Connections in Concrete

A special issue of CivilEng (ISSN 2673-4109). This special issue belongs to the section "Structural and Earthquake Engineering".

Deadline for manuscript submissions: closed (30 April 2021) | Viewed by 53076

Special Issue Editor


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Guest Editor
Lyles School of Civil Engineering, Purdue University, West Lafayette, IN 47907-2051, USA
Interests: performance based design of RC structures; static and dynamic testing of RC structures and sub-assemblages; seismic retrofitting of structures with innovative techniques; seismic behavior of cast-in and post-installed anchors in concrete; anchorages with supplementary reinforcement; numerical modeling of structures under seismic loads; modeling of anchorages for interaction between structure and equipment; impact behavior of reinforced concrete structures; fracture mechanics of concrete structures; modeling of bond between reinforcement and concrete; performance of RC structures subjected to fire loads; structural applications of new concrete based materials
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Special Issue Information

Dear Colleagues,

Connections in a concrete structure are established either in the form of anchors (or fasteners) connecting structural or nonstructural components to the structure, or in the form of reinforcement embedded in concrete or as a part of steel–concrete composite construction. To ensure structural integrity, it is essential to form a reliable connection between steel and concrete. A well-performing anchorage (fastening) is a must to ensure the interaction between the components connected to the structure and the structure itself. The required flow of forces from concrete to steel and vice versa is established through a sufficient bond between reinforcement and concrete. The anchorage zones are crucial for desirable interaction between the concrete and steel structural members in a composite construction. Thus, in principle, the integrity of the entire structure relies heavily on the connections between steel and concrete.

With the advancement in production technologies, new products such as post-installed anchors, anchor channels, high-strength reinforcing bars, nonmetallic reinforcement, etc. are being developed, and it is essential to verify their performance in concrete. Similarly, the compatibility of newly developed concrete-based materials such as high-performance concrete, fiber-reinforced concrete, geopolymer concrete, etc. with the anchorages and reinforcement must be verified.

Practical and innovative solutions are needed for connections in real-life situations, and corresponding reliable design models are needed. In particular, the design models for anchorages are rather limited in scope, and many design issues need to be addressed. Some of these include various geometric configurations, anchorages under seismic loading, anchorages with supplementary reinforcement, anchor channels under different loading combinations, fatigue behavior, long-term performance, influence of corrosion on performance of anchorages, anchorages under extreme loading, etc. Not only is experimental research needed to answer these questions, but new numerical modeling approaches also need to be developed for deeper understanding of the topics.

Another very important aspect is the harmonization of design methods. For example, post-installed reinforcement can be designed either as an anchorage following the principles of fastening technology or as a reinforcing bar following the principles of reinforced concrete. However, the two principles generally lead to very different design solutions. Similarly, the fastening technology principles require the base plate connecting different anchors to be rigid and stiff elastic, while composite construction principles recommend designing the base plate for yielding. These approaches need harmonization.

Often, the performance of structures under extreme hazards of earthquakes, impact or fire is dominated by the performance of its connections. Reliable design of connections against such hazards calls for performance-based approaches where the compatibility requirements between different components are accounted for.

Every type of strengthening needs a certain type of anchorage. The performance of the strengthening depends largely on the performance of the anchorage itself. Very high and challenging demands are imposed on the anchorages used in strengthening (e.g., seismic strengthening). Some of these include high forces, large crack widths, combined load and crack cycling, limited area and depth to develop the required resistance, limited access due to existing reinforcement, etc. Innovative strengthening methods along with anchorage techniques need to be developed that would allow the strengthening to serve its desired function and ensure the safe functioning of the structure.

The proposed Special Issue targets the above-mentioned issues in the field of connections in concrete and offers a platform to researchers and experts worldwide to showcase their work. Currently, there is no journal that is dedicated to the problems of connections in concrete, and therefore, publications in this field are often directed to journals that provide a more general scope. In the experience of the proposer, it is often quite difficult to find a suitable journal to present the work in the field of connections in concrete. This issue would offer a new chance to hundreds of researchers working in the field of connections in concrete to publish their work. Additionally, since connections in concrete are, in general, not widely covered in classroom teaching, practitioners and consultants often look for innovative answers and solutions to their problems. This issue would offer them a place to look for such innovative solutions.

