This paper enumerates the reasons that motivate the use of finite elements simulations for the analysis of cracking behaviour in the design of SFRC structures. These reasons are mainly due to the irrelevancy of current design recommendations, which do not adequately take into account certain technical problems, such as the evaluation of the crack openings in SFRC structures under serviceability loads, the analysis of the non-linear behaviour of concrete structures under shear and punching, and the analysis of the non-linear behaviour of indeterminate concrete structures.

This paper also proposes the main criteria that a relevant numerical model of SFRC cracking needs to respect in order to simulate cracking. Finally, an example of such a relevant model is presented along with its validation in the context of the shear behaviour of a large SFRC beam.

In the fib Model Code 2010, fibre-reinforced concrete (FRC) is finally recognized as a cement composite material for construction: this step favours significant structural applications based on new concept requirements. In the Model Code, a strong effort has been devoted to introducing a material classification in order to standardize a performance-based production and stimulate an open market for every kind of fibre, favouring the rising of a new technological actor: the composite producer. From standard classification, the simple constitutive models introduced allow designers to identify effective design constitutive laws, trying to take into account the fibres contribution in term of performance and suitably orienting its structural use. An FRC application concerning tunnelling is discussed here, focusing on the design requirements and structural advantages offered by fibres addition and on further research needs. In this application a useful combination of strain softening and strain hardening materials allowed by the unified Model Code approach can offer designers interesting opportunities and new structural challenges.

The concrete precast industry often has to cope with the difficulties concerning the production of structural elements with complex or atypical shapes. This is the case of flat concrete slabs, whose thin geometry involves difficulties in the placement of reinforcement, resulting in a large cost and time consumption during the construction process. This paper presents the results of research project which aims to optimize the geometry and the reinforcement of floor slabs for precast electrical equipment shelters. The results obtained by testing five simply supported full scale steel-fibre-reinforced self-compacting concrete thin slabs, subjected to point loads and continuously supported over the four edges, are reported and discussed. Non-linear finite element simulations are also presented to corroborate the experimental results and propose design solutions for reinforcement optimization.

Fibre-reinforced self-compacting concrete (FR-SCC) combines the benefits of highly flowable concrete in the fresh state with enhanced performance in the hardened state in terms of crack control and fracture toughness provided by the dispersed fibre reinforcement. A “holistic” approach can be conceived to the design of structure made with highly flowable/selfconsolidating FRC, which encompasses the influence of fresh-state performance and casting process on fibre dispersion and orientation, and the related outcomes in terms of hardened state properties. In this framework, this paper, after a review of the current state of the art on the aforementioned topics based on the research performed by the author in the last decade, the research needs will be discussed which have to be urgently tackled in order to address the use of this kind of advanced cement based materials for high-end structural applications.

In recent years, because of developments in materials technology, by the understanding of fundamental relationships as well as due to experimentally and numerically driven modelling and design, the use of steel-fibre-reinforced concrete (SFRC) is steadily increasing. One major issue which needs to be taken particularly into account for most SFRC applications is the evidence of their structural safety under fire exposure. This paper gives an overview of nationally and internationally available normative and pre-normative requirements and codetype regulations to model and design both the material and structural behaviour of fireexposed SFRC. The paper will also illustrate that the fire behaviour of SFRC needs to be mandatorily considered both from a technical and legal perspective. Since an implied fire design approach is still pending, experimental verifications are still recommended on a material level but primarily on a structural level in order to provide technically and economically reasonable solutions which do not restrict innovative stages due to conservative assumptions.