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Masonry wall affected by weather and humidity

Masonry wall affected by weather and humidity

Masonry wall affected by weather and humidity

(OP)
We just erected a Masonry load bearing structure in NYC this past winter.
The structure is a two story building with a cellar and a basement. The perimeter and interior center walls are 8" load bearing blocks supporting an 8" precast plank.

The roof could not be installed in timely manner and for couple of months (Jan/Feb)the interior middle CMU wall along with metal frames were subject to significant amount of cold water( from melted snow or rain)and low temperatures; in fact a portion of the wall in the 1st floor blow-out due to freezing conditions. (see photo)

After a recent inspection we find out that the middle block wall is out plumb and bellied above the door frame CMU bond beam lintels at several locations through the building.

The movement of the wall above door frame, could be as a result of the direct exposure to high humidity and cold weather which may expanded or contracted the block wall and/or metal frames? How can we rectify this problem?

Thanks  

RE: Masonry wall affected by weather and humidity

The photo doesn't mean much without context.  Please post a couple more photos showing more of the wall and alignment.

RE: Masonry wall affected by weather and humidity

Looks like you just invented a new way to create split-faced block.  bigsmile

Mike McCann
MMC Engineering
Motto:  KISS
Motivation:  Don't ask

RE: Masonry wall affected by weather and humidity

(OP)
Ron,

Here are several photos. The variations in the wall are difficult to detect by visual observation. The wall misalignment was detected and more obvious when the ceiling grid system started with the installation of a track against the CMU wall.

RE: Masonry wall affected by weather and humidity

Looks like some poor protection of the walls and melt water draining down into the cores. When it froze, it went wherever Mother Nature decided. That delay witout heat was a real disaster.

Humidity is not the problem, but frozen humidity in a solid form (ice) certainly is when it is confined during the freezing process.

In the first photo, there must have been a horizontal obstruction blocking the vertical core and preventing drainage to a lower area. - Could be a horizontal bond beam (I don't know why) or a some utilities coupled with a barrier of some sort.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

RE: Masonry wall affected by weather and humidity

(OP)
Dick
There is a continuous bond beam below the plank and an additional over the M.O.'s   
We are confronting the bellied at top of the wall. The north side of this particular wall (about 90Lf) bellied out +- 1" and the south side (about the same length) contracted the same on three floors.

Heat was provided for the facade erection only, changing the heating units from north to south.

Could this problem affect or develop into another major dysfunctional behavior of the structure?

Franklin

RE: Masonry wall affected by weather and humidity

Any initial deformation affects the structural capacity of the wall. The structural designer can assess the impact of it by making again the calculation with a provision for such initial imperfections (additional eccentricity if what initially accounted not enough to cover this problem) and maybe with a reduced CMU strength if thought to have been affected by exposition to freezing condition. Normally the actual impact will be scarce but at least for the long walls bracing counterfort walls or pilasters are not seen and this is not good for stability and strength.

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