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Early slab deformation

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ANSWER:
 
Isn't it so that when concrete is still soft, that it is more deformable
or has larger elongation? If so, a loss of shape at this stage should have no consequence.
 
Many years ago I read a story about a Russian plane that has a wrinkled, irregular nose part.
As it turned out, the drawings were damaged.
They elected to build it this way, because there was a death penalty for destroying state property (drawings).
 
Gregory from Oz
 
 
 
QUESTION:
 
 
From: "Thor Tandy" <vicpeng(--nospam--at)telus.net>
To: "SEAInt" <seaint(--nospam--at)seaint.org>
Subject: RE: Slab Stripped before time ...

Corrected typos

 

Interesting question .

 

I have been asked to do a structural review of an existing residence that
has a significant area of the footprint a suspended slab on circular
columns.

 

I understand that the slab formwork was stripped before the slab had
completely cured . yes there is a noticeable trough in the main part of the
slab.

 

It is a 6"+/- slab and the two-way span is approximately 15ft and the main
deformation is probably about 2".  Built in 1990 the original owner, who is
now selling, accepted the flaw.  There has been no
perceived/recorded/admitted problem since.

 

In general the construction looks good and, except for some spalling of
columns due to bits of tie-wire at the surfaces, appears sound.  The
formwork was sonatube and although I have to get the original construction
dwgs but I assume the reinforcing was tied steel cages.

 

My questions: 

 

1)      Does anyone know of literature on, or record of, impact on the
strength and/or serviceability of slabs that have deformed during the
curing/strength-gain period?

2)      Although the spalling appears localized to the tie-wire locations,
there is number of them.  Could this also be a sign of deeper issues?  I.e.
would the tie-wire spalling open up access to the stirrups etc in the
column?