Performance evaluation and environmental sustainability assessment of ferrock-infused concrete

Developing a new type of building material is essential for reducing the carbon footprint of cement in sustainable concrete. This study aims to investigate Ferrock, synthesized from industrial waste, as a partial replacement for cement in concrete. Ferrock was incorporated at dosage levels of 10-50%, with increments of 10% by weight of cement. The mixes were tested for workability, compressive strength, split tensile strength, flexural behaviour, rebound hammer response, rapid chloride penetration test, and elevated temperature resistance up to 600 °C. Microstructural characteristics were examined using Scanning Electron Microscopy and Fourier Transform Infrared Spectroscopy. Pore analysis of the Scanning Electron Microscopy image was performed using ImageJ to assess pore size and area. Response Surface Methodology was applied to optimise the dosages of cement, Ferrock, and oxalic acid, and a predictive strength model was developed. Results show that 10% Ferrock replacement produced the most favourable mechanical performance, with noticeable reductions in strength at higher replacement levels. Durability outcomes also improved at 10% Ferrock, demonstrating significantly lower chloride permeability and enhanced thermal stability compared to control and higher-percentage mixes. An environmental sustainability assessment was conducted under a cradle-to-site boundary for critical indicators, showing that incorporating Ferrock reduces embodied energy, global warming potential, and overall material use costs. Overall, the findings confirm that a 10% Ferrock addition offers an optimal balance of mechanical performance, durability, and environmental benefits, supporting its potential as a low-carbon, cost-effective material that promotes circular economy practices in concrete construction.