confinement level increases. The proposed predictive model demonstrates superior performance in failure modes, test methods, and wrap methods for assessing bond strength with FRP confinement. The accuracy of this model is indicated by an integral absolute error (IAE) of 9.6% based on 125 experimental data, surpassing the performance of the other
three existing models. Moreover, a new confinement parameter
is introduced and validated, showing an upper bound of 0.44 for
enhancing FRP bond strength. Additionally, a general expression
validating the bond strength model with FRP confinement is established, allowing for the prediction of bond length.
November 1, 2022
Juan Carlos Vivas and Raúl Zerbino
Impact resistance is an outstanding characteristic of fiber-reinforced concrete (FRC). To evaluate this property, many
methods have been designed. The most widespread test is the one proposed by ACI Committee 544. This test has stood out due to its speed and simplicity; nevertheless, the high dispersion in its results has made it unreliable. Recently, the authors have designed a new method based on the application of growing impact loads (GIL). It is simple, economical, and allows for the evaluation of FRC impact behavior at cracking and after cracking, with most of the resulting parameters expressed in terms of energy. In this paper, results obtained by both methods are compared. Two FRC materials were
evaluated, the first incorporating 30 kg/m3 of steel fiber and the second 5 kg/m3 of a polymeric fiber. Results showed that the parameters from the GIL method were less variable (up to approximately 44%) and had acceptable coefficients of variation (<30%).
March 1, 2022
Alessandro P. Fantilli and Farmehr M. Dehkordi
Experimental research performed on fiber-reinforced cement-based composites made with polymeric aggregate and reinforced with recycled steel fibers is presented in this paper. In total, 18 concrete prisms were cast with a two-stage procedure: first, the fibers from end-of-life tires were put in the molds and, subsequently, they were covered by a cementitious grout containing fine (recycled or virgin) aggregate. The two-stage composites showed more than one crack and a deflection-hardening behavior in the post-cracking regime by performing three-point bending tests. Moreover, both flexural and compressive strength increased with the fiber volume fraction. Thus, if the content of recycled materials is suitably selected, the ecological and mechanical performances of the two-stage composites improve and become similar to those of one-stage fiber-reinforced concrete made with only virgin components.
November 1, 2021
Joseph J. Assaad and Kamal H. Khayat
Fiber-reinforced high-strength grout (HSG) can secure exceptional mechanical properties; yet, case studies show that the interfacing layer to the existing substrate can be particularly vulnerable when used in specialty repair, precast, and retrofitting applications. Polymeric latex materials such as styrene-butadiene rubber (SBR) and acrylic ester (AE) are often incorporated to improve the bond properties and ensure monolithic behavior of the composite system. This paper assesses the concurrent effects of using steel fibers (SFs) and polymeric latexes on the flow and rheology of HSG, including their impact on mechanical properties and bond to existing concrete. The SF content varied from 0 to 5% by volume, while the mixing water was replaced by 10 to 20% of latex. Test results showed that the rheological properties of HSG increased with latex inclusion, given the coalescence of watersoluble polymers in the cementitious matrix that increased the viscosity of the interstitial liquid phase. The viscosity was aggravated with the addition of SF that accentuates the tendency of fiber grouping and interference between solid particles to hinder the ease of flow. The compressive strength slightly decreased when part of the mixing water was replaced by SBR or AE. Yet, in contrast, the flexural properties and pulloff bond strength were remarkably improved, which can be relevant to guarantee the integrity and monolithic behavior of the repair application.
September 1, 2021
Ahmed G. Bediwy and Ehab F. El-Salakawy
This study aims at assessing the long-term bond behavior of headed-end glass fiber-reinforced polymer (GFRP) bars to basalt fiber-reinforced cementitious composite (BFRCC) exposed to 300 consecutive freezing-and-thawing cycles, followed by 75 cycles of wetting and drying, mimicking successive winter and summer seasons. A total of 85 pullout specimens reinforced with recently developed basalt fiber pellets and steel fibers were tested. The durability of the specimens was quantified in terms of visual analysis, residual compressive strength, relative dynamic modulus of elasticity, as well as the residual pullout capacity. The addition of fibers was capable of retaining approximately 90% of the pullout capacity for specimens exposed to harsh conditions owing to the restriction of cracks in the fiber-reinforced cementitious composites. Therefore, the results confirmed the suitability of steel-free reinforcement systems for long-term application under severe freezing-and-thawing and wetting-and-drying environments.
Results Per Page