ABOUT THE 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.

International Concrete Abstracts Portal

Showing 1-5 of 417 Abstracts search results

Document: 

SP-346_09

Date: 

January 1, 2021

Author(s):

Christopher Gamache, Ananda Bergeron, and Pooya Farahbakhsh

Publication:

Symposium Papers

Volume:

346

Abstract:

The intent of this paper is to provide an illustrative example of a municipal bridge replacement design project utilizing fiber reinforced polymer materials approved for use by the Florida Department of Transportation. Specifically this paper describes the design of the Nathaniel J. Upham (40th Avenue NE) Bridge replacement project and illustrates the application of carbon fiber reinforced polymer (CFRP) prestressing tendons and glass fiber reinforced polymer (GFRP) reinforcing bars in both precast and cast-in-place concrete elements. Due to the structure’s high level of exposure in the extremely aggressive environment, the design for the replacement bridge focused on concrete elements that were durable and resilient to the effects of corrosion in those conditions. Prestressed and castin- place concrete elements with GFRP and CFRP reinforcement and prestressing tendons were utilized for the primary structural elements with direct exposure to salt water. In addition, link slabs with GFRP reinforcing were utilized at each intermediate bent to improve the bridge’s performance. The design of the bridge elements followed the Florida Department of Transportation’s design guidelines and requirements. The bridge replacement project is currently at the completion of the design phase and is scheduled to be advertised in the early summer of 2020 with the start of construction anticipated in the fall of 2020.


Document: 

SP-346_07

Date: 

January 1, 2021

Author(s):

Joseph Losaria, Steven Nolan, Andra Diggs II, and David Hartman

Publication:

Symposium Papers

Volume:

346

Abstract:

This case study highlights the use of Fiber Reinforced Polymer (FRP) materials on the US 41 Highway Bridge over North Creek in Sarasota County near the Florida Gulf Coast. Design and construction involved the use of Glass-FRP (GFRP) reinforcement on the cast-in-place (CIP) concrete flat slab superstructure, Carbon-FRP (CFRP) prestressing strands on the concrete piles, and GFRP reinforced precast panels for the substructure combining a bridge bearing abutment and retaining wall system. The application of FRP prestressing and reinforcing is promoted by the Florida Department of Transportation (FDOT) under their Transportation Innovation Challenge initiative. Soldier-pile retaining walls are a commonly used system in southeastern US coastal states, but the incorporation of innovative materials such as CFRP-prestressing for piles and GFRP-reinforcing for concrete panels is not yet widespread. Comparison of lateral stability results of this wall system during construction and in the final condition is discussed. In addition, to describing the preferred FRP-PC/RC solution adopted for this project, a comparison is provided to a recently completed adjacent bridge that utilized a conventional carbon-steel PC soldier-pile and RC precast panel wall system. A further comparison is presented for the design and cost of the wall system based on the project design criteria (ACI 440.1R, ACI 440.4R, and 2009 AASHTO LRFD Bridge Design Guide Specifications for GFRPReinforced Concrete, 1st Edition) with the refinements and savings possible under the newer editions. Finally, the life-cycle cost, durability and environmental benefits from the use of the innovative CFRP and GFRP reinforcing systems in this type of traditional wall system, are identified for typical urban coastal areas with extremely aggressive conditions, congested access, and challenging environmental constraints.


Document: 

SP343

Date: 

November 3, 2020

Author(s):

fib and ACI

Publication:

Symposium Papers

Volume:

343

Abstract:

