building failure in UK 1

[Alistair_Heaton]

Balcony's came off.

linked to this news source as it has some decent sized pictures.

https://www.sussexexpress.co.uk/new...k-saw-my-car-crushed-under-the-rubble-4440125

Relatively new development.

 

[LittleInch]

Looks a very ropy design.

Thin flat cantilever slab with brick sides. Some level of static load there.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Sym P. le]

Random balcony departs structure disturbing the one beneath. Neither survive. Note to residents ...

 

[Alistair_Heaton]

There has to be something missing when they were building it.

 

[LittleInch]

Depends if it was designed to hold that weight of bricks or if they changed it at some point.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[LittleInch]

I reckon there was 1.5 tonnes of bricks on that weedy 100mm concrete slab with not much rebar by the look of it

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[spsalso]

The balconies were cantilevered. I surely don't see why, since the tie-back could have been inside the brick walls of the balcony.

The balconies in my dorm in college were cantilevered (concrete building). When a whole mob of my fellow dorm mates went out there, I felt it wise not to join them.



spsalso

 

[JAE]

...with not much rebar by the look of it

I don't see any bars extending out of the building, nor out of the slabs that fell.
It could be that there was a construction joint right at the exterior building line that
rusted away the bars all along that discreet line, but ALL of them at the same rate/time such that none are sticking out?

 

[dik]

I wonder what is holding the other three in place?

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

-Dik

 

[spsalso]

Perhaps structural mortar?

Note that this building is about 500' from the very ocean whose salty air was suggested to have been a cause of the failure of Champlain Towers South.


spsalso

 

[hokie66]

I can see three weedy little bars projecting from the building at the right edge, and some black dots in the slab edge, about mid-depth. Little in the way of design and construction supervision, I suspect.

 

[LittleInch]

Or insufficient overlap of bars?

It's the weight of all thoss bricks that gets me. Plus it's very likely to ba a construction joint there as well.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[dik]

It's an easy design problem... if done properly.

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

-Dik

 

[Tomfh]

The weight of the bricks obviously contributed, however heavy brick balustrades on cantilever balconies are very common. The issue here is the defective slab, in particular what appears to be defective reinforcement detailing, which failed in a brittle manner, not the fact it's carrying some bricks.

 

[JAE]

OK - so I stand corrected - a few bars are sticking out. Missed those when I glanced at the photos quick.

 

[TugboatEng]

Salt may not be necessary. This one was caused by enclosing the underside of the balcony. Without the ability to drain, moisture collected and caused the wooden structure to rot.

https://en.m.wikipedia.org/wiki/Berkeley_balcony_collapse

 

[bugbus]

Some rust staining in a few of these photos. This looks like a combination of one or all of the following: corrosion due to poor waterproofing; anchorage failure of the cantilever bars possibly due to corrosion or poor detailing; overall insufficient reinforcement.

The upper slab in Tomfh's photo looks like it has no remaining reinforcement sticking out whatsoever, as though what few balcony bars were there in the first place have just pulled straight out.

The lower slab looks like it has split in half. Is this an anchorage failure of the cantilever bars? Or possibly a secondary effect of the balcony yanking downward on the protruding bars as it fell?

 

[Murph 9000]

I feel obliged to post this:

Clarke and Dawe - The Front Fell Off

 

[Alistair_Heaton]

To be fair the lower one had every right to fail if the upper one fell onto it, even if there was nothing wrong with it.

 

[Tomfh]

The lower slab looks like it has split in half. Is this an anchorage failure of the cantilever bars? Or possibly a secondary effect of the balcony yanking downward on the protruding bars as it fell?

That's my reading of it. Those bars started peeling off the bottom of the slab, prior to breaking.