Strength, fluid transport and microstructure of high-strength concrete incorporating high-volume ground palm oil fuel ash blended with fly ash and limestone powder

o improve the construction sector's sustainability, by-product materials from biomass power plants, such as palm oil fuel ash, can be utilized as an alternative mineral additive in concrete. This study evaluated the feasibility of using ground palm oil fuel ash (GPOFA) as a binary-blended binder constituent in high-volume. High-volume GPOFA (60%) was also mixed with 10% limestone powder (LS) or 10% fly ash (FA) as a ternary-blended binder to produce high-strength concrete (HSC). The workability, compressive strength, durability properties such as chloride ion penetration and water permeability were evaluated. The microstructure of the cement pastes was examined with X-ray diffraction (XRD), thermogravimetric analysis (TGA), and mercury intrusion porosimetry (MIP). Studies of concrete carbon dioxide (CO2) emissions were also conducted to evaluate environmental impact. The results indicated that incorporating high-volume GPOFA in HSC reduced the workability of concrete. However, incorporating FA could improve workability. The chloride resistance was better than the control concrete and decreased with higher GPOFA content. Adding LS and FA improved the compressive strength, chloride resistance, and water permeability compared with concrete with the same ordinary Portland cement (OPC) content. These observations are supported by the XRD, TGA, and MIP results. According to the findings, high-volume GPOFA in high-strength concrete is an environmentally friendly construction material because it decreases concrete CO2 emissions and landfill waste disposal.