Work

Enhancing mechanical and durability properties of recycled concrete aggregates (RCA) through large-scale CO2 carbonation treatment

Year: 2025

Type: article

Abstract: This study investigates the mechanical and durability performance of recycled concrete aggregates (RCA) after large-scale carbonation treatment using carbon dioxide (CO2). RCA obtained from a local producer in Nebraska, USA, was subjected to controlled carbonation in a 1-ton capacity carbonation chamber under varying conditions of initial CO2 pressure, treatment duration, aggregate volume, and relative humidity. Mechanical and physical properties were evaluated through specific gravity, water absorption, aggregate crushing value (ACV), Los Angeles (LA) abrasion, and freeze-thaw (F-T) resistance tests. Results show that carbonation did not significantly alter bulk properties such as specific gravity and water absorption but substantially improved mechanical and durability performance. Carbonation reduced ACV by up to 20%, LA abrasion mass loss by ~17%, and F-T mass loss by comparable margins, confirming enhanced resistance to crushing, wear, and freeze-thaw cycles. The improvements were most strongly correlated with CO2 consumption per RCA mass and treatment duration, while optimal efficiency was observed at 50-60% of relative humidity. Statistical analysis further identified CO2 consumption per RCA mass and treatment duration as the most influential parameters across all tests. These findings highlight the dual benefit of carbonation in strengthening RCA while sequestering CO2 and suggest practical guidelines for optimizing treatment conditions to achieve both mechanical and durability enhancement and environmental sustainability.

Source: Construction and Building Materials

DOI: 10.1016/j.conbuildmat.2025.144855

Authors: Hossein Sousanabadi Farahani, Amin Hosseini Zadeh, Miras Mamirov, Jiong Hu, Chris Hawkins, Seunghee Kim

Institution: University of Nebraska–Lincoln

Language: English

Topic: Recycled Aggregate Concrete Performance

Subfield: Building and Construction

Field: Engineering

Domain: Physical Sciences

SDGs: Responsible consumption and production, Climate action

Open Access status: hybrid

Estimated APC paid: $4,540