A THESIS SUBMITTED TO THE FACULTY OF CIVIL ENGINEERING, INSTITUTE OF TECHNOLOGY, SCHOOL OF POST GRADUATE STUDIES ARBA MINCH UNIVERSITY IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE CONSTRUCTION TECHNOLOGY AND MANAGEMENT ENGINEERING

Abstract

A building's essential building material is concrete. The most common composite components used to make concrete are water, natural sand, coarse aggregate, and a binder like cement. Alternative materials should be used for concrete because to the extensive and quickly growing use of construction materials and the amount of construction projects are being done globally. Partially substituting ecologically friendly ingredients has a big impact on overcoming high strength and low-cost concrete. This study's main objective was to experimentally investigate the combined effects of using recycled fine aggregate and waste clinical ash in place of some of the cement used to make concrete. In this study, C-25 concrete grade was designed, and its performance was assessed in the lab by substituting recycled fine aggregate with 0%, 10%, 20%, and 30% fine aggregate, and cement with waste clinical ash that was individually 5%, 10%, and 15%. The combination of the two waste materials together in matrix form and their properties were determined. The compressive strength test, split tensile strength test, and flexural strength tests were performed in the laboratory for the 7th and 28th day curing concretes and water absorption capacity were determined after 28th day curing. In addition to that resistances to sulfate attack of concrete were performed after the 56th day curing period. Individually, 5% of waste clinical ash and 10% of recycled fine aggregate in control mix construction have significant experimental performance, and the combination of 5% waste clinical ash and 10% recycled fine aggregate shows significant experimental results in the properties of compressive strength test, split tensile strength test, and flexural strength tests control mix. Therefore, the optimum amount of replacement is 5% waste clinical ash and 10% recycled fine aggregate, which gives comparable properties to the control mix.