Recycled textile and cardboard fibres reduce concrete's carbon footprint by 3.38% and cost by 2.56%

Why It Matters

This research offers a practical pathway for the construction industry to reduce its substantial environmental impact. By utilizing waste materials as functional components, designers and engineers can develop more sustainable building materials that are both cost-effective and environmentally responsible.

Key Finding

A specific mix of concrete using recycled textile and cardboard fibres (KFT) performs as well as traditional concrete but is less carbon-intensive and cheaper to produce, with better potential for reuse and recycling.

Key Findings

• Tex-crete with 2.5% textile fibres and treated kraft fibres (KFT mix) shows comparable compressive and tensile strength to traditional concrete.
• The KFT mix design results in a net reduction of 3.38% in carbon emissions and 2.56% in production costs.
• The KFT mix achieved the highest circularity score (0.44) based on reuse, repair, and recycling potential.
• Transportation distance and energy consumption in fibre processing are critical factors affecting emissions.

Research Evidence

Aim: To assess the carbon emissions, cost implications, and circularity potential of concrete incorporating recycled textile and cardboard fibres compared to conventional concrete.

Method: Life Cycle Assessment (LCA) and Monte Carlo simulations

Procedure: A cradle-to-gate LCA was conducted to compare carbon emissions and costs of different Tex-crete (concrete with recycled fibres) mix designs against traditional concrete. A circularity index was developed and applied. Parametric analysis using Monte Carlo simulations was performed to identify key influencing factors.

Context: Construction materials, concrete production, circular economy

Design Principle

Waste materials can be valorized as functional components in new products, contributing to a circular economy and reducing environmental impact.

How to Apply

When designing concrete structures, explore the feasibility of incorporating treated recycled textile and cardboard fibres, performing an LCA to quantify environmental benefits and cost savings.

Limitations

The study focuses on specific mix designs and case studies; broader validation across different applications and fibre types may be needed. Long-term durability and performance in diverse environmental conditions require further investigation.

Student Guide (IB Design Technology)

Simple Explanation: Using old clothes and cardboard in concrete can make it greener and cheaper without making it weaker.

Why This Matters: This research shows how designers can make construction more environmentally friendly by using recycled materials, which is a key aspect of sustainable design.

Critical Thinking: To what extent can the findings of this study be generalized to different types of construction projects and geographical locations, considering variations in waste availability and processing infrastructure?

IA-Ready Paragraph: This research by Sandanayake et al. (2025) demonstrates that incorporating recycled textile and cardboard fibres into concrete mixes, specifically the KFT design, can lead to a 3.38% reduction in carbon emissions and a 2.56% decrease in production costs, while maintaining comparable structural performance to traditional concrete. This highlights the potential for waste valorization in construction materials to support circular economy principles and reduce environmental impact.

Project Tips

• When selecting materials, consider their environmental impact and potential for recycling.
• Investigate the use of waste materials as substitutes for virgin resources in your design projects.
• Quantify the environmental benefits (e.g., carbon footprint reduction) and cost savings of your material choices.

How to Use in IA

• Reference this study when discussing the environmental impact of material choices in your design project.
• Use the findings to justify the selection of sustainable materials and to quantify their benefits.

Examiner Tips

• Demonstrate an understanding of the environmental impact of material choices.
• Show how you have considered circular economy principles in your design.
• Quantify the benefits of your design decisions where possible.

Independent Variable: ["Type and percentage of recycled fibres (textile, cardboard)","Fibre treatment methods"]

Dependent Variable: ["Compressive strength","Tensile strength","Carbon emissions","Production costs","Circularity index"]

Controlled Variables: ["Cementitious material content","Aggregate type and proportion","Water-cement ratio","Curing conditions"]

Strengths

• Employs a comprehensive LCA approach.
• Introduces a novel circularity index for material assessment.
• Utilizes Monte Carlo simulations for robust parametric analysis.

Critical Questions

• What are the potential health and safety implications of processing and using recycled textile fibres in construction?
• How does the long-term durability and performance of Tex-crete compare to conventional concrete under various environmental stresses?
• What are the economic barriers to widespread adoption of Tex-crete, and how can they be overcome?

Extended Essay Application

• Investigate the feasibility of using locally sourced waste materials in construction projects, conducting a comparative analysis of environmental impact and cost.
• Develop and test a novel composite material incorporating recycled content, evaluating its performance against established benchmarks.

Source

Tex-Crete—Carbon and Cost Assessment of Concrete with Textile and Carboard Fibres—Case Studies Towards Circular Economy · Applied Sciences · 2025 · 10.3390/app15136962