Crack width matters in transient situations?

[lpz31415]

I'm designing a wall wich requires crack width checking (spanish code). In a transient state crack width check fails, but for the final state it's ok.
Transient state duration will be maximum 2 months.

Any suggestion about how to consider this issue? As I understand, crack width should be checked at service state, once the construction works have ended.

 

[Agent666]

Guess you have to ask if it's loaded in a way that the cracking will be recoverable to some degree if & when it's unloaded from the transient loading scenario (presumably some temporary loading during construction)?

 

[IDS]

It's not a question with a simple universal answer.

You really need to look at how cracks exceeding the specified maximum width have been handled in previous cases in your locality, and by your client (if they have a public previous history available).

Other thing's to consider are:
The exposure conditions of the cracks.
The effect of shrinkage and differential temperature.
The possibility of cracks closing less than expected.

Certainly the safest approach would be to design to limit the crack width under the transient loading.

Doug Jenkins
Interactive Design Services

http://newtonexcelbach.wordpress.com/

 

[Ron]

Monitor the cracks until construction is complete and then evaluate the issue. If the cracks have widened, then inject with epoxy. If they remain the same and they are within your code...let it go.

 

[dik]

With a caveat that often repairing cracks makes them look a lot worse.

Dik