Which condition would cause crazing (superficial cracking) on the surface of concrete?

Which condition would cause crazing (superficial cracking) on the surface of concrete?

• A. early curing
• B. lack of control joints
• C. too much cement in the mix
• D. early drying due to late curing or excessive water on surface

Answer: (D)

Crazing happens when the surface of concrete dries and shrinks faster than the interior can, creating tensile stresses in the thin outer layer that lead to fine, superficial cracks. This is most likely when curing is delayed or the surface is kept too wet, causing the surface to dry out early or evaporate moisture rapidly. That rapid surface shrinkage, while the interior remains hydrated, produces the network of tiny cracks typical of crazing. Early curing would help keep moisture in and reduce this effect. Lack of control joints tends to cause larger cracks from restrained shrinkage, not the fine surface cracking described. Too much cement can increase shrinkage overall, but the defining factor for crazing is the surface drying pattern, not just cement content.

Crazing happens when the surface of concrete dries and shrinks faster than the interior can, creating tensile stresses in the thin outer layer that lead to fine, superficial cracks. This is most likely when curing is delayed or the surface is kept too wet, causing the surface to dry out early or evaporate moisture rapidly. That rapid surface shrinkage, while the interior remains hydrated, produces the network of tiny cracks typical of crazing.

Early curing would help keep moisture in and reduce this effect. Lack of control joints tends to cause larger cracks from restrained shrinkage, not the fine surface cracking described. Too much cement can increase shrinkage overall, but the defining factor for crazing is the surface drying pattern, not just cement content.