Combined Effect of Fly Ash and Fibers on Properties of Cement Concrete

Abstract

Worldwide the production and consumption of building materials have increased in the last decades. Wastes of different types (such as fibers, powders, granules, etc.) are used for obtaining construction materials. Concrete is one of the most used materials and in time it diversified. Near the ordinary concretes today a lot of new types of concretes had occurred. Fiber reinforced concrete is a special concrete in which wastes can be used for totally or partially replacement of mix components. For studying the influence of wastes on mechanical properties of cement concrete (green concrete), different dosages of cement were replaced by fly ash and also glass fiber or polyester fiber were added. The compressive strength, flexural strength and split tensile strength were experimentally determined. According to test results, the concrete with 10% replacement of cement with fly ash and fiber presented better results of compressive strength than the concrete without fiber. Glass fiber increased flexural strengths for small dosages of fly ash. Higher dosages of fly ash and glass fiber decreased the mechanical strength. Polyester fiber had increased the values of all flexural strength of fly ash cement concrete.