Fresh Properties of Self-Consolidating Expired Cement-Fly Ash Cold Bonded Lightweight Aggregate Concrete With Different Mineral Admixtures

Abstract

The experimental program evaluated the fresh properties of self-consolidating lightweight concretes (SCLC) produced from expired cement EC cold-bonded lightweight coarse aggregates (ALA) with silica fume (SF) and fly ash (FA). Twelve mixtures of SCLC were prepared, the binder in the control mix was just Portland cement (PC), whereas other mixes included binary and ternary of (PC), 20% of (FA), and/or (10%) of (SF) with (0%, 50%, and 100%) as partial replacement of (ALA) with coarse natural aggregates. Fresh features of (SCLC) were evaluated by measuring their slump flow diameter, T500 slump flow time, V-funnel flow time L-box height ratio, and column segregation, (SCLC) with and without mineral admixtures have their fresh characteristics compared. It was found that increasing the quantity of ALA replacement resulted in a reduction in the amount of superplasticizer required to obtain a constant slump flow diameter of SCLC. Combining (SF) and/or (FA) lowered both the V-funnel flow time and the slump flow time, whereas the L-box height ratio increased from (0.82) to (0.86) with the addition of fly ash for reference mix. With the combined action of mineral admixtures, the percentage of column segregation decreases by (16.7%) compared with the reference mix. The maximum slump flow was (792) mm with a mix of (M6).