The first international FRC workshop supported by RILEM and ACI was held in Bergamo (Italy) in 2004. At that time, a lack of specific building codes and standards was identified as the main inhibitor to the application of this technology in engineering practice. The workshop aim was placed on the identification of applications, guidelines, and research needs in order for this advanced technology to be transferred to professional practice. The second international FRC workshop, held in Montreal (Canada) in 2014, was the first ACI-fib joint technical event. Many of the objectives identified in 2004 had been achieved by various groups of researchers who shared a common interest in extending the application of FRC materials into the realm of structural engineering and design. The aim of the workshop was to provide the State-of-the-Art on the recent progress that had been made in term of specifications and actual applications for buildings, underground structures, and bridge projects worldwide. The rapid development of codes, the introduction of new materials and the growing interest of the construction industry suggested presenting this forum at closer intervals. In this context, the third international FRC workshop was held in Desenzano (Italy), four years after Montreal. In this first ACI-fib-RILEM joint technical event, the maturity gained through the recent technological developments and large-scale applications were used to show the acceptability of the concrete design using various fibre compositions. The growing interests of civil infrastructure owners in ultra-high-performance fibre-reinforced concrete (UHPFRC) and synthetic fibres in structural applications bring new challenges in terms of concrete technology and design recommendations. In such a short period of time, we have witnessed the proliferation of the use of fibres as structural reinforcement in various applications such as industrial floors, elevated slabs, precast tunnel lining sections, foundations, as well as bridge decks. We are now moving towards addressing many durability-based design requirements by the use of fibres, as well as the general serviceability-based design. However, the possibility of having a residual tensile strength after cracking of the concrete matrix requires a new conceptual approach for a proper design of FRC structural elements. With such a perspective in mind, the aim of FRC2018 workshop was to provide the State-of-the-Art on the recent progress in terms of specifications development, actual applications, and to expose users and researchers to the challenges in the design and construction of a wide variety of structural applications. Considering that at the time of the first workshop, in 2004, no structural codes were available on FRC, we have to recognize the enormous work done by researchers all over the world, who have presented at many FRC events, and convinced code bodies to include FRC among the reliable alternatives for structural applications. This will allow engineers to increasingly utilize FRC with confidence for designing safe and durable structures. Many presentations also clearly showed that FRC is a promising material for efficient rehabilitation of existing infrastructure in a broad spectrum of repair applications. These cases range from sustained gravity loads to harsh environmental conditions and seismic applications, which are some of the broadest ranges of applications in Civil Engineering. The workshop was attended by researchers, designers, owner and government representatives as well as participants from the construction and fibre industries. The presence of people with different expertise provided a unique opportunity to share knowledge and promote collaborative efforts. These interactions are essential for the common goal of making better and sustainable constructions in the near future. The workshop was attended by about 150 participants coming from 30 countries. Researchers from all the continents participated in the workshop, including 24 Ph.D. students, who brought their enthusiasm in FRC structural applications. For this reason, the workshop Co-chairs sincerely thank all the enterprises that sponsored this event. They also extend their appreciation for the support provided by the industry over the last 30 years which allowed research centers to study FRC materials and their properties, and develop applications to making its use more routine and accepted throughout the world. Their important contribution has been essential for moving the knowledge base forward. Finally, we appreciate the enormous support received from all three sponsoring organizations of ACI, fib and Rilem and look forward to paving the path for future collaborations in various areas of common interest so that the developmental work and implementation of new specifications and design procedures can be expedited internationally. June 2018 Bruno Massicotte, Fausto Minelli, Barzin Mobasher, Giovanni Plizzari


Document: 

SP-343_50

Date: 

October 1, 2020

Author(s):

Charron, J.P.; Desmettre, C.; Cantin Bellemare, E.

Publication:

Symposium Papers

Volume:

343

Abstract:

A cast-in-place reinforced concrete footbridge built in 1967 suffering from extensive concrete spalling and rebar corrosion needed to be replaced. The use of a steel Pony-Warren truss combined with thin precast UHPFRC slabs linked by short UHPFRC field-cast joints was selected to build an innovative, durable and aesthetic footbridge minimizing impact on traffic during construction. Material rationalization allowed respective reductions of 64 % and 91 % of concrete and rebar volumes in the slab in comparison to a conventional reinforced concrete slab. The design process was completed with non-linear finite element calculations to obtain an adequate behaviour of the UHPFRC slabs and joints at service and ultimate limit states. A full-size proof specimen was then tested under positive bending moment and confirmed being adequate and fulfilling all the design specifications. Construction of the precast slab was successful and required less time than a conventional slab. The long-term performance provided by the UHPFRC slab will be followed up in the next decades.


Document: 

SP-343_48

Date: 

October 1, 2020

Author(s):

Redaelli, D.; Nseir, J.Y.

Publication:

Symposium Papers

Volume:

343

Abstract:

This paper presents the results of a numerical study carried out by the authors to better understand the structural behavior of prestressed beams with web openings and to identify numerical modelling techniques that allow to adequately predict such behavior. Ultra-High Performance Fibre Reinforced Concrete (UHPC) beams are considered, with a focus on shear-controlled failure modes. For all the beams considered in this study, prestressing is used to resist the main bending moment. However, no other reinforcement is added to the beams, in order to emphasize the structural contribution of the fibers and to focus on solutions that could be economically competitive for the precast industry. The results of non-linear simulations performed with existing finite elements codes are compared and validated against experimental results of tests carried out at the University of Applied Sciences of Western Switzerland. The main assumptions of the numerical simulations are discussed, as well as the results and the limits of the analysis.


12345...>>

Results Per Page 




Please enter this 5 digit unlock code on the web page.