Structural properties and temperature effect of sintered fly ash pellets concrete

Abstract

In order to create a sustainable environment, it is essential to use industrial waste as a building construction material. For a growing nation like India, Fly Ash (FA) as a waste produced abundantly from the thermal power plants is always a significant problem. Sintered fly ash pellets produced form fly ash can be utilized as coarse aggregate in concrete, which will be considered beneficial towards sustainability of the natural resources. This current research attempts to examine the temperature effects on the structural behaviour of the concrete made from sintered fly pellets as a replacement of coarse aggregate. As sintered fly ash pellets make the concrete lighter in comparison to natural coarse aggregate concrete, the structural properties such as load deflection behaviour of beam and mechanical properties need to be investigated. In addition to structural properties, it is also essential to explore durability aspect of the same. Experimental investigation revealed that formation of shear crack is generated earlier in FA sintered pellet concrete beam in comparison to natural coarse aggregate concrete beam. However, FA pellet concrete performs better in compressive strength, split tensile strength, whereas flexural strength shows inferior strengths. Durability test that involved exposure to higher temperatures (90 °C, 180 °C & 250 °C) provides good compressive strength in case of fly ash pallet concrete. But one outstanding achievement is that the rate of gaining of strength increases from 7 days to 28 days is faster than control mix. The experimental observation recommended that FA sintered pellet concrete should be utilized in case of lighter weight concrete wherever required rather than in major structural element construction.