Glass fibre reinforced concrete - Low alkali calcium sulfo-aluminate cement which developed by Chinese expert is special cement for GRC products. The clinker’s main mineral composition in is C4A3S, C2S and iron phase.
Technical data:
Specific surface area (M2/kg):≥ | 400 |
Setting time(min): | |
Initial setting time | ≥ | 25 |
Final setting time | ≤ | 180 |
(The setting time can be adjusted according to client’s request) |
Alkalinity: In cement slurry of water cement ratio 1:10, one hour’s PH value≤10.5
Free expansive rate: 1:0.5 cement sand ratio. The free expansive rate of 28 days is 0.00%~0.15%;
Strength of each age should not less than the value in following table:
1day: 32MPA
7day 42.5MPA
Characteristic:
Low alkali calcium sulfo-aluminate cement has the merit of early strength, low alkali, short stationary phase, small dry shrinkage rate. Glass fiber has high strength retaining ratio and longer work-time when work with low Alkali calcium sulfo-aluminate cement. So it is the special cement for making GRC products. The GRC’s life can reach 100 years when use with alkali resistant glass fiber produced by Chinese.
Comparison with modified Ordinary Portland Cement
The comparison of testing result of thermal aging models under 80°C hot water between the GRC that made of low alkali calcium sulfo-aluminate cement and Cem-Fil-2 or NEG Alkali resistant glass and GRC that made of modified ordinary Portland Cement and Cem-Fil-2 or NEG Alkali resistant glass is: during the thermal aging period, GRC with low alkali calcium sulfo-aluminate cement’s three days ultimate bending strength is decreased but 7 days bending strength is basically same and 28 days ultimate bending strength is 20.7% higher than GRC with modified ordinary Portland cement, and it keep good deformation property.
