Technical Data Sheet


Technical Data Sheet for Geopolymeric cement type (Potassium, Calcium) – Poly(sialate-siloxo) / (K,Ca) – (Si-O-Al-O-Si-O-), Si:Al=2:1

Further details in Davidovits’ book, GEOPOLYMER Chemistry & Applications, Part III, Properties, Chapters 15 to 18, GEOCISTEM , GLOBAL WARMING, and also previous papers in the Geopolymer Library.

Tested on standard sand mortar prisms:

  • setting: 10 hours at -20°C to 7-60 minutes at +20°C.
  • shrinkage during setting: <0,05%, not measurable.
  • compressive strength (uniaxial): > 90 MPa at 28 days (for high early strength formulation, 20 MPa after 4 hours).
  • flexural strength: 10-15 MPa at 28 days (for high early strength 10 MPa after 24 hours).
  • Young Modulus: > 2 GPa.
  • freeze-thaw: mass loss < 0,1% (ASTM 4842), strength loss < 5% after 180 cycles.
  • wet-dry: mass loss < 0,1% (ASTM 4843).
  • pH: crushed and powdered, 11-11,5 after 5 minutes in deionized water (compared to Portland cement: 12 to 12,5, and granite: 11).
  • leaching in water, after 180 days: K2O < 0,015%.
  • water absorption: < 3%, not related to permeability.
  • hydraulic permeability: 10-10 m/s.
  • Sulfuric acid, 10%: mass loss 0,1% per day.
  • chlorhydric acid 5%: mass loss 1% per day.
  • KOH 50%: mass loss 0,02% per day.
  • ammoniac solution: no mass loss.
  • sulfate solution: shrinkage 0,02% at 28 days.
  • alkali-aggregate reaction: no expansion after 250 days, -0,01% (compared to Portland Cement with 1% Na2O, +1,5%).
  • linear expansion: < 5.10-6/K.
  • heat conductivity: 0,2 to 0,4 W/Km.
  • specific heat: 0,7 to 1,0 kJ/kg.
  • electrical conductivity: strongly dependent on humidity.
  • thermal stability:
    • mass loss < 5% up to 1000°C.
    • strength loss < 20% at 600°C, < 60% at 1000°C

Other values:

  • D.T.A.: endothermic at 250°C (zeolitic water).
  • MAS-NMR spectroscopy:
    • 29Si: SiQ4, major resonance at -94,5 ± 3ppm.
    • 27Al: AlQ(4Si), major narrow resonance at 55 ± 3ppm.
  • Energy consumption: SEC for cement 1230-1310 MJ/tonne (compared to Portland clinker 3500 MJ/tonne).
  • CO2 emission during manufacture: 0,180 t/tonne of cement (compared to Portland clinker 1,0 t/tonne).