This document discusses various methods of curing concrete, including water curing, membrane curing, steam curing, and electrical curing. It notes that curing allows for continuous hydration and strength gain in concrete. Proper curing retains moisture on the surface and prevents early drying out, leading to increased strength and durability. A new technique called "drip curing" is also introduced, which can reduce water consumption during curing by up to 80% through the use of multilayer sheets that drip water onto the concrete surface.

2. CONTENT
Sr. No. Description
1. Introduction to curing
2. Importance of curing
3. Methods of curing
4. New Techniques of curing

3. What is curing ?
1
Maintenance of moisture and temperature of freshly placed concrete to ensure proper
hardening of concrete for attainment of desirable strength and durability.
“An efficient curing in the early period of hydration can be compared to a good and
wholesome feeding given to a new born baby.”
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4. Introduction
• The properties of hardened concrete, especially the durability, are greatly
influenced by curing since it has a remarkable effect on the hydration of the
cement.
• Curing allows continuous hydration of cement and consequently
continuous gain in the strength, once curing stops strength gain of the
concrete also stops.
• Proper moisture conditions are critical because the hydration of the cement
virtually ceases when the relative humidity within the capillaries drops
below 80% .
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5. Effect of W/C ratio
• Recommended higher w/c ratio about 0.5
• And if hydration is continue for a long time, then other measure ( curing )
must require to prevent the loss of moisture.
3
0.23
(hydration)
0.15
(filling gel pores)
+ =
0.38
( complete hydration of
cement )
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6. Curing period
• UNDER NORMAL WEATHER CONDITION
min 7 days – concrete made with OPC
min 10 days – concrete made with blended cement ( PPC, PSC)
• UNDER HOT WEATHER CONDITION ( TEMP. MORE THAN 40 ˚C )
min 10 days – concrete made with OPC
min 14 days – concrete made with PPC, PSC
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7. Effect of delayed curing
• Curing started after 3 days reduces,
7 day strength by 12 %
28 days strength by 10 %
• Air exposed concrete will reduce 50 % strength as compared to moist cured
concrete.
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8. What does curing do ?
• Retains moisture on the concrete surface
• Prevents loss of moisture by evaporation
• Reduces shrinkage cracks
• Increase compressive strength, improves durability, wear resistance and
water tightness
• Essential for promoting hydration
• Maintain conducive temperature.
• Needed for capillary segmentation
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9. DO’s & DONT’s
• Start curing immediate after it get sufficient hardness to take load of person
• Do not walk on freshly laid concrete for sprinkling the water
• Water fit for drinking must be used for curing
• Do curing continuously, intermittent will result in cracking
• During summer, prevent drying the surface of freshly laid concrete.
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10. Method of curing
8
Water curing
Membrane
curing
Application of
heat
Calcium
chloride
Direct
application
Wet covering
Bituminous
compounds
Clear
compounds
Water proof
papers
Steam curing
Infrared
radiation
Electrical
curing
Surface
application
Admixture in
dry form
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Admixture in
solution form

11. Water curing
Immersion Ponding
Spraying Wet covering 9curing of concrete

12. Membrane curing
Effective – In area having seasonal lacking of water
Aim – To act as a barrier between surface to atmosphere to prevent the
evaporation of moisture from concrete
BLACK COMPOUND :
- asphalt emulsion , cutbacks , coal-tar pitch etc.
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13. CLEAR COMPOUNDS :
• Generally other than black colour
• 30 % or more of blends of non volatiles
11
WATER PROOF PAPERS :
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• Papers are made of two sheets struck
together by rubber latex composition
• Satisfactory for concrete slabs and
pavements

14. • Merit :
It act as a physical barrier to prevent the loss of moisture from the
concrete to be cured.
• Demerits :
- 28 days curing with membrane = 2 week moist curing
- May not assured full hydration
- Using black compound on the exposed surface, there may be
absorption of heat resulting in cracking.
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15. STEAM CURING
• w/c ratio – 0.3 to 0.7
• Low water cement ratio
more effective steam curing
slow temperature rise
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16. • It should be suggested that steam curing should be followed by water
curing for a period of at least 7 days.
• Two types :
LOW PRESSURE STEAM CURING :
- carried out at atmospheric pressure
- concrete products are stacked in chamber ( intermittent process )
PROCEDURE :
1. Heating up stage : 10 ˚c/hr , 2 to 3 hour1
2. Steam treatment stage
3. Cooling off stage : 30 ˚c/hr , 1.5 hour
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17. • HIGH PRESSURE STEAM CURING :
- example : AUTOCLAVE
- temperature : 185 ˚ C
- time : 7 to 10 hr
ADVANTAGE :
- High early strength
- High durability
- Resistive to sulphate action and freezing and thawing
DISADVANTAGE :
- Reduces the bond strength of concrete.
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18. Electrical curing
• Concrete can be cured by passing alternating current of low voltage and
high amperage through electrodes in form of plates covering the entire area.
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19. Necessity is the Mother of
Invention
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20. • Most common methods used for curing are sprinkling water and gunny bags that
are water consuming.
• Using drip curing will reduce water consumption up to 80%
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DRIP CURING

21. • Multilayered sheets- Water pockets, Gunny bags(Jute) and PVC Films are
used.
• Filling the pockets once in a day the water will drip drown throughout the
day through the films.
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22. Why drip curing?
• Reusable
• Faster strength gain
• Eco- Friendly
• Economical
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23. 20curing of concrete

24. References
• Concrete Technology – M. L. Gambhir
• Concrete Technology – M. S. Shetty
• IS : 456 – 2000 code of practice for plain and reinforced concrete
• IS : 9013 – 1978 Method of making curing and determining compressive
strength of accelerated cured concrete test specimen
• Developing a New Curing Technique-‘Drip Curing’ - (IJRASET) by
Kanchan Ambekar, K.U. Gandhare
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25. THANK YOU