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What is cracked concrete?

Posted by Zachary VanLemmerenover 7 years ago
What is cracked concrete?

Can you explain to me what the term cracked concrete means?

ACI,Cracked concrete

1 Reply
Posted by Aidanover 7 years ago
Hilti Verified

Hi Customer,

well this is a good question. Concrete is typically assumed to crack under normal service load conditions or, more specifically, when tensile stresses imposed by loads or restraint conditions exceed its tensile strength. Crack width and distribution are generally controlled through the use of reinforcement. With consideration for the protection of the reinforcing steel, crack widths, per ACI 318, are assumed to be less than approximately 0.012 in (0.3 mm). Under seismic loading, flexural crack widths corresponding to the onset of reinforcing yield are assumed to be approximately 1-1/2 x static crack width = 0.02” (0.5 mm).

Both ACI 318 and the International Building Code conservatively assume cracked concrete as the baseline condition for the design of cast-in-place and post-installed anchors since the existence of cracks in the vicinity of the anchor can result in a reduced ultimate load capacity and increased displacement at ultimate load compared to uncracked concrete conditions. I hope I have answered your question. If there is anything else, please let me know.

All the best
Aidan