  • Cast-in anchorages including anchor channels
  • Bond between reinforcement and concrete
  • Anchorages in composite construction
  • Anchorages in structural strengthening
  • Post-installed mechanical anchors
  • Adhesive anchors and post-installed reinforcement
  • Bond of special reinforcement in concrete
  • Anchorages in special concretes
  • Numerical modeling of anchorages and bond
  • Code based design models
  • Performance based approaches for anchorages
  • Connections under seismic actions
  • Connections under extreme situations (fire, impact)
  • Connections under special actions

Dr. Akanshu Sharma
Guest Editor

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Published Papers (15 papers)

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Research

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24 pages, 8701 KiB  
Article
Influence of Different Fiber Dosages on the Behaviour of Façade Anchors in High-Performance Concrete
by Szymon Grzesiak, Matthias Pahn, Milan Schultz-Cornelius and Nora Susanne Bies
CivilEng 2021, 2(3), 556-579; https://doi.org/10.3390/civileng2030031 - 13 Jul 2021
Cited by 2 | Viewed by 5585
Abstract
The behaviour of façade anchors in high performance fiber reinforced concrete (HPFRC) has not been investigated in sufficient detail in recent years. The regulations in the European Technical Approvals also do not fully describe the load-bearing capacity of anchor systems. Due to the [...] Read more.
The behaviour of façade anchors in high performance fiber reinforced concrete (HPFRC) has not been investigated in sufficient detail in recent years. The regulations in the European Technical Approvals also do not fully describe the load-bearing capacity of anchor systems. Due to the increase in the production of HPFRC elements, it is necessary to analyse the impact of added fibers in the concrete composition on the behaviour of anchors. In particular, the behaviour of anchors in filigree façade elements, which is one of the main application areas of the programme of polypropylene (PP) fiber-reinforced concrete, is therefore analysed. With a sufficient content of PP fibers surrounding the steel anchors oriented in an optimal direction, the fibers may enhance both the load-bearing capacity of anchors and the ductility of concrete. However, unfavourable effects on the installation process or even on the load-bearing capacity may also occur due to unfavourable fiber orientation. Therefore, tensile and punching tests were carried out in uncracked concrete with different types of anchor systems containing a tension anchor and an adjustable spacer bolt. The PP fiber content of the concrete component varied during the tests. Full article
(This article belongs to the Special Issue Connections in Concrete)
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21 pages, 5073 KiB  
Article
Numerical and Experimental Investigation on Concrete Splitting Failure of Anchor Channels
by Anton Bogdanić, Daniele Casucci and Joško Ožbolt
CivilEng 2021, 2(2), 502-522; https://doi.org/10.3390/civileng2020028 - 18 Jun 2021
Cited by 2 | Viewed by 2941
Abstract
Concrete splitting failure due to tension load can occur when fastening systems are located close to an edge or corner of a concrete member, especially in thin members. This failure mode has not been extensively investigated for anchor channels. Given the current trend [...] Read more.
Concrete splitting failure due to tension load can occur when fastening systems are located close to an edge or corner of a concrete member, especially in thin members. This failure mode has not been extensively investigated for anchor channels. Given the current trend in the construction industry towards more slender concrete members, this failure mode will become more and more relevant. In addition, significantly different design rules in the United States and Europe indicate the need for harmonization between codes. Therefore, an extensive numerical parametric study was carried out to evaluate the influence of member thickness, edge distance, and anchor spacing on the capacity of anchor channels in uncracked and unreinforced concrete members. One of the main findings was that the characteristic edge distance depends on the member thickness and can be larger than 3hef (hef = embedment depth) for thin members. Based on the numerical and experimental test results, modifications of the design recommendations for the splitting failure mode are proposed. Overall, the authors recommend performing the splitting verification separately from the concrete breakout to design anchor channels in thin members more accurately. Full article
(This article belongs to the Special Issue Connections in Concrete)
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17 pages, 4188 KiB  
Article
Analytical Investigation of Tension Loaded Deformed Rebar Anchors in Concrete
by Sandip Chhetri and Rachel A. Chicchi
CivilEng 2021, 2(2), 442-458; https://doi.org/10.3390/civileng2020025 - 4 Jun 2021
Cited by 1 | Viewed by 2912
Abstract
Experimental testing of deformed rebar anchors (DRAs) has not been performed extensively, so there is limited test data to understand their failure behavior. This study aims to expand upon these limited tests and understand the behavior of these anchors, when loaded in tension. [...] Read more.
