Miami Beach to have emergency inspections for 500 buildings near 40 years old (Palm Beach: condo, contractor)

[Corrie22]

Originally Posted by k350

The building sits on dozens of support posts, they drilled deep into the bedrock, drop a rebar cage, then fill with concrete, that is how these buildings are built.

Those piles were pre-formed and driven...see the numbers on them...if you try to site pour in sand...you have to form or the sand fills back in

Originally Posted by cjseliga

I was wondering how deep the bedrock is along the coast of Florida.

...about 30 ft where that bldg sits

[forzalugano]

Reinforced concrete hides a potential flawm the same corrosion-prone steel reinforcement rebar that makes it stronger. Rusting rebar loses its bond with the surrounding concrete and creates iron oxide, which expands, resulting in tensile stressesand eventual deterioration. Concrete’s natural alkalinity reduces rebar corrosion, protection was needed for reinforced concrete exposed to the Miami seawater and large quantities of deicing salt from hurricans etc.

I would only buy a buidling on the sand like that will all steel been framing welded together into one solid structure.

[beach43ofus]

Originally Posted by Huasho

Lot's of Job Openings I see.

Don't ever let a calamity go to waste, as they say.

[k350]

Originally Posted by Corrie22

Those piles were pre-formed and driven...see the numbers on them...if you try to site pour in sand...you have to form or the sand fills back in




...about 30 ft where that bldg sits

Either preformed or poured, all the same. We use to use sleeves for several feet until we cleared the sand and hit the clay. But point was it is not sitting on the sand like a slab foundation like some people seem to think it is.

[Travelassie]

Originally Posted by SanyBelle

I usually agree with you, Travelassie. But can you tell me exactly how many buildings in Florida or in the US have suffered the same fate in the last 100 years?

Fortunately, up to this point, I haven't heard of any. But there have been any number of complaints about water intrusions onto the properties, into parking garages and ground level structures of beachfront condos, other buildings. These generally occur in conjunction with high tides (especially king tides and similar phenomena), storms and are blamed by the "climate change" activists by rising seas, though at the land elevations and nature of the land where the buildings are located, ( sea level, "land" reclaimed from Biscayne Bay by dredging and fill), IMO it's not hard to imagine mother nature reclaiming her own over the decades.



I imagine that water intrusion into structures built on that "land" would be a frequent event. That area, and much of Miami Beach was virtually a sandbar before the dredging to change it into "buildable" land took place in the early 1900's, IIRC.



What I have seen, at least on the west coast of Florida ( where I'm now located), is serious beach erosion that gets dangerously close to beachfront buildings, even in two cases where I've seen undermining of the parking garages under the buildings. At one location the concrete floor of the building buckled, broke up, and the pilings looked compromised- they moved the parking at first, then as the process continued they had to close the buildings ( this was a vacation resort, not a permanent residence, so it didn't involve uprooting residents) and make repairs.



But such undermining by water over time may well, as I see it, compromise not just the bottom floors but if they're damaged ( as we saw in the vacation resort), other parts of the structure would be stressed as well, if nothing else from the loss of the structural integrity of the "pieces" below or around them. (Not a structural engineer here, by any stretch, so I don't know how to best express it). I know pilings are driven well below the surface to support these buildings, but its also possible that these fail over time from erosion, wave action or just weathering. Or possibly shortcuts or poor materials used to save money during construction.


And now, we HAVE seen one building virtually collapse in an area plagued by water intrusion, and while there may be other contributing factors to this collapse ( I'm sure these will be discovered with any investigation), it's still my opinion that building high rises on this type of land is not a good idea.

[Corrie22]

Guys, the buildings elevation was ~50 ft....that area was not plagued by water intrusion....the water intrusion was from the swimming pool and the deck around it

Miami Beach elevation map > https://en-us.topographic-map.com/ma...3/Miami-Beach/

blow the map up until you can read street numbers..go up to 88 st....there's the building

[OneDawg]

https://www.miamiherald.com/news/loc...252398053.html

[WestGuest]

The salt from the ocean also helps deteriorate these buildings, many seem to be cheap apartment conversions from the 1970's.

[Corrie22]

Here's a list of buildings on Miami Beach....from 1939 to 1941....all of them concrete...all right on the ocean...and all a whole lot older

https://en.wikipedia.org/wiki/Miami_...tural_District

====

..and a list of historic properties

https://apps.miamibeachfl.gov/histpr...r/default.aspx

[Travelassie]

Originally Posted by Corrie22

Guys, the buildings elevation was ~50 ft....that area was not plagued by water intrusion....the water intrusion was from the swimming pool and the deck around it

Miami Beach elevation map > https://en-us.topographic-map.com/ma...3/Miami-Beach/

blow the map up until you can read street numbers..go up to 88 st....there's the building

Thanks for the information. You wouldn't think at 50 feet direct intrusion by salt water from the bay would be a contributing factor, and it doesn't look as though these buildings are directly on the beach anyway. Not that this is the same thing, but I'd have to think that the effect of closeby salt water over time would corrode, rust out metal components ( rebar, other supporting components), weakening them. Guess that's why they have periodic inspections, but were the problems reportedly cited in the 2018 inspection of this building followed up?

It may not have been a factor in the collapse of this building, but I still have to question the wisdom of wall to wall building, especially of high rises, on barrier islands- essentially sandbars built up over time, enhanced by dredging when developers see another potential for the $$$$$$$$$$. Manasota Key comes to mind.