Coal bottom ash and its applications in cement and concrete technologies: a review

Abstract

In the context of the mounting crisis of waste management and environmental sustainability, coal bottom ash (CBA) emerges as a pioneering solution in the field of construction. This study, which is a pioneering investigation, delves into the transformative impact of integrating CBA into the fabric of various concrete compositions, which range from traditional mortar to avant-garde geopolymer concrete. A comprehensive evaluation of mechanical properties, including compressive strength, flexural strength, and modulus of elasticity, is conducted alongside a spectrum of durability indicators such as water absorption, chloride ion resistance, and sulfate fortitude. Benchmarks set by global standards such as ASTM and EN serve as our yardstick, revealing that a strategic substitution of up to 10% of sand with CBA not only aligns with these rigorous norms but occasionally surpasses them. For cement, concrete, and geopolymer, the optimal replacement levels of CBA are between 10 and 30%. This enhances mechanical properties and promotes environmental sustainability. Our findings demonstrate the dual benefits of CBA: enhancing the structural integrity and durability of concrete while promoting ecological stewardship. This study not only validates the suitability of CBA as a superior construction material but also encourages the construction industry to pursue a more sustainable and waste-minimizing future.