Journal articles
Author(s) | Title | Journal | Issue | Page | Category |
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Bigaj-van Vliet, Agnieszka; Vrouwenvelder, Ton | Reliability in the performance-based concept of fib Model Code 2010 | Structural Concrete | 4/2013 | 309-319 | Technical Papers |
AbstractThe design philosophy of the new fib Model Code for Concrete Structures 2010 represents the state of the art with regard to performance-based approach to the design and assessment of concrete structures. Given the random nature of quantities determining structural behaviour, the assessment of structural performance cannot be well established by deterministic methods, instead requires a probabilistic approach. The performance-based approach is introduced in Part I of fib Model Code 2010 by applying the concept of performance requirements and reliability management during service life. Correct understanding of the reliability concept of fib Model Code 2010 is a basic prerequisite for applying its design philosophy in an appropriate manner. Therefore, the main objective of this paper is to explain some decidedly non-trivial issues related to safety and reliability management aspects. In this context, this paper indicates how this general philosophy in fib Model Code 2010 is further developed into a set of operational rules for the design and assessment of concrete structures. x | |||||
Müller, Harald S.; Anders, Isabel; Breiner, Raphael; Vogel, Michael | Concrete: treatment of types and properties in fib Model Code 2010 | Structural Concrete | 4/2013 | 320-334 | Technical Papers |
AbstractSection 5.1 “Concrete” of the fib Model Code for Concrete Structures 2010 contains basic definitions and well-established constitutive relations for structural concrete. However, it also presents various new approaches and updated models compared with the earlier CEB-FIP Model Code 1990. This is particularly true for the strength, stress and strain characteristics of structural concrete, for creep and shrinkage and for sophisticated durability-related processes. The validity of the models has been extended to several types of concrete such as high strength concrete, self-compacting concrete and lightweight aggregate concrete. The durability-related models are either suitable for facilitating a full probabilistic service life design or for applying simpler code-type approaches. x | |||||
Triantafillou, Thanasis; Matthys, Stijn | Fibre-reinforced polymer reinforcement enters fib Model Code 2010 | Structural Concrete | 4/2013 | 335-341 | Technical Papers |
AbstractMost applications of fibre-reinforced polymers (FRP) deal with externally bonded reinforcement as a means of repairing and strengthening reinforced concrete (RC) structures or retrofitting RC structures in seismic regions. As internal reinforcement, FRP rebars or (more rarely) prestressing elements are used in special projects, combining material strength and durability characteristics. Over the last years, several national and international design guidelines have become available specifically for the design and application of FRP-strengthened or FRP-reinforced concrete structures. These efforts clearly demonstrate the interest in FRP as a novel reinforcing material for concrete construction. Hence, the time had come to introduce FRP reinforcement into the new fib Model Code for Concrete Structures 2010 as well. The main contributions to the fib Model Code 2010 relate to sections 5.5 “Non-metallic reinforcement” and 6.2 “Bond of non-metallic reinforcement”. The material presented in those two sections is further elaborated in this article. x | |||||
di Prisco, Marco; Colombo, Matteo; Dozio, Daniele | Fibre-reinforced concrete in fib Model Code 2010: principles, models and test validation | Structural Concrete | 4/2013 | 342-361 | Technical Papers |
AbstractIn the fib Model Code for Concrete Structures 2010, fibre-reinforced concrete (FRC) is recognized as a new material for structures. This introduction will favour forthcoming structural applications because the need of adopting new design concepts and the lack of international building codes have significantly limited its use up to now. In the code, considerable effort has been devoted to introducing a material classification to standardize performance-based production and stimulate an open market for every kind of fibre, favouring the rise of a new technological player: the composite producer. x | |||||
Matthews, Stuart; Bigaj-van Vliet, Agnieszka | Conservation of concrete structures according to fib Model Code 2010 | Structural Concrete | 4/2013 | 362-377 | Technical Papers |
