Physical Characteristics of Incinerator Ash as a Fine Aggregate Substitute Material in Construction

Abstract

Incinerator ash is a residue from solid waste combustion that has the potential to be used as a construction material. This study aims to examine the physical characteristics of incinerator ash as a substitute for fine aggregate in construction. The incinerator ash used comes from the combustion of plastic and styrofoam waste at PT Ceria Nugraha Indotama. Physical characteristic testing includes gradation analysis referring to SNI ASTM C136:2012, specific gravity and water absorption testing referring to SNI 1970:2008, and testing the content of material passing through sieve No. 200 referring to SNI ASTM C117:2012. The results of the gradation analysis indicate that the incinerator ash belongs to Zone 3 (rather fine) and meets the fine aggregate gradation classification. The specific gravity test produces a bulk value of 1.03, SSD 1.22, and apparent 1.28, with water absorption of 19.23%. The average value of material passing through the No. 200 sieve is 34.01%, which is higher than the maximum limit of fine aggregate for concrete according to ASTM C33/C33M, which is 3–5%, thus indicating a very high fine particle content. The characterization results show that incinerator ash has a fine grain size, a lower specific gravity than natural fine aggregate, and high water absorption due to the porous structure of the material. Based on these characteristics, incinerator ash has the potential to be used as a partial substitute for fine aggregate in construction, but further research is needed to evaluate its effect on the mechanical properties of construction materials..