Earthquakes worldwide have clearly demonstrated the vulnerability of reinforced concrete members to degradation in shear strength when subjected to cyclic loading. Such degradation can lead to significant damage to the structure and, possibly, even collapse. With the advancement of performance-based earthquake engineering, where the response of the structure must be traced through all levels of damage, there is a significant need to accurately define the deformation capacity and shear strength for such members. This symposium publication represents an effort from researchers across the globe trying to address this challenging problem.
Although at the time of publication there are some methodologies that can be used in performance-based earthquake engineering, there is a significant need for improved methods better suited for these types of applications. Furthermore, one of the concerns often expressed by researchers is that test data used in the past to develop and calibrate existing models consisted of relatively small data sets. This problem is compounded by differences between experimental studies in aspects such as the type of load history used, the manner in which deformations were recorded during tests, and the definition of displacement and strength at failure.
The recent development of the PEER column database, hosted by the University of Washington, provided a valuable resource to overcome some of these problems. It presented researchers with a larger pool of data, which included the full hysteretic response of every column in the data set. Although this represented a very significant step forward, efforts of this kind should continue to improve the ability of researchers to calibrate and evaluate models for shear strength and deformation capacity.
A joint technical session was organized by Joint ACI-ASCE Committees 441, Reinforced Concrete Columns, and 445, Shear and Torsion, during the American Concrete Instituteβs Fall 2004 Convention in San Francisco, CA. The goal of the technical session was to showcase recent developments in this area, with the hope that continued discussion will lead to improved models that are suitable for performance-based engineering.
This symposium publication is a collection of technical articles presented at that meeting and represents an effort from Joint ACI-ASCE Committees 441 and 445 to continue the technical discussion on this topic
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Since the use of asbestos fibers is totally banned in the industrialized countries and discouraged in almost all countries, a large number of researchers around the world are working to obtain a replacement. Various forms of fabrics, meshes, and discrete fibers made of metal, mineral, polymeric, and naturally occurring materials have been investigated.
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
The design, analysis, and performance of structural concrete slabs under punching shear loading conditions are topics that have been studied extensively over many decades and are well documented in the literature. However, the majority of the work reported in these areas is generally related to conventional concrete slabs subjected to highly idealized loading conditions.
Structural engineers need to find new, innovative ways and methods to design new structures but also to strengthen existing infrastructure to ensure safety, resilience, and sustainability. These challenges can be addressed through the use of integrated systems and high-performance technologically advanced materials. We live in a new era of improved computational capabilities, advances in high-performance computing, numerical and experimental methods, and data-driven techniques, which give us broader access to larger and better data sets and analysis tools. These new advancements are essential to develop deeper insights into the structural behavior of concrete slabs under punching shear and to implement and analyze new materials and loading conditions.
This Special Publication presents recent punching shear research and insights relating to topics that have historically received less attention in the literature and/or are absent from existing codified design procedures. Topics addressed include: the usage and impacts of alternative/modern construction materials (new concrete and concrete-like materials, nonmetallic reinforcement systems, and combinations thereof) on slab punching shear resistance, novel shear reinforcement or strengthening systems, the influence of highly irregular/nonuniform loading and support conditions on slab punching shear, impact loading, new design and analysis techniques, and the study of the punching shear behavior of footings.
This Special Publication will be of interest to designers who are often faced with punching-related design requirements that fall outside of traditional research areas and existing code provisions, as well as for researchers who are performing research in related areas.
Perspectives from a broad and international group of authors are included in this Special Publication, relating to a variety of punching-related problems that occur in research and practice. In particular, researchers from the United States, Canada, Ecuador, the Netherlands, Italy, Brazil, Israel, Portugal, Spain, the United Arab Emirates, and Germany contributed to the articles in this Special Publications.
To exchange views on the new materials, tests, and analysis methods related to punching, Joint ASCE-ACI Committee 421, βDesign of Reinforced Concrete Slabs;β Joint ASCE-ACI Committee 445, βShear and Torsion;β and subcommittee ACI 445-C, βPunching Shear,β organized two sessions titled βPunching shear of concrete slabs: insights from new materials, tests, and analysis methodsβ at the ACI Spring Convention 2023 in San Francisco, CA. This Special Publication contains several technical papers from experts who presented their work at these sessions, in addition to papers submitted for publication only.
