Effect Of Corn Cob Ash And Locust Bean Pod Ash On The Mechanical Properties Of Concrete

Abstract

The Portland cement production is a highly energy-intensive process and the current trend in concrete research is towards finding alternative materials that can partially or fully replace cement. Supplementary cementitious materials (SCM) are important in producing high-strength and high-performance concrete. This study aims to investigate the effect of corn cob ash and locust bean pod ash on the mechanical properties of concrete. The concrete mix of 1:2:4 and a water cement ratio of 0.5 was blended with 5–30% pozzolanic materials individually and combined, and the concrete cured at 7, 14, 28 and 56 days. The specific gravity of Corn cob ash (CCA) and (Locust Bean Pod Ash) LBPA is 2.25 and 2.33 respectively. Corn cob ash and locust bean pod ash are pozzolanic material having satisfied the requirement of ASTM C618-05. It is observed that the workability of fresh concrete is reduced as the dosages of CCA and LBPA increase in the mixture. Moreover, the compressive and flexural strengths at 10% of CCA or CCA/LBPA gave similar strength with the control concrete, at 28 and 56 days respectively. Furthermore, the density and water absorption of concrete were reduced with increasing percentage of CCA and LBPA in concrete. It can be concluded that 10% CCA and LBPA as replacement of cement, results in improved performance of concrete. The research recommends that 10% CCA and LBPA as cement replacement individually or in the blend are the optimum percentages for structural applications which will lead to strong and quality concrete, and also help reduce the use of cement.