The experimental work reported in this paper was carried out to study the feasibility of using Glass fibres in concrete as fibre reinforcement. This composite material, which possesses unique qualities of strength, can partly replace the conventional reinforced cement concrete, which is popular and widely used in building construction or in the application. It was originally developed for insulating electrical wiring and later found to have excellent fibre forming capabilities, and is now used almost exclusively as the reinforcing phase in the material commonly known as fiberglass. This paper presents the results and conclusion of an experimental investigation on the strength properties of concrete using glass fibre . Concrete specimens were cast with and without fibres and tested under compression, split tension and flexure as per relevant Indian standard specifications. M₃₀ grade of concrete was designed using IS method of mix design. A total of 50 cubes for compressive strength, 50 cylinders for split tensile strength and 50 beams for flexural strength were cast and tested. Fibre contents used in this experimental work were 0%, 1%, 2%, 3%, 4%, 5% & 6% by weight of aggregate. Water cement ratio adopted has 0.42. The glass fibres used in this work has an aspect ratio taken in the range of 50 − 70. Workability of the concrete was checked with slump cone and consistency by compaction factor test for various percentage fibre additions in the concrete. A tendency towards balling or formation of fibre nodules is a serious problem in FRC and it is avoided in this experimental work by addition of fibre in stages. Tests were conducted at the end of 7 days, 14 days, and 28 days curing. Test results indicate that addition of glass fibres in concrete enhances the strength markedly. It was found that even 1.0% of fibre content by weight of concrete showed improvement in compressive strength by 7.61 %. Also percentage increase in the strength-to-weight ratio achieved by incorporating glass fibres in concrete is higher than those concrete without glass fibres.

Key words: Fibre reinforced concrete, Composites, Glass Fibres ,flexural strength, compressive strength