Experimental testing of deformed rebar anchors (DRAs) has not been performed extensively, so there is limited test data to understand their failure behavior. This study aims to expand upon these limited tests and understand the behavior of these anchors, when loaded in tension. Analytical benchmark models were created using available test data and a parametric study of deformed rebar anchors was performed. Anchor diameter, spacing, embedment, and number of anchors were varied for a total of 49 concrete breakout simulations. The different failure modes of anchors were predicted analytically, which showed that concrete breakout failure is prominent in the DRA groups. The predicted concrete breakout values were consistent with mean and 5% fractile concrete capacities determined from the ACI concrete capacity design (CCD) method. The 5% fractile factor determined empirically from the simulation results was kc = 26. This value corresponds closely with kc = 24 specified in ACI 318-19 and ACI 349-13 for cast-in place anchors. The analysis results show that the ACI CCD formula can be conservatively used to design DRAs loaded in tension by applying a kc factor no greater than 26. Full article
(This article belongs to the Special Issue Connections in Concrete)
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11 pages, 7340 KiB  
Article
Anchor Plates Bonded on Reinforced Concrete: A Preliminary Experimental Investigation
by Andrea Nino Consiglio and Giovanni Muciaccia
CivilEng 2021, 2(2), 385-395; https://doi.org/10.3390/civileng2020021 - 19 May 2021
Viewed by 2195
Abstract
During the last decades, different technologies to anchor steel elements in concrete were proposed. The present work presents the results of a preliminary investigation of a new connection characterized by single steel plates that are directly bonded on concrete surfaces. The anchor response [...] Read more.
During the last decades, different technologies to anchor steel elements in concrete were proposed. The present work presents the results of a preliminary investigation of a new connection characterized by single steel plates that are directly bonded on concrete surfaces. The anchor response was experimentally investigated under both tension and shear actions. Specific conditions influencing the behavior of the bonded assembly were discussed, with particular reference to the presence of cracks and crack cycling in concrete. Full article
(This article belongs to the Special Issue Connections in Concrete)
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21 pages, 7107 KiB  
Article
Bidirectional Loading History for Seismic Testing of 3D Frame Joints
by Vinay Mahadik and Akanshu Sharma
CivilEng 2021, 2(2), 349-369; https://doi.org/10.3390/civileng2020019 - 3 May 2021
Cited by 3 | Viewed by 2971
Abstract
Beam-column-joints (BCJ) in reinforced concrete (RC) frames are known to be critical against seismic actions. Hence, several researchers have conducted related investigations. The loading history used in the experimental investigations must be a sufficiently accurate and conservative representation of seismic loading on the [...] Read more.
Beam-column-joints (BCJ) in reinforced concrete (RC) frames are known to be critical against seismic actions. Hence, several researchers have conducted related investigations. The loading history used in the experimental investigations must be a sufficiently accurate and conservative representation of seismic loading on the structure and should trigger all possible critical failure mechanisms in the subassembly. Presently, there is significant diversity in the loading histories used for seismic investigation of structural subassemblies. This paper intends to propose an optimum loading history for considering bidirectional (horizontal) seismic action on 3D-RC BCJ subassemblies. To this end, the available loading histories (unidirectional and bidirectional) for simulation of seismic loads on RC joint subassemblies are reviewed in the context of the demands they impose on the joints. Finite element modeling and analyses are used as a tool for investigating the response of 3D-BCJ subassembly under different bidirectional loading states. Full article
(This article belongs to the Special Issue Connections in Concrete)
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21 pages, 13136 KiB  
Article
Analytical Investigation on the Effect of Test Setup on Bond Strength
by Konstantinos Tsiotsias and Stavroula J. Pantazopoulou
CivilEng 2021, 2(1), 14-34; https://doi.org/10.3390/civileng2010002 - 1 Jan 2021
Cited by 4 | Viewed by 3602
Abstract
Experimental procedures used for the study of reinforcement to concrete bond have been hampered for a long time by inconsistencies and large differences in the obtained behavior, such as bond strength and mode of failure, depending on the specimen form and setup used [...] Read more.
