Shrinkage cracks are caused by thermal expansion and contraction of the concrete.

Shrinkage cracks are caused by thermal expansion and contraction of the concrete.

• A. False
• B. True
• C. Not Applicable
• D. Both

Answer: (A)

Shrinkage cracks happen because the concrete loses moisture as it dries, causing the cement paste to shrink and create tensile stresses that crack the material when restrained. Temperature-related movements—expansion when hot and contraction when cold—cause a different type of cracking (thermal cracking) that arises from restrained expansion or contraction, not from drying shrinkage. So the statement is false: shrinkage cracks are not caused by thermal expansion and contraction. They’re mainly from moisture loss during curing and drying, with possible contributions from plastic or autogenous shrinkage, rather than temperature changes.

Shrinkage cracks happen because the concrete loses moisture as it dries, causing the cement paste to shrink and create tensile stresses that crack the material when restrained. Temperature-related movements—expansion when hot and contraction when cold—cause a different type of cracking (thermal cracking) that arises from restrained expansion or contraction, not from drying shrinkage. So the statement is false: shrinkage cracks are not caused by thermal expansion and contraction. They’re mainly from moisture loss during curing and drying, with possible contributions from plastic or autogenous shrinkage, rather than temperature changes.