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 # 02.01/07
The Offices 02 Building, One Central
Dubai World Trade Center Complex
Phone: +971.4.516.3208 & 3209
Chat with Us Online Now
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 185 Abstracts search results
April 1, 2020
Raymon W. Nickle and Yail J. Kim
With over 80 years of history, it is only in the last 20 years that the use of fiber reinforced polymer (FRP) materials has become feasible for bridge applications in part due to the ever increasing requirement to make structures last longer, with the current American Association of State Highway Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) Bridge Design Specifications requiring that structures be designed for a 75 year design life; but also in the development of cost effective production techniques, and the introduction of FRP materials, which bring the cost and strength of FRP materials closer to traditional steel reinforcement. Published documents provide comprehensive recommendations on design methodology, predictive equations, and recommendations for strength and service limits states. In this paper, the background of FRP-prestressed concrete bridges is discussed and trial bridges are designed. Research needs to advance the state of the art are identified and delineated.
March 1, 2020
Drew A. Kirkpatrick, Leonard M. Joseph, J. Ola Johansson, and C. Kerem Gulec
The distribution of forces through floor diaphragms is critical to the overall behavior and performance of buildings during both wind and seismic events. Simplified methods commonly employed by design engineers establish approximate magnitudes and distributions of inertial and transfer forces within floor diaphragms. Such methods can be appropriate for regular low-rise buildings without significant transfer forces. However, for design of complex structures with large stiffness discontinuities in vertical or horizontal directions, a more detailed investigation and modeling of diaphragm behavior is usually required. Common situations in high-rise projects include a tower stack meeting a podium base with supplemental shear walls and a tower stack meeting a grade-level slab enclosed by basement walls. Large diaphragm transfer forces typically occur at these levels of abrupt stiffness changes. Using examples from recent projects and parametric studies following performance-based seismic design (PBSD) principles, this paper describes the use of strut-and-tie models in commercially available software (PERFORM-3D) to provide a better understanding of complex diaphragm behavior. Results can aid the designer in making decisions regarding floor thickness and reinforcing layout, including at chords and collectors. While the need for enhanced modeling techniques and understanding of diaphragm behavior has been highlighted by the increased use of PBSD, the findings presented in this paper may be applicable to projects based on traditional (code-based) approaches as well.
Xiaonian Duan, Andrea Soligon, Jeng Neo, and Anindya Dutta
The new Terminal 2 at the Tocumen International Airport in Panama, currently essentially completed, will increase the airport’s capacity to 25 million passengers per year. It has a doubly curved steel roof supported on reinforced concrete columns. The gravity force-resisting systems in the superstructure include long span precast and prestressed double tee decks, topped with cast-in-place concrete diaphragms and supported on a combination of unbonded post-tensioned girders and special reinforced concrete moment frame beams. The seismic force-resisting system includes special reinforced concrete moment frames and perimeter columns, special reinforced concrete shear walls and diaphragms, all detailed in accordance with ACI 318. Located in a region of moderately high seismic hazard, the building is classified as an essential facility and requires a non-conventional seismic design approach to maintain operational continuity and to protect life. Adopting the performance-based seismic design methodology and the capacity design principle, the structural engineering team designed an innovative reinforcement detail for developing ductile hinges at the top of the reinforced concrete columns to protect the structural steel roof which is designed to remain essentially elastic under MCE shaking. The structural engineering team’s design has been reviewed by internationally recognized experts and three independent peer review teams.
Mustafa K. Buniya, Andre R. Barbosa, and Siamak Sattar
A 160-foot (≈ 49 m) tall 12–story reinforced concrete special moment frame building is designed following ASCE 7-16 and ACI 318-14, and assessed using three Performance-Based Seismic Engineering (PBSE) standards and guidelines including ASCE/SEI 41, the Tall Buildings Initiative (TBI) guidelines for performance-based design of tall buildings, and the Los Angeles Tall Buildings Structural Design Council (LATBSDC) procedures. The assessments are performed at the combination of two performance and hazard levels including Collapse Prevention (CP) at the risk-targeted maximum considered earthquake (MCER) hazard level and Immediate Occupancy (IO) at a frequent ground motion level with 50 percent probability of exceedance in 30 years, i.e. serviceability performance level. Based on the recommendations of each of the three PBSE documents, nonlinear finite element models are implemented in OpenSees. Through nonlinear time-history response analyses, the finite element models are subjected to eleven ground motions that are selected following the ground motion selection recommendations in ASCE 7-16. Assessment results indicate that for the serviceability performance level, the code-compliant building meets the design requirements of the three PBSE documents for the inter-story drift ratio and inelastic deformation of the structural components. At the MCER hazard level, although the building essentially satisfies the design requirements for the peak inter-story drift ratios and inelastic deformation, the mean of the residual inter-story drift ratios as well as the envelope of the residual drift ratios do not meet the limits of the TBI and LATBSDC guidelines. The results indicate that the newly designed building meets the ASCE 41 acceptance criteria but does not meet the design requirements set in TBI and LATBSDC guidelines.
Saeed Fathali, Bret Lizundia, and Francisco Parisi
This paper summarizes the benefits and challenges of implementing performance-based seismic design (PBSD) for two concrete buildings of the Lower Sproul Plaza Redevelopment Project in one of the busiest areas of the UC Berkeley campus. The project included new construction of Eshleman Hall and the additions to Martin Luther King (MLK) Hall, and the seismic retrofit of the existing MLK Student Union as a result of the expansion. The peer-reviewed PBSD implemented three-dimensional nonlinear response history analyses at two levels of seismic hazard. The analytical simulations using pairs of near-fault ground motions, scaled to match the site-specific spectrum, were intended to establish the expected seismic behavior of the buildings under rare and frequent earthquakes. The choice of PBSD over code-prescriptive procedures was prompted by multiple layers of complexity of the project. Several challenges including those related to the horizontal and vertical irregularities, or connecting new and existing concrete buildings with different lateral force-resisting systems would have made a code-prescriptive design a cumbersome analytical endeavor without providing reliable insight about the expected seismic behavior of the buildings. The PBSD, however, proved a powerful framework to design for a reliably predictable seismic behavior with sufficient ductility, and a designated ductile hinge zones with sufficient confinement and shear capacity. The PBSD methodology also enabled the designers to avoid unnecessary conservatism to deal with the complexities, when designing drift- and acceleration-sensitive elements including the cladding system. Finally, the PBSD methodology allowed the design to consider all potential modes of failure of concrete elements retrofitted by FRP material including the debonding failure between FRP material and substrate.
Results Per Page
Please enter this 5 digit unlock code on the web page.