AbstractConservation of concrete structures forms an essential part of the fib Model Code for Concrete Structures 2010 (fib Model Code 2010). In particular, Chapter 9 of fib Model Code 2010 addresses issues concerning conservation strategies and tactics, conservation management, condition surveys, condition assessment, condition evaluation and decision-making, making interventions and the recording of information for through-life management. x | |||||
Silva, Ricardo; Faria, Duarte M. Viúla; Ramos, A. Pinho; Inácio, Micael | A physical approach for considering how anchorage head size influences the punching capacity of slabs strengthened with vertical steel bolts | Structural Concrete | 4/2013 | 389-400 | Technical Papers |
AbstractThe introduction of new vertical steel bolts is an easy, practical and common solution for retrofitting and strengthening slabs for punching. Although a common option where punching strengthening is concerned, few studies exist regarding how the bolt's anchorage dimensions and its embedment in the concrete slab affect the strengthening efficiency. This work presents an analytical approach that is able to predict the punching capacity of slabs strengthened with post-installed vertical steel bolts, taking into account the anchorage dimensions and positioning plus the material properties. This approach results from the combination of two physical models: one provided in the fib Model Code for Concrete Structures 2010 regarding the punching capacity estimation, and another that allows the deformation (crushing) of the concrete beneath the head of the anchorage to be taken into account. The predicted values are compared with experimental results, showing that the analytical approach is able to simulate correctly the anchorage behaviour and its influence regarding a slab's loadbearing capacity. A parametrical analysis is carried out in order to study the importance of different factors such as concrete compressive strength, longitudinal reinforcement ratio and steel bolt length, always accompanied by the effect of anchorage head size and embedment. x | |||||
Sagaseta, Juan | The influence of aggregate fracture on the shear strength of reinforced concrete beams: an experimental and analytical research project | Structural Concrete | 4/2013 | 401-414 | Technical Papers |
AbstractHigh-performance concretes such as high-strength concrete (HSC) or lightweight aggregate concrete (LWAC) are generally used to reduce member sizes and self-weight, and to optimize the construction of reinforced concrete structures. The bond between the aggregate particles and the cement paste can be strong enough in HSC and LWAC to cause the aggregate to fracture at cracks, which in turn reduces the shear stress that can be transferred across cracks by means of aggregate interlock. Relatively smooth cracks can also develop in self-compacting concrete due to the low coarse aggregate content. The contribution of aggregate interlock to the shear strength of RC beams is uncertain and depends on parameters such as the amount of shear reinforcement or the contribution of arching action for loads applied close to the support. Existing tests on slender RC beams without shear reinforcement have shown that shear strength is reduced by aggregate fracture. However, there is a lack of similar test data for members with stirrups and for members with varying shear span/effective depth ratios. This paper reviews the findings and contributions in this area from the experimental and analytical research of the author's PhD thesis, which was awarded the fib Achievement Award for Young Engineers in 2011. x | |||||
fib-news: Structural Concrete 4/2013 | Structural Concrete | 4/2013 | 424-433 | fib-news | |
AbstractResults of the 2014 fib Awards for Outstanding Concrete Structures competition x | |||||
Sigrist, Viktor; Bentz, Evan; Ruiz, Miguel Fernández; Foster, Stephen; Muttoni, Aurelio | Background to the fib Model Code 2010 shear provisions - part I: beams and slabs | Structural Concrete | 3/2013 | 195-203 | Technical Papers |
AbstractThis paper examines the evidence for the one-way shear model developed for the fib Model Code for Concrete Structures 2010 and provides examples of its application. For the design and analysis for shear, for members with and without shear reinforcement, the fib Model Code 2010 procedures have been developed from physical-mechanical models that are based on observed behaviour at the meso-scale level; they represent a significant advance over previous standardized empirical methods. In addition, an approach referred to as “level of approximation” (LoA) is incorporated where advanced models are simplified in a consistent and conservative way such that the designer can select the effort needed to justify their design. To illustrate the practical use of the models and the LoA approach, two examples are presented. The first is a deck slab of a cut-and-cover tunnel where design and possible refinements are discussed for a given configuration. The second is a prestressed concrete bridge girder, which is considered for the cases of design and for the analysis of an existing structure. x | |||||
