The flexural strength assessment of reinforced concrete beams using rubberised concrete

Abstract

With the problem of waste land filling increasing every year, one should find a solution to reduce waste, one of which being tyre rubber waste. With recent legislations and directives the European Union have adopted, waste tyres cannot be landfilled and therefore alternative disposal routes have to be found. One of the major industries found in Malta is the construction industry, with concrete being one of the main materials used in building construction. Waste tyres could be used in the construction industry as a substitute for stone aggregate in concrete, solving the growing problem of waste disposal and also reducing the usage of natural rock which is a depleting resource. This study is a continuation of the study conducted by Scicluna (2010), in which natural aggregate, both fine and coarse, was replaced by rubber particles. The mixes with the highest compressive strengths achieved by Scicluna (2010) were chosen to study the flexural strength of reinforced rubberised concrete beams, and these were compared to the control mix designed. Cube compressive strength tests were carried out at 3, 7 and 28 days and four point flexural tests on the reinforced beams were carried out at 28 days. The beams measured 200mm in width, 250mm in depth and 4000mm in length. Although there was a reduction in compressive and flexural strength, the rubberised concrete mixes exhibited ductile properties especially when using shredded rubber chips. The rubberised concrete beams exhibited also larger deflections, smaller crack widths and fewer amounts of cracks along the length of the beam.