Durability properties of self-compacting concrete developed with fly ash and ultra fine natural steatite powder

Abstract

One of the major reason people choose concrete structure is because of its durable nature. This paper brings out the experimental results on durability study of ternary blended Self compacting concrete (SCC). The minerals used in this study are fly ash (FA) - as partial replacement to cement and ultra-fine natural steatite powder (UFNSP) - as an addictive. FA is used as a partial replacement to cement in SCC at 10% and 20% by weight. In both of this replacement level UFNSP were added in various percentages like 0%, 5%, 10%, 15%, 20% and 25% by weight of powder content. Hence totally thirteen sets of specimens were casted and various durability studies like initial water absorption, saturated water absorption, effective porosity, sorptivity, rapid chloride penetration and bulk diffusion were studied. In this study the steatite and fly ash particles mainly contribute as filling material hence at higher percentage the same mitigates the voids, which is also noted in the calculation of effective porosity. This experimental investigation is further supported by the scanning electron microscope images. Increasing the replacement level, arrested the microcracks thereby improved the microstructure and showcased very less voids. The SEM images also indicated the formation of magnesium silicate hydrate gels which also contributed to the enhancement of durability properties.

Keywords

• Self compacting concrete
• Durability
• Ultra fine natural steatite powder
• Fly ash
• Cement
• SEM