10-year natural carbonation data of concretes with limestone, fly ash, volcanic ash, and slag and exposed to tropical climate in India
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View abstract on PubMed
Summary
This summary is machine-generated.This study presents the first natural carbonation depth database for concrete with supplementary cementitious materials (SCMs) in a tropical climate. The data, collected over 11 years, aids in developing reliable models for reinforced concrete service life prediction.
Area Of Science
- Civil and Structural Engineering
- Materials Science
- Environmental Science
Background
- Supplementary cementitious materials (SCMs) are increasingly used to reduce the carbon footprint of Ordinary Portland Cement (OPC).
- The natural carbonation resistance of SCM-containing concrete is crucial for infrastructure durability but poorly understood, especially in tropical climates.
- Accelerated carbonation tests often fail to accurately represent real-world conditions and can alter concrete's pore structure.
Purpose Of The Study
- To present a unique long-term natural carbonation depth (dCO2) database for 45 concrete mixes with various SCMs.
- To provide data from a tropical climate (Chennai, India) to bridge the gap in current research.
- To enable the development and calibration of more accurate models for predicting concrete service life.
Main Methods
- Collected natural carbonation depth (dCO2) data over 1 to 11 years under sheltered and unsheltered tropical exposure conditions.
- Utilized phenolphthalein indicator (RILEM CPC 18) for dCO2 measurements.
- Documented detailed concrete mixture proportions, curing times, and compressive strengths.
Main Results
- The study generated an unprecedented natural dCO2 database for concretes incorporating volcanic ash, fly ash, slag, and limestone.
- Data reflects carbonation under genuine tropical environmental conditions (warm and humid).
- The database includes 45 distinct concrete formulations, offering wide applicability.
Conclusions
- This database is vital for researchers and practitioners to refine existing or create new carbonation models for tropical climates.
- Accurate natural carbonation models are essential for designing reinforced concrete structures with a defined, corrosion-free service life.
- The findings support the sustainable use of SCMs in concrete while ensuring long-term structural integrity.
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