'Effective use of fly ash as a binder in concrete pavement: A case study of U.A.E. airport

Concrete pavements are essential for modern airport infrastructure's strength, longevity, and load capacity. A precise relationship between laboratory and field strength is essential to guarantee structural integrity. Thorough testing is necessary to verify real-world performance, even with standardized mix design standards. Although fly ash-modified concrete has been well recognized for its increased sustainability and durability, laboratory and in-situ strength variations make it challenging to predict real-world performance. In this work, laboratory performance tests were used to compare and assess the performance of fly ash-modified concrete mixtures and field cores produced in the lab and the field for use in an airport pavement application in the United Arab Emirates (U.A.E). This study employed an experimental approach, including 15% fly ash replacement levels under varied curing conditions, to assess their influence on strength development. Specimens underwent controlled laboratory testing, and core samples from the actual pavement site were tested to compare the laboratory test results with the field data. The field core compressive strength results showed a steady increase in strength with time, varying from 27MPa at 7 days to 41MPa at 90 days. This confirms that fly ash improves strength and durability over the long term, and curing greatly impacts early-age strength. Also, the visual inspection verified the lack of defects, while rebound hammer testing further confirmed the pavement's consistency and dependability, confirming the efficiency of the mix design and construction process. Thus, incorporating fly ash as a cement substitute in concrete pavement production satisfies field strength and durability requirements with minimal discrepancies and helps achieve U.A.E sustainability goals by lowering conventional cement-based concrete's carbon footprint in the construction industry.