Publication

ARCHE D06 - Recommendations for the tailoring of UHPFRC recipes for rehabilitation

Emmanuel Denarié
2009
Reports

Abstract

The extremely low permeability of Ultra High Performance Fibre Reinforced Concretes (UHPFRC) associated to their outstanding mechanical properties make them especially suitable to locally "harden" reinforced concrete structures in critical zones subjected to an aggressive environment and to significant mechanical stresses. UHPFRC provide a unique and robust solution to simplify the construction process, dramatically reduce the duration of sites, and save money with long term durability. Rehabilitations, especially with cast on site UHPFRC are among the most demanding applications for those materials and require a significant strain hardening response under tension. Achievement of tensile strain hardening, extremely low permeability and self-compacting character is indeed a challenge that few current UHPFRC recipes can satisfy. Cement-superplasticisers compatibility issues severely restrict the range of possibilities to develop new UHPFRC recipes based on locally available components with the required properties for cast in situ applications. An original concept of Ultra High Performance matrix has been developed that makes the application of UHPFRC technology feasible with a wide range of cements and superplasticisers, with outstanding mechanical and protective performance, without significant loss of workability. This concept is an extension to UHPFRC materials of the concepts of cements blended with Limestone fillers, already applied successfully to a wide range of normal or high performance concretes. In a further step, the rheology of those mixes has been adapted to enable them to support challenging 5 % slopes of the substrates at fresh state. The development of this new technology and its portability in various countries opens very promising perspectives for the dissemination of this concept not only for rehabilitation but also for various applications of UHPFRC, prefabricated or cast-in-situ. This document presents both a general methodology for the tailoring of UHPFRC recipes (fibrous mix and matrix) and its application to Slovene and Polish components.

Official source

https://infoscience.epfl.ch/entities/publication/3e907ec9-b687-461f-ad80-e0a27222096e

Emmanuel Denarié
2009
Reports

Abstract

Official source

https://infoscience.epfl.ch/entities/publication/3e907ec9-b687-461f-ad80-e0a27222096e

Related concepts (31)

Stress–strain curve

In engineering and materials science, a stress–strain curve for a material gives the relationship between stress and strain. It is obtained by gradually applying load to a test coupon and measuring the deformation, from which the stress and strain can be determined (see tensile testing). These curves reveal many of the properties of a material, such as the Young's modulus, the yield strength and the ultimate tensile strength. Generally speaking, curves representing the relationship between stress and strain in any form of deformation can be regarded as stress–strain curves.

Types of concrete

Concrete is produced in a variety of compositions, finishes and performance characteristics to meet a wide range of needs. Modern concrete mix designs can be complex. The choice of a concrete mix depends on the need of the project both in terms of strength and appearance and in relation to local legislation and building codes. The design begins by determining the requirements of the concrete. These requirements take into consideration the weather conditions that the concrete will be exposed to in service, and the required design strength.

Yield (engineering)

In materials science and engineering, the yield point is the point on a stress-strain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Below the yield point, a material will deform elastically and will return to its original shape when the applied stress is removed. Once the yield point is passed, some fraction of the deformation will be permanent and non-reversible and is known as plastic deformation.

Related publications (29)

Influence of model uncertainty and long term deformations in action effects calculation in reinforced concrete structures

Xhemsi Malja

Most codes of practice adopt a semi probabilistic design approach for the dimensioning and assessment of structures. Accordingly, structural safety is ensured by performing limit state verifications using design values determined with adequately calibrated ...

EPFL2024

Decarbonization potential of steel fibre-reinforced limestone calcined clay cement concrete one-way slabs

Hisham Tarek Mohamed Hafez

This study deals with a comparison of the environmental performance of one-way slabs utilizing steel fibrereinforced limestone calcined clay cement (LC3) concrete with the control case of Ordinary Portland cement concrete. The experimental program constitu ...

Elsevier Sci Ltd2024

Experimental investigation of dowel action in reinforcing bars using refined measurements

Aurelio Muttoni, Marko Pejatovic

In typical reinforced concrete design, reinforcement is designed to carry axial forces, but it can also resist transversal forces by dowel action. This is usually neglected for simplicity's sake in the design phase, but it can be accounted for either expli ...

Ernst & Sohn2024