Co-editors Dr. Katerina Genikomsou, Dr. Trevor Hrynyk, and Dr. Eva Lantsoght are grateful for the contributions of the authors and sincerely value the time and effort of the authors in preparing the papers in this volume, as well as of the reviewers of the manuscripts.
Aikaterini Genikomsou, Trevor Hrynyk, and Eva Lantsoght
Co-editors
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
ACI Committees 441 β Reinforced Concrete Columns and 341A β Earthquake-Resistant Concrete Bridge Columns, Mohamed A. ElGawady
Columns are crucial structural elements in buildings and bridges. This Special Publication of the American Concrete Institute Committees 441 (Reinforced Concrete Columns) and 341A (Earthquake-Resistant Concrete Bridge Columns) presents the state-of-the-art on the structural performance of innovative bridge columns. The performance of columns incorporating high-performance materials such as ultra-high-performance concrete (UHPC), engineered cementitious composite (ECC), high-strength concrete, high-strength steel, and shape memory alloys is presented in this document. These materials are used in combination with conventional or advanced construction systems, such as using grouted rebar couplers, multi-hinge, and cross spirals. Such a combination improves the resiliency of reinforced concrete columns against natural and man-made disasters such as earthquakes and blast.
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Overall, in this Special Publication, authors from different backgrounds and geographical locations share their experiences and perspectives on the strength evaluation and design of concrete bridges using advanced computational analysis and load testing methods. Contributions were made from different regions of the world, including Canada, Italy, and the United States, and the technical papers were authored by experts at universities, government agencies, and private companies. The technical papers considered both advanced computational analysis and load testing methods for the strength evaluation and design of concrete bridges.
Sponsors: Sponsored by ACI Committees 342, Evaluation of Concrete and 343, Concrete Bridge Design (Joint ACI-ASCE)
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Publication information: fib Bulletin 95 is published as a tec is published as a technical report and is a collection of contributions to a workshop report and is a collection of contributions to a workshop that was co-sponsored by the fib and the and the American Concrete Institute American Concrete Institute (ACI). The authors have authors presented their presented their individual views. Although these contributions have not been discussed in any of the y of the fibβs working bodies, the subject matter is highly topical and believed to be of general interest to members of the al interest to members of the fib.
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
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
This Symposium Volume reports on the latest developments in the field of high strain rate mechanics and behavior of concrete subject to impact loads. This effort supports the mission of ACI Committee 370 βBlast and Impact Load Effectsβ to develop and disseminate information on the design of concrete structures subjected to impact, as well as blast and other short-duration dynamic loads. Concrete structures can potentially be exposed to accidental and malicious impact loads during their lifetimes, including those caused by ballistic projectiles, vehicular collision, impact of debris set in motion after an explosion, falling objects during construction and floating objects during tsunamis and storm surges. Assessing the performance of concrete structures to implement cost-effective and structurally-efficient protective measures against these extreme impacting loads necessitates a fundamental understanding of the high strain rate behavior of the constituent materials and of the characteristics of the local response modes activated during the event.
This volume presents fourteen papers which provide the reader with deep insight into the state-of-the-art experimental research and cutting-edge computational approaches for concrete materials and structures subject to impact loading. Invited contributions were received from international experts from Australia, Canada, China, Czech Republic, Germany, South Korea, Switzerland, and the United States. The technical papers cover a range of cementitious materials, including high strength and ultra-high strength materials, reactive powder concrete, fiber-reinforced concrete, and externally bonded cementitious layers and other coatings. The papers were
to be presented during two technical sessions scheduled for the ACI Spring 2020 Convention in Rosemont, Illinois, but the worldwide COVID-19 pandemic disrupted
those plans.
The editors thank the authors for their outstanding efforts to showcase their most current research work with the concrete community, and for their assistance, cooperation, and valuable contributions throughout the entire publication process. The editors also thank the members of ACI Committee 370, the reviewers, and the ACI staff for their generous support and encouragement throughout the preparation of this volume.
