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Brian Thomas
07-24-2008, 11:29 AM
Anyone know what those little star shaped brackets are on brick buildings? I was taking a walk around an older neighborhood here today and saw several old masonry houses with little star shaped brackets on the outside wall between 1st and 2nd floor. At first i thought they were decorative but then figured they must serve some kind of purpose considering they were located in middle of the wall on every house.

Is it something that ties the floors to the wall? Anyone know?

John Arnold
07-24-2008, 11:31 AM
They are usually holding the brick wall in - evidence of structural problems. Very common here in Philadelphia.

David Banks
07-24-2008, 11:59 AM
I do not think they are necessarily evidence of structural problems. The building may have been built like that. They are usually connected to Iron rod maybe with turnbuckle for tension. Similar purpose as ceiling joist.

Brian Thomas
07-24-2008, 12:14 PM
I do not think they are necessarily evidence of structural problems. The building may have been built like that. They are usually connected to Iron rod maybe with turnbuckle for tension. Similar purpose as ceiling joist.

Yeah It seems to me that they were probably built like that. It didnt look like something that was added years later.

John Arnold
07-24-2008, 12:18 PM
I do not think they are necessarily evidence of structural problems. The building may have been built like that. They are usually connected to Iron rod maybe with turnbuckle for tension. Similar purpose as ceiling joist.
Most of the ones I see appear to have been added later, i.e, they are not centered, not lined up well, etc. And often the wall is bulging outward right where the star is.

Bruce Breedlove
07-24-2008, 12:56 PM
In areas prone to earthquakes those devices are added to protect unreinforced masonry structures in the event of an earthquake.

Markus Keller
07-24-2008, 01:21 PM
Fairly common around here in older 2-4 flat brick buildings built in the late 20's, early 30's. As someone else mentioned, they are tied to steel rods that go through to the other side with a turnbuckle somewhere along the length.
My old 2 flat had 2 on the second floor and below parapet.

Brian Thomas
07-24-2008, 01:26 PM
In areas prone to earthquakes those devices are added to protect unreinforced masonry structures in the event of an earthquake.


I am in clevelend which is as about as tectonically inactive as any place on earth so Im doubtful that is the reason they are there.

The other theory about the steel rods tying the structure together sounds pretty plausible

Jerry Peck
07-24-2008, 01:59 PM
The other theory about the steel rods tying the structure together sounds pretty plausible

That's the reason they are there, to provide tension pulling the walls together. Typically they run from one wall, through the building, to the opposite wall.

The reason for the reason they are there, though, could be "any of the above" reasons given.

All the ones I've seen 'were added after the fact' to hold things together when the structures moved and began separating.

That does not mean, however, that some were not designed with them originally.

Original or added? Depends.

Regardless, though, the reason they are there is the same - to hold things together under tension. Think of it as primitive post-tensioning. ;)

Scott Patterson
07-24-2008, 02:00 PM
I am in clevelend which is as about as tectonically inactive as any place on earth so Im doubtful that is the reason they are there.


Ahh, you might want to rethink that! :D
Map Centered at 42°N, 80°W (http://earthquake.usgs.gov/eqcenter/recenteqsus/Maps/US10/37.47.-85.-75.php)

Brian Thomas
07-24-2008, 02:08 PM
Ahh, you might want to rethink that! :D
Map Centered at 42°N, 80°W (http://earthquake.usgs.gov/eqcenter/recenteqsus/Maps/US10/37.47.-85.-75.php)

I knew someone was gonna mention that. ha ha This area gets very,very minor quakes from time to time but I have yet to ever feel one. If I cant even feel it, its not likely to send a masonry structure toppling to the ground :)

Brian Thomas
07-24-2008, 02:09 PM
Think of it as primitive post-tensioning. ;)

Speaking of post tensioning...any one ever heard of anyone drilling into a post tension concrete slab and cut one of the cables? I have heard it can cause some serious problems

Bruce Breedlove
07-24-2008, 02:23 PM
Speaking of post tensioning...any one ever heard of anyone drilling into a post tension concrete slab and cut one of the cables? I have heard it can cause some serious problems

It's true.

Jerry Peck
07-24-2008, 02:24 PM
Speaking of post tensioning...any one ever heard of anyone drilling into a post tension concrete slab and cut one of the cables? I have heard it can cause some serious problems

Very serious problems, and is very costly to repair too.

Rick Hurst
07-24-2008, 03:00 PM
I haven't drilled into and broke a post-tension cable but I've hung up a many drilled bits onto the sides of them doing termite work.

Several bits I've had to take a cutting torch and cut them off at the edge of the foundation. $150. bits used for extra reinforcement you might say.

rick

Eric Barker
07-25-2008, 09:23 AM
You can only expect so much from star anchors.

JB Thompson
07-25-2008, 11:32 AM
Anyone know what those little star shaped brackets are on brick buildings? I was taking a walk around an older neighborhood here today and saw several old masonry houses with little star shaped brackets on the outside wall between 1st and 2nd floor. At first i thought they were decorative but then figured they must serve some kind of purpose considering they were located in middle of the wall on every house.

Is it something that ties the floors to the wall? Anyone know?

I used to know their exact names. Dang, this is going to bother me.

But basically everything already mentioned is correct. They are normally used, as Jerry said, after the fact in "ordinary construction" [Type III] to tie the front and rear masonry walls from falling outward. I have seen them on the sides of buildings (at the end of a row). They're very, very common in old Texas town squares and since we don't have many earthquakes (Scott, don't send an earthquake link), I've always assumed they are just there to keep the wall from falling on me as I look up them. I've seen all sorts of shapes (hearts, moons, circles, S, stars, diamonds and lucky clovers -- oh wait, that's a breakfast cereal):D

Being a plethora of useless info, anyone else need something while I've got my brain fired up?

Bruce

oh, I remember... "spreader plate"!! Yes, I can take a nap now. woo hoo