EFFECT OF REINFORCING STEEL FIBER LENGTH ON COMPRESSIVE STRENGTH OF CONCRETE USING RECYCLED COARSE AGGREGATES

Abstract

This paper presents an experimental results to evaluate the compressive strength of concrete using recycled coarse aggregate, reinforced with steel fibers. The steel wire lengths used are 5 mm, 10 mm and 13 mm, with bending at both ends. Concrete using recycled raw aggregates is designed to have a strength grade of B15. The content of steel fiber used includes 0,5% and 1%. Samples were 15x15x15 cm in size and were compressed at 28 days of age. Compressive strength of concrete using 10% recycled aggregate increases with increasing fiber length. This growth is linear. Compared with the value of compressive strength of concrete when using 5 mm steel fiber, the result recorded an average increase of 9.5% when using 10 mm steel fiber and 12.92% when using 13 mm steel fiber. The obtained results are also consistent with the results published by some authors when studying the compressive strength of UHPFRC when increasing the fiber length.