Muttoni, Aurelio; Ruiz, Miguel Fernández; Bentz, Evan; Foster, Stephen; Sigrist, Viktor | Background to fib Model Code 2010 shear provisions - part II: punching shear | Structural Concrete | 3/2013 | 204-214 | Technical Papers |
AbstractThis paper outlines the theoretical background to the punching shear provisions implemented in the fib Model Code for Concrete Structures 2010 and presents a practical example of their application. The aim is to explain the mechanical model that forms the basis for the punching design equations, to justify the relevance of the provisions and to show their suitability for the design and assessment of structures. x | |||||
Fardis, Michael N. | Performance- and displacement-based seismic design and assessment of concrete structures in fib Model Code 2010 | Structural Concrete | 3/2013 | 215-229 | Technical Papers |
AbstractThe scope of fib Model Code for Concrete Structures 2010 includes the fully fledged performance- and displacement-based seismic design of new structures and assessment of existing ones. This part of fib Model Code 2010 covers buildings, bridges or similar concrete structures and aims to provide well-defined performance levels for specific seismic hazard levels. Detailing of members for ductility is not based on opaque prescriptions, as in current codes, but on transparent, explicit verification of inelastic deformation demands against capacity limits. The reference analysis method is non-linear dynamic, but under certain conditions inelastic deformation demands may be estimated from linear analysis and the 5%-damped elastic response spectrum; in that case force demands on force-controlled, brittle failure modes are estimated from the plastic mechanism through equilibrium. In order to predict the seismic deformation demands with some confidence, the analysis should use realistic values for the member secant stiffness up to the yield point. The paper explains the background to the expressions given for this property in fib Model Code 2010 as well as of those for the deformation limits used when verifying seismic deformation demands. The modifications to the shear resistance approach of fib Model Code 2010, which takes cyclic loading into account, are also explained and justified. x | |||||
Randl, Norbert | Design recommendations for interface shear transfer in fib Model Code 2010 | Structural Concrete | 3/2013 | 230-241 | Technical Papers |
AbstractInterface shear transfer between differently aged concretes is a topic that crops up frequently and in different situations in structural design. In the fib Model Code for Concrete Structures 2010 the fundamental basics of concrete-to-concrete load transfer are given in section 6.3 and the corresponding design rules in 7.3.3.6. The different potential mechanisms contributing to the shear resistance along the interface, i.e. adhesive bond, aggregate interlock, friction and dowel action, are thus combined and their relationship taken into account by interaction factors. This article summarizes the most important results from past and ongoing studies and presents the background to the theory forming the design basis of fib Model Code 2010, the “extended shear friction theory” (ESF). x | |||||
Belletti, Beatrice; Damoni, Cecilia; den Uijl, Joop A.; Hendriks, Max A. N.; Walraven, Joost C. | Shear resistance evaluation of prestressed concrete bridge beams: fib Model Code 2010 guidelines for level IV approximations | Structural Concrete | 3/2013 | 242-249 | Technical Papers |
AbstractThe design shear resistance of an existing structure can be evaluated with analytical design procedures and numerical procedures provided by non-linear finite element analyses. The new fib Model Code 2010 proposes different calculation methods that fall into four different levels of approximation. As the level of approximation rises, so the complexity and the accuracy of the calculated shear resistance increases. Non-linear finite element analyses belong to the highest level of approximation, but although they are more and more becoming a customary tool in the daily design process, building codes do not provide guidance on how to perform these analyses. x | |||||
Corres-Peiretti, Hugo | Sound engineering through conceptual design according to the fib Model Code 2010 | Structural Concrete | 2/2013 | 89-98 | Technical Papers |
AbstractConceptual design is the approach that creates an idea in order to find a solution to a new proposal for a structure or solve a detail in a specific structure. It is a personal approach that is learned over time and with experience. It is not normally dealt with at university, but is vitally important for producing sound structures. x | |||||