Experimental procedures used for the study of reinforcement to concrete bond have been hampered for a long time by inconsistencies and large differences in the obtained behavior, such as bond strength and mode of failure, depending on the specimen form and setup used in the test. Bond is controlled by the mechanics of the interface between reinforcement and concrete, and is sensitive to the influences of extraneous factors, several of which underlie, but are not accounted for, in conventional pullout test setups. To understand and illustrate the importance of specimen form and testing arrangement, a series of computational simulations are used in the present work on eight distinct variants of conventional bar pullout test setups that are used routinely in experimental literature for the characterization of bond-slip laws. The resulting bond strength increase generated by unaccounted confining stress fields that arise around the bar because of the boundary conditions of the test setup is used to classify the tests with respect to their relevance with the intended use of the results. Of the pullout setups examined, the direct tension pullout test produced the most conservative bond strength results, completely eliminating the contributions from eccentricity and passive confinement. Full article
(This article belongs to the Special Issue Connections in Concrete)
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13 pages, 2569 KiB  
Article
Testing and Evaluation of Anchor Channels under Fatigue Loading
by Thilo Fröhlich and Dieter Lotze
CivilEng 2021, 2(1), 1-13; https://doi.org/10.3390/civileng2010001 - 24 Dec 2020
Cited by 1 | Viewed by 2933
Abstract
Cast-in anchor channels are used to connect steel components to concrete structures e.g., for elevators, cranes or machines, where repeated load cycles require verification against fatigue failure. The fatigue resistance of anchor channels may be determined by tests according to the interactive method, [...] Read more.
Cast-in anchor channels are used to connect steel components to concrete structures e.g., for elevators, cranes or machines, where repeated load cycles require verification against fatigue failure. The fatigue resistance of anchor channels may be determined by tests according to the interactive method, which provides a complete description of the S/N curve from one to infinite load cycles according to the current assessment document. This procedure differs from conventional fatigue concepts, which do not consider loads that are part of low cycle fatigue, but also question the general existence of an endurance limit. An alternative approach presented in this paper is based on the assumption that the S/N curve can be approximated by a bilinear function. The procedure for the evaluation of fatigue tests on anchor channels embedded in concrete is described. A comparison with the current qualification criteria is given by a test example to discuss the applicability of the proposed method. Full article
(This article belongs to the Special Issue Connections in Concrete)
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17 pages, 3088 KiB  
Article
Material-Dependent Shear Capacity of Threaded Rods
by Nikolai Sklarov and Catherina Thiele
CivilEng 2020, 1(3), 351-367; https://doi.org/10.3390/civileng1030022 - 18 Dec 2020
Cited by 1 | Viewed by 3289
Abstract
Currently, the determination of the shear capacity VRk,s0 of post installed adhesive anchors is already included in the current standardization and approval documents. Considering that EAD 330499-00-0601 allows for determining the shear resistance of a fastener only based [...] Read more.
Currently, the determination of the shear capacity VRk,s0 of post installed adhesive anchors is already included in the current standardization and approval documents. Considering that EAD 330499-00-0601 allows for determining the shear resistance of a fastener only based on the characteristic steel ultimate tensile strength fuk determined from the material tensile tests, and without considering the actual ductility of the material used, this leads to a severe underestimation of the actual steel shear resistance. In order to efficiently determine the shear strength by calculation based on material characteristics, tensile and shear tests were carried out on metallic threaded rods and rebars to show their correlation with the material properties. A new correlation between tensile and shear strength is presented, which is based on the plasticity module Epl and allows a good prognosis of the shear strength. Full article
(This article belongs to the Special Issue Connections in Concrete)
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25 pages, 9890 KiB  
Article
Evaluation of Concrete Material Properties at Early Age
by Osamah Obayes, Emad Gad, Tilak Pokharel, Jessey Lee and Kamiran Abdouka
CivilEng 2020, 1(3), 326-350; https://doi.org/10.3390/civileng1030021 - 3 Dec 2020
Cited by 16 | Viewed by 3494
Abstract
This article investigates the development of the following material properties of concrete with time: compressive strength, tensile strength, modulus of elasticity, and fracture energy. These properties were determined at seven different hydration ages (18 h, 30 h, 48 h, 72 h, 7 days, [...] Read more.
