Fibre‐reinforced concrete in fib Model Code 2010: principles, models and test validation
TL;DR: In the fib Model Code for Concrete Structures 2010, fiber-reinforced concrete (FRC) is recognized as a new material for structures as discussed by the authors, and the most important constitutive law introduced is the stress-crack opening response in uniaxial tension.
Abstract: In 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.
Starting from standard classification, the simple constitutive models introduced allow the designer to identify effective constitutive laws for design, trying to take into account the major contribution in terms of performance and providing good orientation for structural uses. Basic new concepts such as structural characteristic length and new factors related to fibre distribution and structural redistribution benefits are taken into account. A few examples of structural design starting from the constitutive laws identified are briefly shown.
FRC can be regarded as a special concrete characterized by a certain toughness after cracking. For this reason, the most important constitutive law introduced is the stress-crack opening response in uniaxial tension. A wide discussion of the constitutive models introduced to describe this behaviour, which controls all the main contributions of fibres for a prevailing mode I crack propagation, is proposed. The validity of the models is discussed with reference to ordinary cross-sections as well as thin-walled elements by adopting plane section or finite element models.
Citations
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TL;DR: In this paper, the authors propose to use 3D printed concrete structures that allow for robust and ductile printed objects to be used in building concrete structures. But, they do not specify how to construct them.
Abstract: With the number of 3D printed concrete structures rapidly increasing, the demand for concepts that allow for robust and ductile printed objects becomes increasingly pressing. An obvious solution st...
114 citations
Cites background from "Fibre‐reinforced concrete in fib Mo..."
...These approaches are elaborated by Di Prisco, Colombo, and Dozio (2013) and depend on stress distributions, structural characteristic length (lcs, essentially identical to the crack band width wc), and Young’s modulus – all of which have to be assumed and are functions of the strain....
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TL;DR: In this article, a simple and efficient inverse analysis technique is developed and shown to compare well with data obtained from direct tension tests, and the methodology proposed by the fib Model Code for Concrete Structures 2010 has been investigated and recommendations made to improve its accuracy.
Abstract: The 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 postcracking 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 fourpoint 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.
88 citations
Cites methods or result from "Fibre‐reinforced concrete in fib Mo..."
...However, although this methodology has been incorporated in the fib Model Code for Concrete Structures 2010 [8–10], the test data available at the time for full validation was somewhat limited [11]....
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...[11] for comparison with fib Model Code 2010 [10] model) and Deluce [35]....
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...This is similar to the value determined in [8, 11] for the case where α = 0....
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...Similarly, CMOD4 is adopted, rather than CMOD3, to maximize the distance between the first and second key points and increase the reliability of the ap- 0 0.5 1 1.5 COD, w (mm) 0 1 2 3 4 5 6 T en si le S tr es s ( M Pa ) di Prisco et al. (2013) - M3-F2-0....
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Journal Article•
TL;DR: In this article, hydraulic applications of fiber reinforced concrete in spillway channels, tunnels through dams and their abutments, and stilling basins; refractory applications in airfield pavements; and building applications in curtainwall panels are discussed.
Abstract: Hydraulic applications of fiber reinforced concrete in spillway channels, tunnels through dams and their abutments, and stilling basins; refractory applications in airfield pavements; and building applications of fiber concrete in curtainwall panels are discussed.
79 citations
TL;DR: In this article, a probabilistic model considering the previous research with stereographical assumptions has been performed allowing the use of fibres that can bend, and the model coincides with the most accepted values and represents with accuracy the existence of boundaries.
Abstract: The orientation and distribution of the fibres is decisive in the mechanical behaviour of fibre-reinforced concrete. Several classical models have extensively been used for the case of rigid steel fibres. The increasing interest in structural synthetic fibres that can bend demanded new considerations in this matter. A probabilistic model considering the previous research with stereographical assumptions has been performed allowing the use of fibres that can bend. This paper also provides significant tools for design engineering in order to predict and confirm the number of fibres crossing a vertical surface using fibre reinforced concrete with steel and polyolefin fibres. Additionally, the proposed model coincides with the most accepted values and represents with accuracy the existence of boundaries.
75 citations
TL;DR: In this paper, the performance of steel fiber-reinforced concrete made with recycled concrete aggregates and desert dune sand was evaluated and compared with those of a mixture made with natural coarse aggregates (NA).
66 citations
References
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01 Jan 2008
TL;DR: In this article, fracture mechanics is introduced into finite element analysis by means of a model where stresses are assumed to act across a crack as long as it is narrowly opened, which may be regarded as a way of expressing the energy adsorption in the energy balance approach.
Abstract: A method is presented in which fracture mechanics is introduced into finite element analysis by means of a model where stresses are assumed to act across a crack as long as it is narrowly opened. This assumption may be regarded as a way of expressing the energy adsorption GC in the energy balance approach, but it is also in agreement with results of tension tests. As a demonstration the method has been applied to the bending of an unreinforced beam, which has led to an explanation of the difference between bending strength and tensile strength, and of the variation in bending strength with beam depth.
5,564 citations
TL;DR: In this article, fracture mechanics is introduced into finite element analysis by means of a model where stresses are assumed to act across a crack as long as it is narrowly opened, which may be regarded as a way of expressing the energy adsorption in the energy balance approach.
5,505 citations
TL;DR: In this article, the main concepts behind the structural rules for Fibre Reinforced Concrete structural design are briefly explained, and a New fib Model Code that aims to update the previous CEB-FIP Model Code 90, published in 1993, is presented.
Abstract: Although the use of Fibre Reinforced Concrete (FRC) for structural applications is continuously increasing, it is still limited with respect to its potentials, mainly due to the lack of International Building Codes for FRC structural elements. Within fib (Federation Internationale du Beton), the Special Activity Group 5 is preparing a New fib Model Code that aims to update the previous CEB-FIP Model Code 90, published in 1993, that can be considered as the reference document for Eurocode 2. The New Model Code includes several innovations and addresses among other topics, new materials for structural design. In this respect, FRC will be introduced. The Technical Groups fib TG 8.3 “Fibre reinforced concrete” and fib TG 8.6 “Ultra high performance FRC” are preparing some sections of the New Model Code, including regular and high performance FRC. This paper aims to briefly explain the main concepts behind the structural rules for FRC structural design.
433 citations
Book•
01 Jan 2008
380 citations
01 Jun 1964
348 citations