Balázs, György L.; Bisch, Philippe; Borosnyói, Adorján; Burdet, Olivier; Burns, Clare; Ceroni, Francesca; Cervenka, Vladimir; Chiorino, Mario A.; Debernardi, Piergiorgio; Eckfeldt, Lars; El-Badry, Mamdouh; Fehling, Ekkehard; Foster, Stephen J.; Ghali, Amin; Gribniak, Viktor; Guiglia, Matteo; Kaklauskas, Gintaris; Lark, Robert J.; Lenkei, Peter; Lorrain, Michel; MarÃ, Antonio; Ozbolt, Josko; Pecce, Marisa; Pérez Caldentey, Alejandro; Taliano, Maurizio; Tkalcic, Damir; Torrenti, Jean Michel; Torres, Lluis; Toutlemonde, François; Ueda, Tamon; Vitek, Jan L.; VráblÃk, Luká | Design for SLS according to fib Model Code 2010 | Structural Concrete | 2/2013 | 99-123 | Technical Papers |
AbstractThis paper provides an overview of serviceability specifications given by the fib Model Code for Concrete Structures 2010 (fib MC2010 [1]). First, the reasons behind crack control and deflection control are discussed, then specific design rules are provided. Simple rules as well as detailed models are also presented. Numerical examples are provided in order to assist in the application of the design recommendations for crack control and deflection control (reinforced and prestressed concrete elements). x | |||||
Clément, Thibault; Ramos, António Pinho; Fernández Ruiz, Miguel; Muttoni, Aurelio | Design for punching of prestressed concrete slabs | Structural Concrete | 2/2013 | 157-167 | Technical Papers |
AbstractPrestressing in flat slabs helps to control deformations and cracking under service loads and allows the required slab thickness to be reduced, thus leading to more slender structures and an economic solution for long spans. However, as a consequence of the limited thickness of these members, punching typically governs at the ultimate limit state. Studies of the punching shear strength have shown that the presence of prestressing in flat slabs has a number of potential beneficial effects, namely the vertical component (force) carried by inclined tendons, the in-plane compression stresses and the bending moments developed near the supported region. However, the approach provided by codes of practice for punching design in the presence of prestressing may differ significantly. Some codes neglect the influence of the bending moments introduced as a result of prestressing and the sections at which the deviation forces of the tendons are considered may be located at different distances from the edge of the supported region. The influence of prestressing on the punching shear strength of members without shear reinforcement is investigated in this paper by using the fundamentals of the critical shear crack theory. Using that as a basis, and also taking into account 65 tests available in the scientific literature, the suitability and accuracy of a number of design codes, e.g. Model Code 2010, Eurocode 2 and ACI 318-11, are investigated and compared. x | |||||
Walraven, Joost; Balázs, György L. | fib Model Code for Concrete Structures 2010: a landmark in an ongoing development | Structural Concrete | 1/2013 | 1-2 | Editorial |
Walraven, Joost | fib Model Code for Concrete Structures 2010: mastering challenges and encountering new ones | Structural Concrete | 1/2013 | 3-9 | Technical Papers |
AbstractThe Model Code for Concrete Structures 2010 is a recommendation for the design of structural concrete, written with the intention of giving guidance for future codes. As such, the results of the newest research and development work are used to generate recommendations for structural concrete at the level of the latest state of the art. While carrying out this exercise, areas are inevitably found where information is insufficient, thus inviting further study. This paper begins with a brief introduction to the new expertise and ideas implemented in fib Model Code 2010, followed by a treatment of areas where knowledge appeared to be insufficient or even lacking and where further research might be useful. x | |||||
Helland, Steinar | Design for service life: implementation of fib Model Code 2010 rules in the operational code ISO 16204 | Structural Concrete | 1/2013 | 10-18 | Technical Papers |
AbstractCEB/FIP Model Code 1990 (MC-1990) did represent the technology and focus some 20 years ago. However, it soon became evident that the document had some notable lacunas. In 1995 the general assemblies of the two organizations endorsed CEB/FIP bulletin No. 228, extensions to MC 1990 for high-strength concrete, and in 2000 a similar extension to MC 1990 for lightweight aggregate concrete as bulletin No. 4. x | |||||
Cervenka, Vladimir | Reliability-based non-linear analysis according to fib Model Code 2010 | Structural Concrete | 1/2013 | 19-28 | Technical Papers |
