Properties of MSWI Fly Ash Slag-blended Cement Concrete

Abstract

Municipal solid waste incinerator (MSWI) fly ash was melted into slag and then pulverized to generate particle sizes of less than 38 μm in diameter (sieve #400) for experimental studies. Several slag-blended cement concrete (SBCC) specimens 10 cm in diameter and 20 cm in height were molded using 20% cement replacement with slag powder. Then, three water/cementitious (w/c) ratios, namely 0.36, 0.52 and 0.68, were selected to test the specimens for slump, setting time, compressive strength and durability. The compressive strengths of specimens of various ages were compared with those of ordinary Portland cement concrete (OPCC) specimens. The results reveal that the compressive strengths of the SBCC specimens were lower than those of the OPCC specimens at an early stage and became similar to those of the OPCC specimens at the age of 28 days. Moreover, the compressive strengths of the SPCC specimens are 100-113% and 105-118% those of the OPCC specimens after 56 and 90 days, respectively. The slumps (i.e. workability) and setting times for both the SBCC and OPCC specimens were similar. Our test results show that MSWI slag-blended cement concrete is usable for practical applications and can be applied to the concrete pavement.