Abstract: Fracture energy is an important technical specification to evaluate the anti-cracking capacity of glass fiber reinforced cement (GRC). The effects of glassfibre length and content, water-to-binder ratio and sand-to-binder ratio on the fracture energy of GRC produced by premixed casting were studied through experiments. The results show that glassfibre significantly improves the fracture energy of cement-based materials. When the glassfibre content does not exceed 3% of the solid component mass, the fracture energy of GRC increases greatly with the increase of glassfibre content, which is approximately linear. When the glassfibre content is constant, the fracture energy of GRC increases first and then decreases with the increase of glassfibre length. When the glassfibre length is 20mm, GRC has higher fracture energy. The fracture energy of GRC is mainly derived from the extraction energy of glassfibre. Both the water-to-binder ratio and the sand-to-binder ratio have a significant effect on the extraction energy of glassfibre. The increase of water-to-binder ratio will reduce the flexural strength of GRC, but the fracture energy of the GRC increases significantly with increasing water-to-binder ratio. The water-to-binder ratio increased from 0.32 to 0.50, and the fracture energy of GRC increased by 227%. The fracture energy of GRC decreases with the increase of sand-to-binder ratio.

Key words: glass fibre-reinforced cement, fracture energy, premixed casting method, water-to-binder ratio, sand-to-binder ratio