Experimental study on hybrid fiber reinforced concrete with composite layers

Abstract

Concrete is the most frequently used material in the world because of its high easiness. The consequence of using concrete alone has become a high depravity due to its low tensile strength. In order to overthrow this drawback in concrete; fibers can be incorporated in concrete which enhances the mechanical properties. Furthermore, researchers have also been focused on different proportions of materials in different composite layers of concrete beams which further increases the mechanical property as well as static behaviour of the structural member. The main objective the present study is to investigate the influence of fibers on functionally graded concrete beams with two different types of fibers such as steel fiber and sisal fiber. In order to produce functionally graded concrete beams; mechanical properties of concrete with mono and hybrid fibers have been determined. Optimum fiber dosages of steel and sisal fibers have been determined from the mechanical property tests of mono and hybrid fiber reinforced concrete. The above-mentioned optimum fiber dosages have been determined to produce the functionally graded concrete beams with mono and hybrid fibers. Functionally graded concrete beams have been cast with one layer of mono fibers and conventional concrete, with two layers of mono fibers and conventional concrete, with one layer of hybrid fibers of total fiber volume fraction as 1% and conventional concrete and with two layers of hybrid fibers to examine the influence of fibers on flexural behaviour. Beam specimen of standard size (500mmx100mmx100mm) has been used constantly. From the mechanical property tests result it was observed that the flexural strength increases with the increase of fiber dosages until it reaches the peak compared with conventional concrete. Static behaviour of functionally graded concrete beam tests results reveals that the percentage increase is about 90.8% for the beams with different layers of fibers proportions when compared to conventional concrete.