Influence of thermally activated alum sludge ash on the near surface characteristics of multiple-blended binders concretes

摘要

This research presents the results of an investigation on the influence of thermally activated alum sludge ash (AASA) as a partial cement replacement on the near-surface characteristics of binary and ternary blended binder (TBB) concretes incorporating silica fume (SF), ground granulated blast furnace slag (GGBS), and palm oil fuel ash (POFA). All of the mixtures were prepared with a water/binder ratio and total binder content of 0.30 and 493 kg/m~3, respectively. Initial surface absorption (ISAT) and sorptivity tests were conducted at the age of 28 days. Results indicate decrease in the ISAT and sorptivity values of binary blended binders with 15% AASA cement replacement compared with the control and 20% AASA concretes. A higher replacement level of 20% AASA did not help improve inner core durability but improved surface durability characteristics. All TBB concretes performed better than the binary blends with AASA at the same replacement levels.