ABSTRACT
Introduction Composite materials such as the glass-fibre reinforced materials GRP (glass-fibre reinforced polyester), GRC (glass-fibre reinforced cement) and GRG (glass-fibre reinforced gypsum) rely for their utility upon the advantageous combination of the disparate physical properties associated with the individual component materials. This is possible when a strong bond between the glass fibres and the matrix material ensures that the two materials within the composite act in unison. Thus polyester, which alone has a very low modulus of elasticity, when reinforced with glass fibres produces a material which is rigid enough for use as a cladding material. Cement, which alone would be brittle, when reinforced with glass fibres can be manufactured into thin impact-resistant sheets. Similarly glass-fibre reinforcement in gypsum considerably increases its impact and fire resistance.
