Durability of glass fiber reinforced cement composites: Effect of silica fume and metakaolin

The primary concern for glass fiber reinforced cement composites (GFRC) is the durability of glass fibers in the alkaline environment of cement. Despite the use of improved alkaline-resistant glass fibers (AR-glass) and pozzolanic materials such as silica fume and fly ash, durability concerns still exist. This report presents an experimental investigation on the hot-water durability of glass fiber reinforced cement composites. Hot-water durabilities of AR-glass fiber reinforced composites in blended cement matrix were compared for their flexural and tensile performance. The different matrices selected were (a) cement; (b) cement + 25% metakaolin; and (c) cement + 25% silica fume. Specimens after normal curing of 28 days were immersed in a hot wafer bath at 50 degrees C for up to 84 days and then tested in flexure and tension. The results indicate that the blended cement consisting of synthetic pozzolan metakaolin significantly improves the durability of GFRC composite. (C) 1997 Elsevier Science Ltd.