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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.

Innovative structures can be designed with flowable concrete. A homogenous fibre distribution has to be assured by adequate mix design, whereas the fibre orientation depends on the flow and casting conditions, fibre length and rheological properties. Important work has been carried out during the past years on test methods and methods for non-destructive testing highlighting the necessity for on-site assessment of material behaviour of fibre concrete. The translation of results of small scale specimens tested in bending or in uniaxial tension is not necessarily straightforward and easy to execute considering a larger number of affecting parameters in the case of flowable concrete. This paper reviews the progress in understanding of how test results of small scale specimens relate to the structural behaviour of flowable fibre reinforced concrete. Studies reported in literature and carried out by members of fib Task Group 4.3 are considered.

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.

Research and applications of fibre-reinforced concrete (FRC) started in China during the early 1970’s, and have grown substantially over the last few decades. The first design guideline for fibre-reinforced concrete structures was developed in 1992 and subsequently updated in 2004. The design guideline focuses on steel fibre concrete, which is most commonly used in practical applications, but also has provisions for the use of synthetic fibres. In this paper, a general overview of the guideline will be provided. The design concepts for both serviceability and ultimate states are presented first. Various applications covered in the guideline, including fibre-reinforced structural or semi-structural components, pavements, bridges, hydraulic structures, shotcrete (for tunnel and repair) as well as waterproofing will then be described. By providing a concise summary of the guideline, we hope to convey an idea about the current state of fibre-reinforced concrete design in China.

The development of concrete and cement composites containing fibre reinforcement to improve tensile load-deformation behaviour has resulted in three distinct classes of materials. These are conventional fibre-reinforced concrete (FRC) with tension softening response, ultrahigh strength fibre-reinforced concrete (UFC) with increased compressive/tensile strength and high performance fibre-reinforced cement composites (HPFRCC) with strain hardening and multiple cracking characteristics. This paper introduces and compares Japan’s recommendations on the design, production and application of these fibre-reinforced concrete types with the aim of outlining distinctive and common characteristics of the different classes of cement composite materials. Examples of structural applications for HPFRCC and UFC are also described.