This article investigates the development of the following material properties of concrete with time: compressive strength, tensile strength, modulus of elasticity, and fracture energy. These properties were determined at seven different hydration ages (18 h, 30 h, 48 h, 72 h, 7 days, 14 days, 28 days) for four pure cement concrete mixes totaling 336 specimens tested throughout the study. Experimental data obtained were used to assess the relationship of the above properties with the concrete compressive strength and how these relationships are affected with age. Further, this study investigates prediction models available in literature and recommendations are made for models that are found suitable for application to early age concrete. Results obtained indicate that the relationship between the splitting tensile strength and concrete compressive strength can be approximated with a power function between 0.7 and 0.8, and this correlation is not affected by age. Fracture energy of the concrete and modulus of elasticity values obtained in this study correlate well with the square root of the compressive strength and it was found that this relationship holds true for all hydration ages investigated in this paper. Inverse analysis on the wedge-splitting test was conducted to determine the direct tensile strength. Values of tensile strength obtained from the inverse analysis have been validated numerically by carrying out finite element analysis on the wedge split, and anchor pull-out tests. The ratio of the tensile strength obtained from the inverse analysis to the splitting tensile strength was found to be in the range of 0.5–0.9 and 0.7 on average. Full article
(This article belongs to the Special Issue Connections in Concrete)
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16 pages, 2159 KiB  
Article
Basic Concepts of Engineering Risk Management for Fastenings and Risk Register Based on Industry Survey
by Rene Kudszus, Robert Klemencic and Panagiotis Spyridis
CivilEng 2020, 1(3), 275-290; https://doi.org/10.3390/civileng1030018 - 14 Nov 2020
Cited by 2 | Viewed by 4237
Abstract
Fastenings are becoming increasingly important in modern building practice. A wide range of products cover for the great flexibility that they provide in a large variety of applications. In order to ensure the safe and economical use of the fastenings, a combined effort [...] Read more.
Fastenings are becoming increasingly important in modern building practice. A wide range of products cover for the great flexibility that they provide in a large variety of applications. In order to ensure the safe and economical use of the fastenings, a combined effort of manufacturing firms, practicing engineers and constructors, research organizations, and public authorities has led to the establishment of interrelated design standards, application guidance, and product approvals. It is however evident that failures, in fact even small defects, of fastenings can lead to disproportionate catastrophic events. In addition to these state-of-the-art documents, which reflect the most precise knowledge possible, a management of possible residual risks and hence causes of failure is also indispensable. Due to the great range of fastening systems with different dimensioning and assembly guidelines, load-bearing behaviour and areas of application, and the overall complexity of the subject, a coherent risk management procedure against structural risks can be very helpful in this respect. This article deals with the technical and load-bearing related risks of fastening technology in construction. The objective of the paper is to introduce fundamental concepts and significant risks met in the fastenings design specification and installation. Moreover, it provides a rating of the identified risks and it transfers recommendations for risk mitigation, based on semi-structured interviews with expert professionals who are active in the field. The results are accumulated in a dedicated risk register as a standard tool of the risk management process in civil engineering, which is the first of its kind in current scientific literature. The aim is to assist future practice and research by providing a basis for risk management considerations for fastenings, which moreover reflects actual risks indicated in the outcome of an industry survey. Full article
(This article belongs to the Special Issue Connections in Concrete)
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11 pages, 3795 KiB  
Article
Statistical Evaluation of the Perpendicularity of Boreholes in Concrete for Post-Installed Fasteners
by Oliver Zeman, Michael Schwenn, Josef Schorn and Konrad Bergmeister
CivilEng 2020, 1(3), 253-263; https://doi.org/10.3390/civileng1030016 - 31 Oct 2020
Cited by 1 | Viewed by 2203
Abstract
The form and the perpendicularity of boreholes influence the ultimate behaviour of post-installed fasteners and are restricted with regard to the concrete surface to 5° in Europe and to 6° in the United States in various regulations (e.g., EAD 330232-00-0601 resp. ACI 355.2-19). [...] Read more.
The form and the perpendicularity of boreholes influence the ultimate behaviour of post-installed fasteners and are restricted with regard to the concrete surface to 5° in Europe and to 6° in the United States in various regulations (e.g., EAD 330232-00-0601 resp. ACI 355.2-19). It is assumed that the deviation of the borehole from the vertical axis has an effect on the load transfer behaviour of an anchorage. This article investigates on the perpendicularity of vertically downward drilled boreholes using different drilling tools considering hammer drilling, hollow drilling and diamond core drilling. It can be shown that the requirements of e.g., EAD 330232-00-0601 of a maximum deviation to the concrete surface of 5° can be fulfilled for approximately 95% of the determined values for different drilling methods. This is based on a considerable number of measurements (generated from drilled boreholes) in different concrete types. As a result, a detailed statistical evaluation is provided to describe the borehole perpendicularity by means of statistical methods. Full article
