Engineering Materials·MCQ explained

Membrane curing of concrete is done by:

Try it first: pick an option, then read the explanation.

Correct answer: D. Applying paraffin or resin-based liquids on the surface

Detailed Explanation: Membrane Curing — Chemical Sealing of the Surface

Why D (paraffin or resin-based liquids) is correct: Membrane curing is a dry method of curing. Instead of adding water to the concrete surface, a waterproof liquid compound is sprayed or applied. Once it dries, it forms an impermeable membrane that traps the existing mix water inside the concrete, preventing evaporation and allowing hydration to proceed.

Membrane Curing Compounds

TypeMaterialApplication
Wax-basedParaffin wax emulsionSprayed on freshly finished surface; white or clear
Resin-basedAcrylic, styrene-butadiene resinSprayed; forms clear, UV-stable film
Bitumen-basedBitumen emulsionBrushed or sprayed; dark colour
Polyethylene sheetingPlastic filmLaid over fresh concrete; sealed at edges

All Curing Methods Classified

CategoryMethodPrinciple
Wet curingPondingAdds water continuously
Spraying / foggingAdds water intermittently
Wet cloth / hessianKeeps surface moist
Membrane curing (dry)Paraffin / resin compoundSeals surface; prevents moisture loss
Plastic sheetingPhysical barrier against evaporation
Accelerated curingSteam curingElevated temperature + moisture; for precast
  • Membrane curing = applying paraffin or resin-based liquids to seal the concrete surface.
  • No external water added; existing mix water is retained for hydration.
  • Ideal for large flat areas (roads, airfields) where wet methods are impractical.