International Concrete Abstracts Portal

This paper first proposes a reviewing and a critical analysis of the different UHPFRC which exist, and secondly presents a new cement composite, the CEMTECmultiscale®, patented by the Laboratoire Central des Ponts et Chaussées (Paris, France). This cement composite has been tested under static bending and asymmetric fatigue bending From this experimental study, the following comments can be made : - The characteristic strength and ultimate strain in compression are respectively equal to 205 MPa, and 4 10-3. - the Young modulus is equal to 55 GPa and the Poisson coefficient is equal to 0.21. - The average modulus of rupture (MOR) is equal to 61.5 MPa; - The average strain related to the average MOR is equal to 9.2 10-3. - A critical initial static strain threshold exists. Before this threshold a specimen in CEMTECmultiscale® does not fail during a bending fatigue loading and beyond this threshold the failure fatigue cycles number linearly depends of the initial static strain. The strain threshold determined in this study is between 1.24 x 10-3 and 1.44 x 10-3. - Below a loading ratio R = 0.65, failure during bending fatigue test never appears with a specimen of CEMTECmultiscale ®.

Even though the knowledge about the load bearing behavior of Textile Reinforced Concrete (TRC) is still limited, there are already applications of TRC such as cladding panels and integrated framework systems. Up to the present, the design and dimensioning of TRC members is mainly based on extensive test series targeted to the particular application. Certainly, this approach is very goal-oriented. However, because design rules are not supported by mechanical models, high safety factors are incorporated. Within the scope of the collaborative research center “TRC: foundations for the development of a new technology” (SFB 532) at the Technical University of Aachen, Germany, the missing consistent description of the load bearing behavior of TRC is being developed. Thereby, experiments and numerical simulations at different levels, i.e., micro-, meso- and macro-levels, are performed. In this paper, the main results of the research program are presented.

This paper presents engineering use of textile reinforced concrete (TRC) for integrated formwork applications. The integrated formwork are very light compared to the normal precast elemets owing to their small thickness, typically around 10 mm. The cross-section of the integrated formwork can be chosen as dictated by the specific application, and the composite can be designed to have a high load-bearing capacity. The young concrete is protected against moisture loss by the integrated formwork that remains in place. Hence, neither demoulding nor curing of TRC integrated formork is required. The integrated formwork also possess a high quality surface appearance. In this contribution, a compilation of results from testing performed on the textile reinforced concrete integrated formwork is presented.

The composite material textile reinforced concrete (TRC) offers a number of advantages, in particular for the manufacturing of façades. The textile reinforcement and the possible thin concrete cover, enable the construction of thin-walled structural components. Filigree cladding panels made of textile reinforced concrete open up new ways for an entirely new application of the construction material concrete and give architects and engineers more freedom in the design. In this paper some basic information about the load bearing behavior of textile reinforced concrete is given and the use of textile reinforced concrete in a pilot project for the exterior claddings of the extension of the laboratory hall at the RWTH Aachen University, Germany, is described.

Thin, fiber reinforced cementitious products offer a useful balance of properties such as strength, toughness, environmental durability, moisture resistance, dimensional stability, fire resistance, aesthetics and ease of handling and installation. For more than 30 years, AR glass fibers have been at the forefront in the development of new applications of such products throughout the World. Glass Fiber Reinforced Concrete [GFRC] is a thin, cement composite based on AR glass fibers with an excellent strength to weight ratio. Extensive early laboratory work produced a test method for determining long term strength. The validity of this work has been proven by the large number of buildings clad with GFRC, as well as a vast range of other GFRC products, used over a this 30 year period. This paper explains the fundamental principles behind GFRC and gives examples of some of its uses. These applications range from high quality, architectural wall panels and decorative elements through to modular buildings down to low cost channel sections and utility components. New developments and techniques will also be discussed.