Journal articles
Author(s) | Title | Journal | Issue | Page | Category |
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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 | |||||
Nachrichten: Beton- und Stahlbetonbau 12/2011 | Beton- und Stahlbetonbau | 12/2011 | 859-864 | Nachrichten | |
Abstract• Unter gutem Stern: Bestens aufgestellt für die zukünftigen Aufgaben - Neuausrichtung der FDB von der Mitgliederversammlung befürwortet und bestätigt 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 | |||||
fib short course in Nicosia, Cyprus: Durability and retrofitting of concrete structures | Structural Concrete | 2/2011 | 129-135 | fib-news | |
Abstract• fib short course in Nicosia, Cyprus: Durability and retrofitting of concrete structures x | |||||
Concrete Model Code for Asia - Structural Concrete: Design, Materials and Construction, and Maintenance. | Bautechnik | 7/1999 | 623 | Bücher | |
Albrecht, U. | Durchstanzen bei Flachdecken - Vergleich der Bemessung und Konstruktion | Beton- und Stahlbetonbau | 3/1999 | 130-140 | Fachthemen |
AbstractDie Bemessungsansätze und die Konstruktionsregeln für den Nachweis gegen Durchstanzen von Stahlbeton-Flachdecken unterscheiden sich deutlich voneinander. Die Querkrafttragfähigkeit, die gemeinsame Tragfähigkeit von Beton und Schubbewehrung und die daran geknüpfte baulilche Durchbildung werden für vier europäische und zwei nordamerikanische Normen sowie den CEB-FIP Model Code gegenübergestellt. Am Beispiel einer Flachdecke eines Bürogebäudes mit üblichen Abmessungen wird gezeigt, welche Möglichkeiten und Grenzen die Normen im einzelnen bieten und welche baupraktischen Konsequenzen die neue DIN 1045-1 und der EC 2 haben werden. x | |||||
Allaix, Diego Lorenzo; Carbone, Vincenzo Ilario; Mancini, Giuseppe | Modelling uncertainties for the loadbearing capacity of corroded simply supported RC beams | Structural Concrete | 3/2015 | 333-341 | Technical Papers |
AbstractThe probabilistic assessment of structures damaged by corrosion calls for deterministic models of the degradation of the structural performance and probabilistic models accounting for the uncertainties in material properties, geometry and models used in the reliability analysis. This paper describes the development of a probabilistic model of the uncertainties that arise from the prediction of the loadbearing capacity of reinforced concrete structures damaged by corrosion of the reinforcement. The investigation focuses on the flexural failure of simply supported beams suffering from chloride-induced corrosion. The loss of steel cross-sectional area, the reduction in strength and ductility of the corroded bars, the loss of bond between reinforcement and concrete and the cracking of the concrete cover are taken into account in a non-linear finite element analysis. The comparison between experimental results and numerical predictions of the failure load allows the quantification of the model uncertainty according to the framework proposed by the Joint Committee on Structural Safety. A Bayesian updating methodology is proposed to account for prior knowledge and experimental results. x | |||||
Amin, Ali; Foster, Stephen J.; Muttoni, Aurelio | Derivation of the σ-w relationship for SFRC from prism bending tests | Structural Concrete | 1/2015 | 93-105 | Technical Papers |
AbstractThe material characterization of steel fibre-reinforced concrete (SFRC), which is required for its implementation in design codes, should be based on nominal properties that describe its post-cracking strength in tension. In the case of brittle and quasi-brittle materials, such as concrete, the tensile parameters are often derived indirectly. However, for materials with more ductility, such as SFRC, there is conjecture as to whether or not an indirect measure may be used to establish the stress versus crack opening displacement relationship, such as the use of a three- or four-point prism test combined with an inverse analysis. In this paper a simple and efficient inverse analysis technique is developed and shown to compare well with data obtained from direct tension tests. Furthermore, the methodology proposed by the fib Model Code for Concrete Structures 2010 has been investigated and recommendations made to improve its accuracy. x | |||||
Baji, Hassan; Ronagh, Hamid R. | A reliability-based investigation into ductility measures of RC beams designed according to fib Model Code 2010 | Structural Concrete | 4/2015 | 546-557 | Technical Papers |
AbstractA reliability-based investigation into the ductility measures for reinforced concrete (RC) beams designed according to the current fib Model Code for Concrete Structures 2010 is presented in this paper. Based on the ductility ratio (= ratio of strain in tensile rebar to yield stress of steel), a limit state to ensure adequate ductility in RC beams is proposed. Results show that the ductility ratio generally follows a right-skewed distribution, and due to variability in the material properties and model error, there is high variability in the strain ductility. This high variability in the ductility ratio leads to a high probability of non-ductile behaviour for RC beam designs based on the code. This is more pronounced for normal-strength concrete and grade S500 steel. Based on a target probability taken from the literature, a modification to the allowable neutral axis depth advised by the code is proposed. The results presented in this paper indicate that more reliability-based studies of the safety factors provided by fib Model Code 2010 are needed in order to ensure adequate ductility in RC beams. 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 | |||||
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 | |||||
Belletti, Beatrice; Damoni, Cecilia; Hendriks, Max A. N.; de Boer, Ane | Analytical and numerical evaluation of the design shear resistance of reinforced concrete slabs | Structural Concrete | 3/2014 | 317-330 | Technical Papers |
