Sugar cane bagasse ash from a high-efficiency co-generation boiler as filler in concrete

Bagasse ashes from high efficiency co-generation boilers have dominant filler effect in concrete from a greatly reduced pozzolanic activity because of quartz polymorph phase changes to a-quartz, rather than the often-reported alpha-cristobalite for bagasse derived silica. Sugar cane bagasse ash used as filler in concretes provided substantial improvements to compressive strengths at up to approximate to 20%. These combined filler effect and limited pozzolanic activity improved the acid resistance as measured by both mass loss and compressive strength tests. Improved acid resistance suggests pore filling and lowered permeability from the filler effects, whereas the limited pozolanic may be sufficient to shift cement chemistry to more acid resistant silicates mineral systems compared to aluminate minerals (e.g., C(3)A to C2S). Similarly, drying shrinkage improved. However, in contrast the rapid chloride permeability tests indicate increased chloride ingress, suggesting increased permeability, but these maybe possibly misleading results generated from the superplasticizer. (C) 2017 Elsevier Ltd. All rights reserved.