(This article belongs to the Special Issue Connections in Concrete)
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10 pages, 3772 KiB  
Article
Load Capacity of Shallow Embedded Anchor Channels
by Christoph Mahrenholtz and Akanshu Sharma
CivilEng 2020, 1(3), 243-252; https://doi.org/10.3390/civileng1030015 - 31 Oct 2020
Cited by 5 | Viewed by 3127
Abstract
Anchor channels are cast in concrete and allow the connection of components using channel bolts. In recent years, the design to value resulted in ever thinner concrete elements, which often cannot accommodate the required embedment depth of standard anchor channels. For this reason, [...] Read more.
Anchor channels are cast in concrete and allow the connection of components using channel bolts. In recent years, the design to value resulted in ever thinner concrete elements, which often cannot accommodate the required embedment depth of standard anchor channels. For this reason, channels may be fitted with short anchors. While existing design provisions allow for the calculation of the tension capacity also for shallow embedded anchor channels, tests are required to determine product-specific parameters for the economic shear loads design. The presented study investigated the performance of shallow embedded anchor channels tested in shear. The detailed evaluation of the test data demonstrates that testing of the minimum embedment is conservative and that the load-displacement behavior of channels with welded I-sections is comparable to that of channels with forged headed studs. In addition, a new evaluation approach is proposed. Full article
(This article belongs to the Special Issue Connections in Concrete)
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13 pages, 2812 KiB  
Article
Fire Rating of Post-Installed Anchors and Rebars
by Philipp Mahrenholtz and Akanshu Sharma
CivilEng 2020, 1(3), 216-228; https://doi.org/10.3390/civileng1030013 - 21 Oct 2020
Cited by 4 | Viewed by 3757
Abstract
Fire safety is a critical performance aspect of construction products, and post-installed anchors and rebars are no exemption in that regard. During their service life, anchors and rebars are subjected to different kinds of load actions, so they have to be qualified and [...] Read more.
Fire safety is a critical performance aspect of construction products, and post-installed anchors and rebars are no exemption in that regard. During their service life, anchors and rebars are subjected to different kinds of load actions, so they have to be qualified and designed for critical safety performance. While the qualification guidelines for static and seismic loading have matured to conclusive requirements over the past two decades, the requirements for determining the resistance to fire are just about to consolidate. This contribution strives to provide clarity on the fire rating of post-installed anchors and rebars. For this, the current status of the regulations, as well as the underlying background, is reviewed after a brief introduction. Typical examples of fire ratings in the field of post-installed anchors and rebars are given, and recent research undertaken to close the last regulative gaps is briefly presented. Full article
(This article belongs to the Special Issue Connections in Concrete)
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18 pages, 3163 KiB  
Article
Bond Modelling for the Assessment of Transmission Length in Prestressed-Concrete Members
by Nicola Fabris, Flora Faleschini and Carlo Pellegrino
CivilEng 2020, 1(2), 75-92; https://doi.org/10.3390/civileng1020006 - 30 Jun 2020
Cited by 6 | Viewed by 5874
Abstract
Transmission of the prestressing force to concrete by prestressing tendons is a topic of discussion within the fib Task Group 2.5: Bond and Material Models. Particularly, the extensive use of pretensioned prestressed-concrete (PC) requires adequate knowledge of bond development at the steel–concrete interface [...] Read more.
Transmission of the prestressing force to concrete by prestressing tendons is a topic of discussion within the fib Task Group 2.5: Bond and Material Models. Particularly, the extensive use of pretensioned prestressed-concrete (PC) requires adequate knowledge of bond development at the steel–concrete interface after prestress release. The transmission length, representing the distance from the free-end of the beam necessary to transmit the fully effective prestressing-force to the surrounding concrete, is a design parameter of paramount importance for PC members detailing. This contribution presents the analytical modelling of the transmission length based on the thick-walled cylinders (TWC) theory, considering anisotropic behaviour of the concrete. To derive the optimal friction coefficient between steel and concrete, the theoretical model has been calibrated according to an experimental database of transmission lengths collected from the literature, encompassing 130 data points from 7 different campaigns. Additionally, local behaviour has been analysed by assessing radial cracking and bond stress development along the transmission length. Full article
(This article belongs to the Special Issue Connections in Concrete)
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Review