AbstractThe aim of this research is to compare the predictions of the design load-carrying capacity of slabs obtained with simplified analytical and numerical procedures which can be readily used by analysts in the current design process. The research fits into a research programme initiated by the Dutch Ministry of Infrastructure and the Environment for the re-examination of the load-carrying capacity of existing bridges and viaducts, and the beams and slabs they include, through the use of non-linear finite-element analyses. The behaviour of reinforced concrete slabs subjected to concentrated loads close to their supports is investigated in this contribution. Three tests from a series of 18 slabs with a total of 108 tests, tested at Delft University of Technology, were selected as case studies and analysed with non-linear finite-element analyses and analytical models either proposed by design codes or available in the literature. The research agrees well with the philosophy of the fib Model Code for Concrete Structures 2010, which offers different analytical and numerical calculation methods for evaluating the design shear resistance of reinforced concrete members according to different levels of approximation. For the three slabs investigated in this study, it indeed pays to use higher levels of approximation. The highest level (level IV) based on non-linear finite element analysis gives the highest design load resistance, but still well below the resistance obtained experimentally. x | |||||
Belletti, Beatrice; Pimentel, Mário; Scolari, Matteo; Walraven, Joost C. | Safety assessment of punching shear failure according to the level of approximation approach | Structural Concrete | 3/2015 | 366-380 | Technical Papers |
AbstractThe fib Model Code for Concrete Structures 2010 introduced the concept of levels of approximation (LoA) as a strategy for simplifying the procedures involved in preliminary design stages or the design of non-critical structural elements while still providing the tools for engineers to use state-of-the-art techniques in the assessment of existing structures or in the advanced stages of design for critical structural elements. In this paper, this concept is applied to the determination of the punching shear resistance of reinforced concrete slabs. A procedure is validated for the highest LoA involving non-linear finite element analysis (NLFEA) with multi-layered shell elements and the critical shear crack theory (CSCT). The safety format proposed for use in the safety verification assisted by NLFEA is based on the definition of a global resistance safety factor. A semi-probabilistic approach is followed, based on the assumption of a lognormal distribution for the resistance and on an estimate of its coefficient of variation. This approach is validated by means of a comparison with the results from a probabilistic analysis. x | |||||
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 | |||||
Blomfors, Mattias; Engen, Morten; Plos, Mario | Evaluation of safety formats for non-linear finite element analyses of statically indeterminate concrete structures subjected to different load paths | Structural Concrete | 1/2016 | 44-51 | Technical Papers |
AbstractTo increase the efficiency of new structures and perform safety evaluations of existing structures, it is necessary to model and analyse the non-linear behaviour of reinforced concrete. The applicability of the safety formats in present design codes is unclear for indeterminate structures subjected to loading in several directions. The safety formats in fib Model Code 2010 have been evaluated for a reinforced concrete frame subjected to vertical and horizontal loading and the influence of load history studied. Basic reliability methods were used together with response surfaces to assess the failure probabilities and one safety format did not meet the intended safety level. The results indicate the importance of load history and it is concluded that more research is required regarding how load history influences the safety level of complex structures. x | |||||
Buttignol, Thomaz Eduardo Teixeira; Colombo, Matteo; di Prisco, Marco | Long-term aging effects on tensile characterization of steel fibre reinforced concrete | Structural Concrete | 6/2016 | 1082-1093 | Technical Papers |
AbstractThe paper discusses the effect of aging on steel fibre reinforced concrete (SFRC) after 10 years. The aim is to observe the change in mechanical properties, especially of the residual post-cracking tensile strength, due to long-term aging. For this purpose, a comparison between the results of four-point bending tests (4PB) at the age of 1 year and 10 years was carried out and it indicates that aging affects the serviceability post-cracking residual strength, increasing fibre interfacial bond strength. Material classification is performed according to fib Model Code 2010 for 1-year old and 10-year old specimens. The objective is to estimate possible changes in the material class through the years. Three- and four-point bending test results on 10-year old specimens are described, together with a comparison between those tests. Both tests showed very similar results; slightly higher values were obtained with the three-point bending (3PB) test. The tensile constitutive law is obtained according to fib Model Code 2010 and is compared with results of direct tensile tests on cylindrical specimens and Double Edge Wedge Splitting tests on prismatic specimens. A plane section (PS) approach adopting the tensile constitutive law is applied to predict the bending behaviour in terms of nominal stress against crack mouth opening displacement and it is compared with the bending test results. x | |||||
Cairns, John | Bond and anchorage of embedded steel reinforcement in fib Model Code 2010 | Structural Concrete | 1/2015 | 45-55 | Technical Papers |
