Next generation UHPFRC for sustainable structural applications

Emmanuel Denarié, Amir Hajiesmaeili
2018
Conference paper

Abstract

Over the last few decades, ever-increasing demands of society to the built environment have continually increased consumption of energy and materials for the construction and maintenance of structures. Meanwhile, Strain Hardening Ultra High-Performance Fiber Reinforced Concrete (SH-UHPFRC) have the potential to be one of the solutions to contain the explosion of maintenance costs (Economy and Environment), considering their extremely low permeability associated to outstanding mechanical properties and load bearing efficiency compared to deadweight. The objective of this research is to further improve the already established concept of UHPFRC application for rehabilitation. This paper reports firstly on the development and validation of new low Embodied Energy (EE) SH-UHPFRC mixes with 50 % clinker replacement by Supplementary Cementitious Materials and replacement of steel fibers by ultra-high molecular weight polyethylene (UHMW-PE) ones. In a second step, the mechanical and protective properties of the mixes are investigated with a special emphasis on their quasi-static tensile response, and transport properties. Finally, the dramatic improvement in terms of reduction of EE and deadweight of the proposed mixes is demonstrated.

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