Tilt-up wall panel - bowing

[sundancekid]

I have a problem with a panel bowing -- possibly due to solar heat gain in the late afternoon. This problem is most apparent at the corner where this panel is the “long” panel at the corner and it meets the straight edge of the “short” corner panel.

Facts:
Location – Atlanta, GA
Age of structure – 3 years
Wall exposure – west north west
Wall ht – 34’ AFF and 4’ dock ht.
Wall finish – exposed concrete with arch. form liner finish
Amount of permanent bow – bottom 0”, mid-point ½”+, top 0” (this has progressed over time)
Panel thickness – 9” total (8-1/4” if you deduct for arch. form liner)
Interior use – warehouse – heat only
Roof load – nominal (barjoists run parallel to wall)
Misc. Note – there is a corner crack that is apparent from the interior only across the bottom corner (6 feet) of this panel (it does not seem to be moving or to be contributing to the bowing issue)

Over the last three years the ½” plus bow in this panel has become permanent and I have the following questions:

Q1- is there some other potential problem besides thermal gain that I should be looking at?
Q2- Do you have any ideas that I can pass on to our structural engineer on how to fix this problem?
Q3- Will this wall continue to bow out more & more with time?

 

[DTGT2002]

Were measurements done early on that show the wall at it's original location? Was there an initial difference? My line of thinking is that the wall may not really be bowed, it may have been formed that way. Does the same difference show up on the outside of the wall?

Good luck,

Daniel

 

[sundancekid]

There was no initial difference. As matter of fact there is a security camera system mounted abount 3/4 ths up on the wall. The mounting system wrapped the corner and was anchor bolted in both direction. The bolts resisting this bow have failed in shear.

 

[dik]

Several questions (not enough info to try to determine what's causing it):

does the 1/2 bow fluctuate during the day? The northwest corner is likely the least affected by thermal activity.

Is there a problem with other components? at other corners where the thermal effect may be greater?

How is the panel anchored? or supported? Is it a fairly rigid connection? Are any of the supports moving? horizontally?

Is there any eccentric loading? Roof load is small from OWSJ; is there a beam?

Did the failure of the camera connection give rise to noticing that the corner had moved?

How large are the panels? Is there any sort of expansion joint between adjacent panels?

Was the panel cast 'flat' during initial installation?

Is there a humidity problem that may cause 'curling'?

Just for a start...