AbstractThis paper describes the changes to design provisions for embedded steel reinforcement in the fib Model Code for Concrete Structures 2010. The changes introduce new coefficients for steel grade and clear spacing between bars, and extend the range of concrete strengths covered. The way in which the contribution of hooks or anchorages is calculated has been revised and the contribution of end bearing to laps and anchorages of compression bars is recognized. The revised rules represent a move away from a distinction between laps and anchorages per se towards a distinction based on the presence or absence of transverse pressure perpendicular to the bar axis within the bond length. The benefits of staggering laps with only a proportion of bars lapped at a section are also reviewed. Finally, the potential impact of lap and anchorage performance on structural robustness is discussed, and it is concluded that this can only be achieved if bar yield precedes splitting mode bond failures. x | |||||
Cairns, John | Staggered lap joints for tension reinforcement | Structural Concrete | 1/2014 | 45-54 | Technical Papers |
AbstractStaggering lapped joints increases the complexity of detailing and steel fixing, and may require additional resources and slow construction on site. Major design codes encourage staggering lapped joints in tension by imposing a penalty on lap length depending on the proportion of bars lapped at the same section. There are, however, inconsistencies in the value of the coefficients to be applied, and little evidence is available for validation. A programme of 17 physical tests found no evidence of an increase in strength when laps were staggered, and when allowance is made for increases in transverse spacing, staggering was found to reduce lap strength. Differences in the distribution of bond stress through a lap joint and in the share of the tension force taken by continuous and lapped bars are demonstrated to be responsible for the reduction. 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 | |||||
Castel, Arnaud; Gilbert, Raymond Ian | Influence of time-dependent effects on the crack spacing in reinforced concrete beams | Structural Concrete | 3/2014 | 373-379 | Technical Papers |
AbstractThis paper aims to put into perspective the influence of long-term effects, such as concrete creep and shrinkage, on concrete cracking. Long-term experimental results obtained at the Centre for Infrastructure Engineering & Safety (CIES) are reported and compared to design estimates made using the fib Model Code for Concrete Structures 2010. The influence of factors such as stirrup spacing and concrete cover are discussed. Results show that time-dependent shrinkage-induced cracking can considerably modify the cracking patterns obtained in short-term tests. For crack control in real structures and for the development of models for inclusion in codes of practice, it is strongly recommended that account be taken of time-dependent effects. Limiting observations to those made in short-term tests may lead to erroneous conclusions that are simply not applicable for structures that are more than a few weeks old. 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 | |||||
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 | |||||
Coccia, Simona; Meda, Alberto; Rinaldi, Zila | On shear verification according to fib Model Code 2010 in FRC elements without traditional reinforcement | Structural Concrete | 4/2015 | 518-523 | Technical Papers |
AbstractFibre-reinforced concrete (FRC) without any traditional reinforcement is used particularly extensively in structures such as pavements and tunnels. The fib Model Code for Concrete Structures 2010 introduced the possibility of using FRC for structural design and it is becoming a reference document for such structures. The application of fib Model Code 2010 suggestions for flexural and axial forces, once the constitutive relationships of the material are defined, allows for safe design. However, shear verification is often a cause of discussion in the design community. The aim of this paper is to clarify this aspect and provide a procedure that can be followed in the design process. A case study is also presented. x | |||||
Colombo, Matteo; Martinelli, Paolo; di Prisco, Marco | A design approach for tunnels exposed to blast and fire | Structural Concrete | 2/2015 | 262-272 | Technical Papers |
AbstractA design procedure based on a simplified FE model for underground tunnels subjected to internal explosion and possibly preceded by fire accidents is proposed in this article. The procedure can provide a valuable tool for designers who have to check the structural safety of a tunnel for the case of an internal blast event. The tunnel geometry considered is the same adopted for the metro line in Brescia, Italy. It has an internal diameter of about 8.15 m, is about 13.7 km long and is located about 23.1 m below the surface. Six segments and a smaller key segment (6+1) make up the tunnel. The ring has an average width of about 1.5 m. The FE model is first tested under static serviceability loads. Dynamic analyses are carried out in order to reproduce the blast scenario. The aim of this work is to generate pressure-impulse (p-i) diagrams for underground tunnels for the case of internal explosion and pre-explosion fire actions. An ultimate limit state criterion based on the eccentric ultimate flexural capacity and capable of including fire-blast interaction is introduced. An innovative layered precast tunnel segment solution made of different fibre-reinforced cementitious composites is compared with a traditional solution with the lining section made of reinforced concrete. The potential applications of this new solution are also discussed in the paper. 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 |