Defects in concrete 

In this article we discussed different types of defects which occurs in concrete like 

• cracks
• crazing
• sulphate deteriorations
• effloresence
• seggregation
• bleeding 
• laitance

 Cracks 

Cracks in concrete may originate from one or more of the following reasons

Cracks in concrete

• Early loss of water
• Alkali aggregate reaction 
• Freezing and thawing
• Corrosion in steel
• Development of cracks reduces load carrying capacity of concrete 

 Crazing 

crazing of concrete

crazing of concrete results due to  difference in shrinkage between surface and interior 

The cracks rarely exceed 12mm therefore are not serious apart from the unsightness  

Sulphate deterioration 

sulphate attack is mainly caused by soil containing excess of sulphate or by sulphate water 

 Efflorescence

 Efflorescence of concrete

It is the appearance of fluffy white patches on the surface of concrete 

It is caused by poorly washed aggregates salty water used in formation of concrete 

Segregation 

segregation of concrete

Sepration or setting of coarse aggregate from mix is known as segregation

Bleeding

 separation of water from the mix is known as bleeding 

Laitance 

It is defined as water cement slurry coming out on the top of concrete surface and setting over it 

It reduces the strength between two successive lift of concrete