The use of Ultra High Performance Fibre Reinforced cement-based Composites in rehabilitation projects: a review

Abstract

Ultra High Performance Fibre Reinforced cement-based Composites (UHPFRC) form a novel material developed over the last two decades. A set of special traits, such as durability, outstanding material properties, and ease of application, render UHPFRC particularly attractive for the improvement (rehabilitation, strengthening) of concrete structures. Laboratory tests indicate a compressive strength, which ranges from 150 to 200 MPa, while tensile strength lies in the range of 7-15 MPa. The fibres play an important role in defining the range of these properties depending on the content (3-6%), orientation, length and composition. As a consequence, UHPFRC delivers a workable material whose mechanical properties may be properly adjusted according to the desired application scheme. As indicated via laboratory testing and in-situ experience, the durability of the structure may be extended not only due to the properties of UHPFRC but also due to the additional protection it offers to the reinforcement. This paper provides an overview on existing findings of UHPFRC implementations, focusing in the domain of improvement of structures. Within this context, UHPFRC may be applied on top of existing bridge decks [1],with or without steel rebars, ensuring full bond conditions via mere surface preparation prior to casting. In exploiting the attributes of UHPFRC within a rehabilitation context, further applications are being explored, such as strengthening of orthotropic steel decks in order to prevent fatigue issues [2]. Nonetheless, it should also be acknowledged that certain aspects need to be improved such as the development of a multi scale analysis framework, able to provide a detailed computational method without detriment to time efficiency. The introduction of monitoring technologies in structures with UHPFRC would unquestionably provide valuable insight into its long-term performance and help validate this scheme for the next generation of rehabilitation interventions.

Appraisal of Indigenous Materials for Use in the Production of Ultra High Performance Fibre Reinforced Concrete

“…Hence, it is crucial to develop novel concepts for the strengthening of concrete structures. Martín-Sanz, Chatzi, and Brühwiler (2016) reported that promising is the applicability of UHPFRC at increased slopes, delivering satisfactory results which permits rehabilitation of surfaces that are not easily accessible by other means. Lampropoulos, Paschalis, Tsioulou, and Dritsos (2016) observed superior performance for beams strengthened with UHPFRC three side jackets, and the shrinkage strain was 30% reduced in case of UHPFRC with 3% steel fibres, compared to the respective measurements of plain UHPFRC.…”

New Trends for Reinforced Concrete Structures: Some Results of Exploratory Studies

“…Most of these studies were focused on the material properties, and only few addressed the behaviour of structural UHPC members. In this latter group of studies is included the work by Bruwhiler et al, developed at EPFL, which uses UHPC to improve the performance of both existing and new concrete structures [42,43].…”

Validación experimental de un modelo de Inteligencia Artificial para la capacidad de absorción de energía del UHPFRC

“…El comportamiento mecánico bajo pruebas de tracción directa del UHPFRC puede clasificarse como ''ablandamiento por deformación'' o ''endurecimiento por deformación'' [24,25]. El efecto de las fibras cosiendo la fisura generada afecta significativamente al rendimiento en el dominio de endurecimiento y ablandamiento [26]. Según Naaman y Reinhart [27], el endurecimiento por deformación se produce cuando el esfuerzo a la tracción máximo posterior la fisuración de la matriz (σ pc) excede la resistencia a la tracción que produce la aparición de la primera fisura en el concreto (σcc).…”