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
With increasing world population and urbanization, the depletion of natural resources and generation of waste materials is becoming a considerable challenge. As the number of humans has exceeded 7 billion people, there are about 1.1 billion vehicles on the road, with 1.7 billion new tires produced and over 1 billion waste tires generated each year. In the USA, it was estimated in 2011 that 10% of scrap tires was being recycled into new products, and over 50% is being used for energy recovery, while the rest is being discarded into landfills or disposed. The proportion of tires disposed worldwide into landfills was estimated at 25% of the total number of waste tires. Likewise, in 2013, Americans generated about 254 million tons of trash. They only recycled and composted about 87 million tons (34.3%) of this material. On average, Americans recycled and composted 1.51 pounds of individual waste generation of around 4.4 pounds per person per day. In 2011, glass accounted for 5.1 percent of total discarded municipal solid waste in the USA. Moreover, energy production and other sectors are generating substantial amounts of sludge, plastics and other post-consumer and industrial by-products. In the pursuit of its sustainability goals, the construction industry has a potential of beneficiating many such byproducts in applications that could, in some cases, outperform the conventional materials using virgin ingredients. This Special Publication led by the American Concrete Instituteβs Committee 555 on recycling is a contribution towards greening concrete through increased use of recycled materials, such as scrap tire rubber, post-consumer glass, reclaimed asphalt pavements, incinerated sludge ash, and recycled concrete aggregate. Advancing knowledge in this area should introduce the use of recycled materials in concrete for applications never considered before, while achieving desirable performance criteria economically, without compromising the long-term behavior of concrete civil infrastructure.
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
The purpose of this symposium and special publication is to recognize and honor Professor Amin Ghaliβs outstanding long-term dedication to the concrete industry. Dr. Ghali obtained his B.Sc. and M.Sc. degrees in Civil Engineering from Cairo University, Cairo, Egypt, respectively in 1950 and 1954, his Ph.D. from Leeds University, England in 1957. He spent ten years in engineering practice before joining at the University of Calgary, AB, Canada as a professor in 1966. Dr. Ghali has developed the revolutionary, multi-patented and globally used, headed-stud shear reinforcement systems for concrete flat slabs; he has been a consultant for a number of major international structures, including offshore structures, multi-story buildings, bridges, and tanks. Dr. Ghali authored over 300 papers and eight patents. In 15 editions and 6 translations, his books include: Structural Analysis Fundamentals (2022), Structural Analysis: A Unified Classical and Matrix Approach (2017), Circular Storage Tanks and Silos (2014), and Concrete Structures: Stresses and Deformations (2012).
Professor Ghali has served the industry in many ways, including his role as a voting member of ACI Committee 435, Deflection of Concrete Building Structures, 343, Concrete Bridge Design, and 421, Design of Reinforced Concrete Slabs. Jointly with associates at University of Calgary, his research on punching shear design and control of long-term deflection enables design of affordable concrete floors. Dr. Ghali served as expert, providing technical testimony, for a number of complicated engineering cases. Dr. Ghali received a number of teaching and research excellence awards over his long career, and was elected a Fellow of ACI, ASCE, CSCE, and CAE; in 2017, he received the Top 7 Over 70 Award for his outstanding continued research and engineering contributions.
The papers found in this SP publication encompass a broad overview on the important issues related to punching shear resistance and sustainable serviceability of flat plates from both a theoretical and design perspectives. These papers formed the basis of presentations made at the Amin Ghali Symposium on Design of Structural Concrete Slabs for Safety Against Punching and Excessive Deflection held at the ACI Fall 2020 Virtual Convention, on October 25, 2020. Twelve presentations were made in two sessions by those who have worked closely with Dr. Ghali in his areas of interest. The SP includes nine papers on design of concrete floors for punching and for serviceability. The sessions were sponsored by ACI Committee 421, Design of Reinforced Concrete Slabs.
All papers in this publication were reviewed by at least two recognized experts in accordance with ACI review procedures. Special thanks are extended to all who helped to make the two technical sessions and accompanying publication a success.
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
Code:
Content of this section is hidden, You must be registered and activate your account to see this content.
π½π½π½π½π½π½π½π½π½
See this link to read how you can remove this limitation:
π CLICK HERE π
This document provides guidance on the selection of materials for concrete repair. An overview of the important properties of repair materials is presented as a guide for making an informed selection of the appropriate repair materials for specific applications and service conditions.