GRA - GLOBAL RESEARCH ANALYSIS X 85 Volume : 2 | Issue : 2 | Feb 2013 • ISSN No 2277 - 8160 Research Paper Engineering A Study on Glass Fibre as an Additive in Concrete to Increase Concrete Tensile Strength Ronak Prakashkumar Patel Student of final year M.E. in Construction Engineering & Management, B.V.M. Engineering College, Vallabh Vidyanagar-Gujarat-India Jayraj Vinodsinh Solanki Student of final year M.E. in Construction Engineering & Management, B.V.M. Engineering College, Vallabh Vidyanagar-Gujarat-India Jayeshkumar Pitroda Assistant Professor and Research Scholar, Civil Engineering Department, B.V.M. Engineering College, Vallabh Vidyanagar-Gujarat-India - The present day world is witnessing the construction of very challenging and difficult civil engineering structures. Glass fiber (also spelled glass fibre) is a material consisting of numerous extremely fine fibers of glass. Quite often, concrete being the most important and widely used material is called upon to possess very high strength and sufficient workability properties. Efforts are being made in the field of concrete technology to develop such concretes with special characteristics. Researchers all over the world are attempting to develop high performance concretes by using fibres and other admixtures in concrete up to certain proportions. Glass-fibre reinforced concrete (GRC) is a material made of a cementatious matrix composed of cement, sand, water and admixtures, in which short length glass fibres are dispersed. It has been widely used in the construction industry for non-structural elements, like façade panels, piping and channels. GRC offers many advantages, such as being lightweight, fire resistance, good appearance and strength. To increase the applications of Glass Fibre Reinforced High-Performance-Concrete (GFRHPC) in India, greater understanding of GFRHPC produced with locally available materials and indigenously produced mineral admixtures is essential. ABSTRACT KEYWORDS: glass fibre, additive, concrete, rigid pavement, utilization, tensile strength INTRODUCTION Glass wool, which is commonly known as “fiberglass” today, however, was invented in 1938 by Russell Games Slayter of Owens-Corning as a material to be used as insulation. It is marketed under the trade name Fiberglas, which has become a genericized trademark. Glass fiber also called fiberglass. It is material made from extremely fine fibers of glass Fiberglass is a lightweight, extremely strong, and robust material. Al- though strength properties are somewhat lower than carbon fiber and it is less stiff, the material is typically far less brittle, and the raw materi- als are much less expensive. Its bulk strength and weight properties are also very favorable when compared to metals, and it can be easily formed using molding processes. Glass is the oldest, and most familiar, perfor- mance fiber. Fibers have been manufactured from glass since the 1930s. TYPES OF FIBER Steel fiber, Glass fiber, Polypropylene Fiber, Asbestos fiber, Organic fib- er, Vegetable fiber, Carbon fiber, Polyester fiber etc. are various types of fiber available in world. Fiber technology is one of the fastest updating technologies today. There are currently 2,00,000 metric tons of fibers used for concrete reinforcement. Figure 1 Fiber used in concrete reinforcement in world Source: Fly ash utilization in construction – presents status & future prospects TYPES OF GLASS FIBER As to the raw material glass used to make glass fibres or nonwovens of glass fibres, the following classifica- tion is known: TABLE: 1 TYPES OF GLASS FIBER A-glass With regard to its composition, it is close to window glass. In the Federal Republic of Germany it is mainly used in the manufacture of process equipment. C-glass This kind of glass shows better resistance to chemical impact. E-glass This kind of glass combines the characteristics of C-glass with very good insulation to electricity. AE-glass Alkali resistant glass. Generally, glass consists of quartz sand, soda, sodium sulphate, potash, feldspar and a number of refining and dying additives. The characteris- tics, with them the classification of the glass fibres to be made, are de- fined by the combination of raw materials and their proportions. Textile glass fibres mostly show a circular. PROPERTIES OF GLASS FIBER • Thermal Glass fibers are useful thermal insulators because of their high ratio of surface area to weight. However, the increased surface area makes them much more susceptible to chemical attack. By trapping air within them, blocks of glass fiber make good thermal insulation, with a ther- mal conductivity of the order of 0.05 W /(m·K). • Tensile The strength of glass is usually tested and reported for “virgin” or pris- tine fibers—those that have just been manufactured. The freshest, thinnest fibers are the strongest because the thinner fibers are more ductile. The more the surface is scratched, the less the resulting tenac- ity.  TABLE: 2 PROPERTIES OF GLASS FIBRE Fiber type E-glass S-2 glass Tensile strength (MPa) 3445 4890 Compressive strength (MPa) 1080 1600 Density (g/cm3) 2.58 2.46 Thermal expansion µm/(m°C) 5.4 2.9 Softening T (°C) 846 1056 Price Rs./kg 100 1000 Source: http://en.wikipedia.org/wiki/Glass_fiber