Study of C-S-H Formation of Cemented Sediment Brick

This paper presents an experimental study of chemical structure formation in newly developed sediment bricks. Morphology analysis was conducted by Scanning Electron Microscope (SEM) images to observe morphological structure and amorphous material while mineralogy analysis through Energy Dispersive Spectroscopy (EDS) and X-Ray Diffraction (XRD) to determine amount of the amorphous materials. C-S-H formation that formed a dense material was observed in Mix 4, which made up from 20% weight of sediment-sand, 70% weight of sediment-silt and stabilized by 10% weight of cement content, which was identified to be the best mix in earlier publication [1]. Higher content of calcite in Mix 4 shows existance of carbonates that indicates lower C-S-H formation compared to Mix 1, which has higher cement content. Meanwhile, larger amount of SiO₂ in Mix 6 does not indicate higher production of C-H-S. This is verified by SEM images whereby unreacted sediments were observed in Mix 6. This study showed that increment of sediment content disturbed the production of hydration products. In addition, C-S-H formation is not solely verified by amount of SiO₂, it has to also verify through SEM images since SiO₂ can also be the unreacted raw materials.