AbstractThe fib Model Code 2010 for Concrete Structures introduces numerical simulation as a new tool for designing reinforced concrete structures. The model of resistance based on non-linear analysis requires adequate model validation and a global safety format for verifying designs. The numerical simulations combined with random sampling offer the chance of an advanced safety assessment. Approximate methods of global safety assessment are discussed and compared in a case study. An example of a bridge design supported by non-linear analysis is shown. x | |||||
Pérez Caldentey, Alejandro; Corres Peiretti, Hugo; Peset Iribarren, Joan; Giraldo Soto, Alejandro | Cracking of RC members revisited: influence of cover, &phgr;/&rgr;s, ef and stirrup spacing - an experimental and theoretical study | Structural Concrete | 1/2013 | 69-78 | Article |
AbstractThis article describes an experimental programme aimed at studying the effect of cover, ratio between diameter and effective reinforcement ratio (&phgr;/&rgr;s, ef) and the influence of stirrup spacing on the cracking behaviour of reinforced concrete elements. The experimental programme was conceived in order to contribute to the debate - fuelled by the publication in recent years of Eurocode 2 EN1992-1-1 and the revision of the Model Code under way when the tests were carried out (and now published as a finalized document) - regarding the influence of these parameters on cracking. Important theoretical aspects are discussed, including where the crack width is estimated by current code formulations and what relevance this may have on the correlation between crack opening and durability of RC structures, especially with regard to structures with large covers. The effect of stirrup spacing, a variable absent from current codes, is also discussed. x | |||||
Caratelli, Angelo; Meda, Alberto; Rinaldi, Zila | Design according to MC2010 of a fibre-reinforced concrete tunnel in Monte Lirio, Panama | Structural Concrete | 3/2012 | 166-173 | Articles |
AbstractThis paper discusses the possibility of using precast tunnel segments in fibre-reinforced concrete without traditional reinforcement. The case study of a hydraulic tunnel in Monte Lirio, Panama, excavated with a tunnel boring machine (TBM) by SELI S.p.A., has been analysed. x | |||||
Lohaus, Ludger; Oneschkow, Nadja; Wefer, Maik | Design model for the fatigue behaviour of normal-strength, high-strength and ultra-high-strength concrete | Structural Concrete | 3/2012 | 182-192 | Articles |
AbstractFatigue design according to CEB-FIP Model Code 90 is limited to concrete grades up to C80. In addition, the design rules include a strength-dependent reduction in the fatigue reference strength, which leads to uneconomical design of high-strength concrete. Considering comprehensive knowledge now available concerning the fatigue behaviour of normal-strength and high-strength concretes, the amount of this reduction can no longer be justified. A new design model for compressive fatigue loading and its derivation is presented in this article. A comparison between the new design model and the current standard ones reveals that the new design model ensures safe and economical design of normal-strength, high-strength and ultra-high-strength concrete. This new design model is included in the new fib Model Code 2010. x | |||||
Muttoni, Aurelio; Ruiz, Miguel Fernández | The levels-of-approximation approach in MC 2010: application to punching shear provisions | Structural Concrete | 1/2012 | 32-41 | Articles |
AbstractIn order to address how new knowledge influences design expressions, design codes have in most cases become significantly more complex over the last decades. However, this tendency is leading to codes that are too complicated for preliminary design but still not sufficiently accurate for assessing existing structures (where even more realistic models of behaviour are sometimes required). An alternative code strategy is that proposed by codes based on a levels-of-approximation (LoA) approach. This approach is based on the use of theories based on physical parameters where the hypotheses for their application can be refined as the accuracy required increases. The approach proposes adopting safe hypotheses during the first stages of design, leading to relatively quick and simple analyses. In cases where such a degree of accuracy is not sufficient (e.g. design of complex structures, assessment of existing structures, significant potential economic savings), the hypotheses can be refined in a number of steps, leading to better estimates of the behaviour and strength of members. This approach, recently adopted in the first complete draft of Model Code 2010 for a number of design issues, is discussed within this paper with reference to punching shear provisions. x | |||||
fib-news: Structural Concrete 04/2011 | Structural Concrete | 4/2011 | 281-289 | fib-news | |
Abstract• fib General Assembly approves the Model Code 2010 x |