Jump to: Research

15 pages, 1863 KiB  
Review
Review of Testing and Qualification of Post-Installed Anchors under Seismic Actions for Structural Applications
by Erik Johannes Stehle and Akanshu Sharma
CivilEng 2021, 2(2), 406-420; https://doi.org/10.3390/civileng2020023 - 24 May 2021
Cited by 1 | Viewed by 2614
Abstract
During earthquakes, buildings are subjected to loads well beyond their usual demands, resulting in high stresses in the structural components and additional inertial forces coming from the non-structural elements. When post-installed anchors are used to form the connection between non-structural or structural members [...] Read more.
During earthquakes, buildings are subjected to loads well beyond their usual demands, resulting in high stresses in the structural components and additional inertial forces coming from the non-structural elements. When post-installed anchors are used to form the connection between non-structural or structural members and the primary reinforced concrete structure, these anchors are also subjected to high seismic demands. To determine whether a post-installed anchor is suitable for such applications, it is assessed for its performance under seismic demands. In this review paper, the current European approach for testing and qualification of post-installed anchors under seismic actions is reviewed and discussed in the context of structural applications where anchors are used to form the connection between structural members that participate in the load-transfer mechanism against seismic loads. The first part of this paper provides a description of the testing procedures and the criteria against which the anchor performance is assessed. The procedures and assessment criteria are discussed regarding the suitability in the case of the above-described structural applications. In the second part, the qualification of anchors under seismic actions is discussed in the light of an upcoming performance-based design approach for anchors. In such an approach, information on the displacement and hysteretic behavior of an anchor in a broader range of the load–displacement curve is of vital importance. Therefore, additional testing approaches might be required in order to supplement the information on anchor performance provided in the current testing procedures. One such testing approach for pulsating tension load is reported. Full article
(This article belongs to the Special Issue Connections in Concrete)
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