STRUCTURAL APPLICATIONS OF COMPOSITES IN INFRASTRUCTURE
also being used in combination with concrete slabs to develop and test new model bridges by M. Saiidi and F. Gordaninejad at University of Nevada, Reno. Since the 1930's, glass fiber reinforced plastic (GFRP) has been considered a good substitute for steel as a reinforcement ofconcrete or to create an initial state ofcompressive stress in concrete by prestressing GFRP tendons~ Reinfofcement and prestressing of concrete are common ways to miti.gate the lo\v tensile strength of concrete in order to take advantage of its high compressive strength~ In fact, reinforced concrete is a fiber reinforced composite material in '''hieh the advantageous properties of the constituents are high tensile strength of the rebars (steel or FRP) and the high compressive strength of the concrete matrix.. Surface protection of certain types of continuous glass fibers, particularly E..glass fibers, from attacks by the environment or alkaline reaction with concrete has been accomplished by coatings, including resins. For example, a typical continuous E..glass fiber reinforced plastic rebar has a 55% glass vol.ume fraction enlbedded in a matrix ofv'inylester or isophthalic resin~ These thermoset resin systems have ex~ ceHent resistance to corrosion a.nd impact, are good electrical and thermal insulators, are easy to manufacture, and are cost effective~ Thermoplastic rebars, which are more expensive than thermosets, have a potential for reshaping and \velding in the field which motivates current investigation oftheir potential applications in constnlction# Aramid fibers (e.g#, DuPont's Kevlar® 29, 49, 149) with higher tensile strength (3~62 GPa) and stiffness (124 G·:Pa for Kevlar@ 49) than glass fibers are being used to devel.op high strength rebars and cables by DoS. and Japanese manufac~ turerso AraIuid fibers have good chemical resistance to sol .. vents, dilute ac...i.ds~ and bases, as well a..1O) excellent fatigue strength and low relaxationo Carbon fiber reinforced plastic rebars and seven wire strands (cables) \vith higher stiffness than glass or aramid fiber rehars are also manufactured as reinforcing or prestressing eleluents for structural appHca~ tions, Ho\vever, carbon fiber rebars and cables are even more expensive than aramid or glass rebars, Chopped fiber rein-· forced plastic rods are being manufactured by extrusion~ 'fhesr.
EFFECT OF FIBER LOADING ON MECHANICAL BEHAVIOR OF CHOPPED GLASS FIBER REINFORCED POLYMER COMPOSITES
Chopped strand mat glass fibre reinforced polymer composites is widely used in many industrial applications particularly in the automotive industry due to advantages such as low weight, ease of processing, price and noise suppression. Although a great deal of work has been reported in the literature which discuss the mechanical behavior of fiber reinforced polymer composites, however, very limited work has been done on effect of fiber loading on mechanical behavior of chopped glass fiber reinforced epoxy composites. Against this background, the present research work has been undertaken, with an objective to explore the potential of chopped glass fiber as a reinforcing material in polymer composites and to investigate its effect on the mechanical behavior of the resulting composites. The present research work thus aims to develop chopped glass fiber based polymer composites and study the influence of fiber loading on their mechanical behavior. Finally the morphology of fractured surfaces is examined by using scanning electron microscopy (SEM) after tensile, impact and flexural tests.
GLASS-FIBER-REINFORCED COMPOSITES IN BUILDING CONSTRUCTION
Glass-fiber-reinforced plastic composites have had limited use as structural components in building construction. To realize the full potential of these materials and increase their use, their outstanding features must be emphasized. In developing composite components, it is essential to combine expertise in the disciplines of plastic and reinforcing materials, structural design and fabrication techniques. Efficiently designed composite components and a case history are presented to demonstrate typical practical applications.