The Miami condo collapse is a reminder of America's artificial land problem
theweek.com
theweek.com
What was the problem? Local government rules stated that foundations were inspected every forty years. So the first inspection of this building was 2021 and had just begun when it collapsed.
Why not inspect building foundations every twenty years (or sooner) if significant sinking was found?
Sinking isn't always a problem - look at Venice! I studied Civ Eng at Plymouth Poly (now a university, Devon not MA) back in 1989ish. Back then concrete cancer was all the rage ... and gabions (but I digress.)
The failure of the building in Miami was catastrophic and not gradual. I don't think that monitoring would have worked but it is possible that stresses/strains built up over time - we'll have to wait and see. If it was gradual then there is a good argument in favour of fitting buildings like that with strain gauges as many bridges are. I do a lot of IoT stuff and I estimate that something like £20,000 would get you strain gauges and a monitoring system for a structure like that. It might be £10,000 or £100,000 but a building that size in Miami is worth quite a lot. I'll bet rent on a flat was something like $2,000pm or more.
Inspection of foundations is a tricky one. I am not a Civil Engineer but I trained for it but I don't have X ray eyes and nor do Miami's engineers. That's absolutely the wrong way to go about this sort of thing. I'm not even sure what an "inspection" even means.
There was a fundamental error made at the initial design stage in my opinion. I don't know what but probably relating to the parameters of the ground that was built on. By that I mean that the architects/struct engrs. were promised certain properties of the geotechnics/geophysics - that basically means they were told how the ground would work in holding their structure up.
When you design a structure, it needs to support itself and crucially, the thing it sits on needs to be able to support that structure. You also have to work to a timespan, so you use standard tables for wind strength, earthquake etc. You work to a 1 in n years events.
This building collapsed catastrophically in seconds without warning. I think this will become a real lesson for Civ Eng and not a simple "I told you so" thing and certainly not "shit concrete".
Both statements are correct, but differential settlement is not an "instantaneous" problem, when a building, particularly a reinforced concrete one, is subject to differential settlement it deforms itself following the movements of the foundations or of the soil under the foundations, and this normally allows for several centimeters of deformation (in practice a building as seen from a side is made out of squares, when the foundations on one side lower, squares become a rhomb/diamond). All the rigid elements in the plane of the square (please read as walls, be them brick or other material) are forced "out of their natural shape" and start developing cracks.
Nornally settlement is a process that is very, very slow, years, months or weeks, during which the cracks begin developing, long before the structure collapses.
This must have been a form of failure of the soil that happened in a very short time, more similar to a landslide than to the kind of settlement common in soils (usually sands) near a waterfront.
1) settlement isn't a problem,
2) differential settlement is a problem.
Both are correct, but in this case neither settlement nor differential settlement appears to be involved in the collapsing of the building.
It all happened because the builder didn't want to go 200' to hit bedrock and instead cheapened out.
[1]https://www.sfgate.com/news/editorspicks/article/SF-s-sinkin...
- Pump water out of the excavated ground. It was a slow drain, maybe 50 gallons per minute, but it ran for months.
- Drive dozens of 90 foot steel pylons into the site with an enormous pile driver.
- Pour the foundation over the pylons.
The Millenium Tower is more than double the height of that, at 46 stories, and it’s right by the water. But they used the same length of pylon. Mind-boggling.
Take a look at the Florida keys, where you can find bedrock after a couple of meters. You can even go out a mile into the sea and hit bedrock after 6-8 meters:
https://pubs.usgs.gov/pp/2007/1751/professional-paper/figure...
“Digging down in Amsterdam, it takes about 1000 meters until we find the first solid rock”.
There are more or less solid sand layers at much lower depths, though. That’s what buildings stand on.
It would surprise me if other cities in the west of the Netherlands were different.
This rock is not an ideal foundation material. http://www.mgs.md.gov/geology/geohazards/engineering_problem...
Harder rock is deep, around 1,300m. (4,000ft). https://ufdc.ufl.edu/UF00000245/00001/20x
The Caribbean is nowhere near shallow, take a look at a marine chart or just the seafloor topography on google maps. The Caribbean is thousands (often over 10K) of feet deep in most areas.
Also, this has nothing to do with hurricanes, which originate off the west coast of Africa.
Also, the Florida Keys are not in the Caribbean.
Oracle's HQ is still standing. But the (East) Palo Alto 4 Seasons Hotel, whoops.
Also, I guess that differential sinking can be detected before catastrophic failure if the sink rate were measured on two or more points on the building. If the south side is sinking at 2mm/year while the north side is sinking at 0.2mm/year, that sounds like a recipe for disaster that you don't need xray eyes to see.
This seems like simultaneously survivorship bias (there have been plenty of buildings in Venice that have collapsed or have been irreparably damaged) and a good example of the dangers of sinking (how many billions on repairs and massive engineering projects to save the city?)
Or socially, because fixing the problem was an economic non-starter for the condo association. Or a political non-starter depending on how you squint.
https://www.nbcnews.com/news/us-news/cause-miami-condo-colla...
"Another issue at hand for the Surfside community is one shared with all of Miami Beach: The towns are built on a barrier island. Climate scientists and geologists have long warned that these islands cannot be developed responsibly. They are made of a loose mixture of sand and mud and provide a natural protection for the shoreline.
'These are very dynamic features. We didn’t understand that these islands actually migrate until the 1970s,' said Orrin Pilkey, a professor emeritus of geology at Duke University who has long studied sea-level rise and the over-development of the coast. 'As sea level rises, they move back.'"
