Evaluating the Impact of Specimen Shape and Size on the Strength Characteristics of Recycled Aggregate Concrete

The use of green concrete is increasing worldwide.The growing global demand for utilizing recycled materials in concrete mixes to enhance sustainability makes it important to study the strength properties and behaviour of recycled aggregate concrete (RAC).While the impact of specimen shape and size on the compressive and flexural strength of normal concrete is well-documented, their effects on concrete mixes containing recycled aggregate and ceramic waste are not yet defined.This paper studies the effect of specimen shape and size on the strength properties of RAC by conducting compression tests on cubes and cylinders and performing four-point flexural tests on beams.Locally available recycled coarse aggregate, ceramic fine aggregate, and ceramic waste powder were used to develop the recycled aggregate concrete.Compression tests were conducted on standard cubes, standard cylinders, and halfscale cylinders.Flexural tests were performed on beams sized 150 mm150 mm460 mm and 75 mm75 mm230 mm.Based on the experimental results, it was found that the specimen shape and size significantly affect the strength properties of RAC, and the conversion factors differ from those of normal concrete with the same strength.Additionally, a preliminary relationship between the compressive strength and flexural strength of RAC is suggested.