Fibre-Reinforced Concrete: Structural Design for Reducing Carbon Footprint

Abstract

The use of fibres in concrete has proven to enhance concrete’s structural performance. Among all other fibres, steel fibre-reinforced concrete is one of the most widely used materials for both structural and non-structural applications. However, as a material that presents enhanced structural performance, its potential to reduce carbon emissions must be analysed to reflect these advantages. Most studies on the life cycle assessment of concrete products use a mass-based functional unit, which ignores the primary functionality of fibre-reinforced concrete in reducing carbon emissions. This study aims to analyse the carbon emissions and potential savings in the use of steel fibre-reinforced concrete in structural members (slabs and beams) using a whole life cycle assessment methodology that includes the benefits/ load after the end of life. This study will link the structural, material, and environmental performance of concrete.
This study provides an in-depth assessment of the carbon footprint of concrete using various methodologies. A cradle-to-grave approach, which considers the benefits/ loads beyond the system boundary, was performed to compare the embodied carbon of conventionally reinforced concrete and steel fibre-reinforced concrete beams and slabs using a functional unit that considers the structural performance of concrete. The methodology used for this study involved the design and analysis of conventional reinforced concrete beams and slabs, and steel fibre-reinforced concrete beams and slabs using a Finite Element Analysis software (SCIA Engineer) and a life cycle assessment using standardised guidelines and approaches. A life cycle assessment tool (SimaPro) was also used to assess the performance of these structural elements and the various process contributions to produce the elements. The initial cost implications of using steel fibres are also analysed and discussed.
The results obtained in the study were analysed, and the effects of variables such as compressive strength, span, and load capacity were discussed. The results showed that, generally, the embodied carbon of concrete increases with increasing compressive strength and span. Interestingly, the embodied carbon of concrete decreases with increasing load in concrete elements. This result was linked to the improvement in material efficiency and utilisation. The results show that in certain cases, the addition of steel fibres as a reinforcing material to concrete not only improves the structural performance of concrete but also its environmental performance.
The findings from this study have significant implications for building a sustainable environment and emphasise the need for a thorough assessment of structural materials from the standpoint of environmental performance. By revealing the potential of steel fibres in the structural design of concrete elements, this study will help engineers develop the necessary tools for designing a low-carbon future-built environment.

Date of Award	14 Apr 2026
Original language	English
Awarding Institution	University of Portsmouth
Supervisor	Stephanie Barnett (Supervisor) & Kenneth Awinda (Supervisor)