Studies on combined effect of graphene oxide and mineral admixtures in concrete

Abstract

In recent times, the usage of agricultural and industrial waste in construction industry becomes more popular. These locally accessible materials gave a better solution to environmental issues and attain high strength in buildings with low cost. Rice Husk Ash (RHA) with Graphene Oxide (GO) as 50% cement replacement in concrete were used and analysed in this study. Also, this samples were mould as reinforced concrete beam specimens and tested for their flexural behaviour. Eleven cube samples were made with 4.9% RHA-0.1% GO, 9.8% RHA-0.2% GO, 14.7% RHA-0.3% GO, 19.6% RHA-0.4% GO, 24.55% RHA-0.5% GO, 29.4% RHA-0.6% GO, 34.3% RHA-0.7%GO, 39.2% RHA-0.8% GO, 44.1% RHA-0.9%GO and 49% RHA-1% GO. Control concrete mix with 100% OPC were used to compare the results after 7,14 and 28 days for compressive strength, modulus of elasticity, flexural strength etc. Fresh concrete properties such as slump, bulk density and entrained air content were tested for eleven concrete mixes and SEM images for materials and cured concrete were presented in this study. Seven concrete mixes were used for beam specimens that is up to 30% RHA-GO replacement and tested for deflection, load carrying capacity and crack pattern. As a result, 25 to 30% RHA-GO mix can be used as cement replacement in concrete. newlineAlso, the proposed result was compared with other mineral admixtures combinations such as rice husk ash with silica fume and rice husk ash with fly ash. Using mineral admixtures in combinations helps to overcome some disadvantages of using mineral admixtures in concrete. newline newline