Analysis of the Flexural Behaviour of Glass Fiber-Reinforced Plastic

Glass fibre reinforced polymer (GFRP) profiles are finding increasing applications in civil engineering structures, owing to the several advantages they offer over traditional materials. However, due to the combustible nature of their polymer matrix, there are well-founded concerns about their behaviour at elevated temperature and under exposure to fire. These concerns are hindering the widespread acceptance of GFRP profiles, particularly in buildings, which need to comply with relatively strict requirements in terms of fire reaction and fire resistance behaviour. Even though the GFRP structural shapes are available, the designers of such component are facing problem in the design since reliable design criteria is lacking. Thus there is an urgent need to understand the behaviour of the GFRP structures and their components under various types of loading and support conditions. This thesis reports an experimental and analytical study by using finite element software ANSYS on the flexural behaviour of I–section beams made of GFRP profiles. Tests were first carried out on coupon specimens, in order to determine the material properties of the GFRP specimens used in experimental investigation. Full scale tests were then conducted on simply supported beams with span 800 mm subjected to transverse load at the top flange mid-point. The first part of the paper is aimed at investigating the flexural behavior under service and failure conditions experimentally, the objective of the second part is to study the analytical behavior of the flexural members by simulating the finite element model of the beams using SHELL element in ANSYS. The results obtained confirm that, due to the low Young’s modulus and high strength, the beam structural integrity is often governed by excessive deformation criteria or local and global buckling criteria.