What is curing and its importance? | Q & A

What Is Curing?

Curing is the process of maintaining adequate moisture and temperature in concrete after placing, so that cement hydration continues and the concrete attains its required strength and durability.

Why Is Curing Important? (Importance)

Proper curing is critical for the following reasons:

1. Strength Development

• Cement gains strength only in the presence of water

• Poor curing can reduce strength by 30–40%

2. Durability Improvement

• Reduces permeability

• Increases resistance to:

  • Weathering

  • Chemical attack

  • Corrosion of reinforcement

3. Crack Control

• Prevents plastic shrinkage and drying shrinkage cracks

• Keeps surface moist during early age

4. Surface Hardness & Finish

• Improves abrasion resistance

• Prevents dusting and surface scaling

5. Volume Stability

• Ensures uniform hydration

• Reduces differential shrinkage

When Is Curing Started?

• After initial setting of concrete

• Typically 8–12 hours after concreting (depending on weather)

Minimum Curing Period (As per IS 456)

• OPC: Minimum 7 days

• Blended cement (PPC/PSC): Minimum 10 days

• Hot/dry weather: Longer curing recommended

Common Methods of Curing

• Ponding (slabs)

• Sprinkling / wet hessian

• Covering with plastic sheets

• Curing compounds (where water is scarce)

One-Line Interview Answer (Perfect)

Curing is the process of maintaining moisture and temperature in concrete after placing to ensure proper hydration, strength development, durability, and crack control.

Common Interview Follow-Up Questions

Q: What happens if curing is not done properly?
A: Reduced strength, increased cracking, and poor durability.

Q: Which curing method is best for slabs?
A: Ponding or continuous sprinkling.

Site Tip for Fresh Engineers

Never stop curing early because:

• Cube strength looks OK

• Client pressure

Concrete gains strength over time, not overnight.