Structural Advice - Brick cracks near wall opening

[Sumsayso]

Greetings Structural Community. I was called in by a client to look at this unreinforced masonry structure that is showing significant cracking on both sides of an opening. The brick is three-courses deep and the cracks go all the way through the masonry wall on both sides of the opening. The opening is about 8' wide and the brick wall is about 13' tall. The wood along the top of the opening appears to be architectural only - I do not believe there is a structural header installed. My initial thought was to fill the cracks with mortar and then revisit the issue one year later to see if the cracks have worsened, but now I'm leaning towards playing it safe and recommending a steel header, steel posts, and new concrete footing under the opening to mitigate against failure of the opening.

I believe the unreinforced masonry building was originally constructed about 80-90 years ago. I'm not sure when the penetration was cut through the wall. The foundations around the perimeter of the building are concrete but I couldn't see the foundation under this wall.

I would greatly appreciate any thoughts and feedback the community has regarding this condition.

Thanks,

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1715747461/tips/IMG_9410_zuk8vf.heic
[/url][URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1715747468/tips/IMG_9409_dvnsgp.heic[/url]
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1715750572/tips/IMG_9407_so1uou.heic[/url]

 

[dik]

We need a lot more information, for example: You say the structure is 3 wythes thick. What is the brick wall construction? What is the mortar? What was the weather like during construction? What is the foundation? What is the soil? How old is the construction?
Are there any 'returns' in the wall construcion? How long is the wall? Are there any control joints constructed in the wall? Are there any close to the opening? How is the wall reinforced? How is the opening reinforced? And there are likely other questions...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[phamENG]

Hard to tell without being there, of course, but it certainly looks like a problem. It appears as though the pier next to the opening is failing. Looks like bricks are shifting and is that crushed mortar on the ground? If so, that would explain the shape of the crack on the other side of the opening.

Replacing with steel isn't necessarily the answer. It might be, but a repair in kind would probably work. You'll have to look at the whole structure to figure out the best way to go about.

I will say, though, that if it is what it looks like from this very inadequate information (to make a determination, I mean), then you need to get some shoring in there ASAP.

 

[dik]

Thanks pham... I couldn't open the files...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[ChorasDen]

It's a good idea to convert heic to jpg before posting a link, but it's even better to attach images inline.

I have nothing to add to this discussion, no experience with brick, just wanted to provide the photos in a better format.

 

[dik]

I need more information... workmanship appears to be terrible.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[JAE]

Older brick used softer mortar. Before filling in old brick with Type S mortar (hard) I'd test/sample the existing mortar and try to match its properties before doing anything.

The vertical cracks extending UP from an opening corner, and being vertical like that, suggests possible causes:
1. Wall stresses due to winds or other loads perpendicular to the wall (i.e. back and forth due to positive and then negative pressure).
2. Possible discreet foundation settlement on one side of the opening - causing a global rotation of that portion of wall resulting in a crack....although most foundation settlements under brick walls results in diagonal cracking.
3. Possible long term (years) of thermal movements where the wall shrinkage is resisted by other walls, etc.

I like option 2 - if you look at the cracking it appears that the crack gets wider toward the top, which suggests some type of rotation.

You could test/sample and match the mortar and fill in the cracks - set survey pins in the wall and monitor over time.

I don't see any cracking or serious distress BELOW the opening header so not sure that there is necessarily a need for shoring at this point -

But disclaimer - all the above based on three limited photos. Take these words accordingly.

 

[dik]

Are those floor joists in the wall, without a 'firecut'?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[phamENG]

JAE, what do you make of the apparent movement in the bricks of what I assume is the right hand jamb of the opening?

Mortar loss could be enough to cause it to drop and open that crack. The larger width up top tapering down suggests a rotation of the brick above the opening.

 

[JAE]

I just see the crack opening up wider as you go up. I don't see any vertical differential in the horizontal mortar joints - but again that's based on a photo from down below.
I tried to zoom in on it a bit and it only shows opening-type separation to me - not vertical movement.

 

[sbisteel]

That whole thing really screams "retrofit opening in existing masonry wall with insufficient lintel".

 

[dik]

The crack width appears to be fairly uniform from top to bottom; maybe cause is something other than flexure?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[phamENG]

11 courses above the duct, it's a good 1/2" to 3/4" wide. 6 (or so) courses below the duct, it's closed up again. Duct is about 4 courses tall. I'd hardly call that uniform width. JAE blew up the portion above the duct but didn't include the portion below it.

 

[JAE]

phamENG - correct - the blow-up I posted was only an attempt to see if the horizontal mortar joints vertically offset on either side of the crack.

 

[phamENG]

No criticism intended, JAE. Just pointing out to dik that the whole picture shows something a bit different.

I'm not surprised there's not a significant vertical offset there. It's only rotating about half a degree. Half a degree over 52-ish inches is about 1/2 of spread at the top of the crack. Any vertical offset would be imperceptible even at a close distance. I think the vertical offset is occurring on the opposite side of the opening. If you look at the first photo that ChorasDen converted over and posted in-line, that pier looks rough. I'm assuming, of course, that that is the pier at the opposite side. I could be off in my estimation. We don't have a good overall view. Also, the OP seems to have abandoned the thread.