INVESTIGATING EFFECTS OF INTRODUCTION OF CORNCOB ASH INTO PORTLAND CEMENTS CONCRETE: MECHANICAL AND THERMAL PROPERTIES

Abstract

The purpose of this study was to evaluate the benefits of replacing Ordinary Portland Cement (OPC) with Corncob Ash (CCA) blended cements. The cement industry contributes considerable amount of Carbon Dioxide (CO₂) emissions into the atmosphere. The main contribution of CO₂ emissions from cement production results from the process of creating Calcium Oxide (CaO) from limestone (CaCO₃) commonly known as the calcination process. Blending OPC with a pozzolanic material will assist in the reduction of CO₂ emissions due to calcination as well as enhance the quality of OPC. There are various pozzolanic materials such as fly ash, rice husk, silica fume and CCA that could be promising partial replacement for OPC. In this study, CCA will serve as the primary blending agent with OPC. An experiment was performed to designate an appropriate percentage replacement of CCA that would comply with specific standards of cement production. The experimental plan was designed to analyze compressive strength, workability and thermal performance of various CCA blended cements. The data from the experiment indicates that up to 10% CCA replacement could be used in cement production without compromising the structural integrity of OPC. In addition, it was found that the compressive strength and workability of the resulting concrete could be improved when CCA is added to the mixtures. Furthermore, it was shown that the introduction of 10% CCA can lead to significant reduction in thermal conductivity of the mixture.