Permeation of Iron Slag and Recycled Aggregates Concrete with Microstructural Characteristics

Construction and demolition wastes can be used as recycled aggregates (RA) in development of concrete. Iron slag (IS) has further addeda vision towards its successful replacement of fine aggregates (FA) in non-conventional concrete. This study investigates the permeation potential of structural grade concrete containing IS and RA as alternative for FA and coarse aggregates (CA) respectively. The CA have been replaced with RA up to 100% while FA has been substituted with the fixed amount of IS (i.e. 30%). After achieving of desired strength criterion, concrete mixes have been tested for resistance towards water, salts and gas permeation. Further, the effect of permeation has also been related with the scanning electron microscopic (SEM) images. The findings have revealed that both IS and RA resulted in significant variation towards water (64%), salt (-13%) and gas (47%) ingression making concrete permeable for higher replacements. However, the findings have been reversed for lower order replacements. The diverse geometry of hydration compounds as noted in SEM images has also confirmed the potential utilization of IS and RA in the development of non-conventional concrete.