Influence of incorporation of rice husk ash and coarse recycled concrete aggregates on properties of concrete

•Influence of rice husk ash in normal and recycled aggregate concrete was studied.•No substantial effect on properties of concrete was detected up to 10% RHA.•Use of 10–15% RHA and 100% RCA in concrete was recommended. The present research work has been carried out for accessing the effect of utilisation of 100% coarse recycled concrete aggregates and 0–35% rice husk ask (RHA) in designing concrete mixes. For this, 5%, 10%, 15%, 20%, 25%, 30% and 35% of rice husk ash has been introduced in natural aggregate concrete (NAC) and recycled aggregate concrete (containing 100% coarse recycled concrete aggregates) as replacement of cement. Different properties of aforementioned designed concrete mixes such as workability, 7, 28 and 90 days compressive strength, spilt tensile and flexural strength, modulus of elasticity, non-destructive parameters (rebound number and ultrasonic pulse velocity), water absorption, density, volume of voids has been determined. The analysis of experimental results depicts that the behaviour of concrete substantially is influenced by the incorporation of coarse recycled concrete aggregates and rice husk ash in concrete. However, concrete mixes containing 100% coarse recycled concrete aggregates and 10–15% rice husk ash satisfies the design requirements for application in construction industry.