Edit: I think it is already answered in [1].
[1] https://en.wikipedia.org/wiki/Palm_Islands#Risk_mitigation
However, that doesn’t suddenly make it the governments sole responsibility.
I think “alarming” was the term used by USA Today which first reported the study. The scientist himself did not seem alarmed at all:
> Wdownski said he doesn’t believe anybody in the city or state government would have had a reason to be aware of the findings of the study. The bulk of it focused on potential flooding hazards, not engineering concerns. The study’s mention of the “12-story condominium” was relegated to a single line. “We didn’t give it too much importance,” Wdowinski said.
That's the way people are.
And there are many many miles of similar buildings owned by similar people up one side of Florida, down the other, and around the Big Bend.
Each built on sand.
Each sprayed with salt from the sea.
And every one of them built to meet code..."meets code" being the worst possible legal construction.
The only thing unusual about the building that collapsed is that it was the first.
Nope, common road vehicles have never been ideal way down on South Florida beaches, even back when there were no rules. The ATV's like the lifeguards have are the kind of thing that really works, or a dune buggy with the fat tires even in places where there were no dunes. Anything heavy just sinks more than you would want.
Because the beach there is so soft you can feel the difference as you walk, and it consists more so of particles of eroded seashells (calcium carbonate) having much larger size, much more random and irregular shapes, and a much wider particle size distribution than the far more universal and familiar true sand elsewhere.
And it all leads more steeply into the Atlantic Ocean, it's not the really wide sandy beach that sometimes is considered more desirable.
Notwithstanding any replenishment which can can upset the balance for a period compared to naturally deposited or eroded material.
The sandcastles that can be built have differences in limitations that can be felt by hand.
And IIRC the building contrators were not all of the highest integrity.
I would say my experiences exploring many of the hi-rises in nearby Broward as a teenager after-hours at the construction sites as they were being built in the late '60s & early '70s was not unique.
All kinds of kids did this in South Florida . . .
There just weren't that many kids when the bulk of the population is retired from up north.
I'm sure I could come up with a word or 2,000 on the subject or even more now after the deadly collapse.
Here’s his video on Miami’s bridge collapse in 2018:
Written about here: https://www.miaminewtimes.com/news/fiu-bridge-collapse-myste...
His video production quality is a little rough, but nonetheless his videos are quite interesting. I never knew concrete was so fascinating before coming across his channel.
To me “landfill” implies trash/refuse disposal and “artificial land” implies infill of formerly wet/low areas. Not nearly all of the latter is the former.
For example this link redirects back to the OP's URL
https://theweek.com/trump/murder/1001964/miami
I always find CMSs lazy hacks for a clean URL fascinating.
I personally put the number as close to the domain as I can get away with, because the farther away it is, the more likely it is to be truncated, and I don't care how nice the partial URL looks, if it's missing the number, I can't get your content. And no, I'm not building it for just slugs no numbers, because I've seen what happens to those.
There was some poor site owner seeking assistance on the Let's Encrypt community site because (of course) even though they swear they haven't changed anything now mysteriously Let's Encrypt stopped working and so it must be a bug in Let's Encrypt.
They're using http-01, so the magic files need to be exposed from a /.well-known/ directory and others have got them to try a test file named "test". When you ask for the test file though, what you get is a 30x redirect to some unrelated blog post.
Well, it looks unrelated at first, and then what I realise is, that post is about Testimonials. Sure enough when I ask for a file named 'chris' instead I get redirected to a blog post about Christmas...
I don't think that user ever figured out what their problem actually was, it's a little frustrating but you have to let them go do their thing.
This literal trash foundation is unfortunately how big parts of numerous American cities have been built.
In this case, I feel building on wetlands is the bigger problem.
“At worst, they are made by throwing some dirt over the top of a pile of garbage, and building more city on top of it”
Clearly, there are a set of previously underappreciated risks here. Geology is very much a possible candidate, though other factors might also be at stake. Armchair analysis at a distance and with a specific cause to advance is probably the worst addition to the discussion at this point.
(That's not to say that causes aren't often fairly immediately evident, as with, say, the 737 MAX incidents. But without clear basis for belief, even hunches eventually proved correct are unfounded conclusions.)
I live in Somerset, UK. Just north of where I live is the "Somerset Levels". About 400 years ago a bunch of cloggies (Dutchmen) were engaged to drain the marginal lands for farm land etc. King's Sedgemoor Drain was built later etc. This is the land of Glastonbury (the festival actually happens at a farm in Pilton).
The Neths have centuries of experience of dealing with marginal lands. Your swamps are not going to faze them any more than ours.
Hurricanes are bad, but they don't need to be Katrina-bad.
Engineering solutions rarely cause climate change. I'll grant you that enough concrete pouring might be nasty but I doubt a very small country in Europe, next door to Germany is responsible for all of it.
Piss off.
This is true for areas that are earthquake or fire-prone. But especially areas that are vulnerable to sea-level rise due to climate change.
If nobody else is going to act, on climate-change (act = change how they do business), it will certainly be the Insurance companies who will act. They have a great deal to lose. And they do not profit by buying in to the big lie.
Example: https://en.wikipedia.org/wiki/National_Flood_Insurance_Progr...
Liability caps are used in specific instances where losses might otherwise prove catastrophic to the insurer. The two areas which come immediately to mind (and no, I'm not versed in the industry though I did in fact study it, lightly, in school), are major disaster property insurance (flood, hurricane, earthquake), and liability caps (general liability, medical malpractice). Both are specific to how insurance works, at least in theory.
The most usual basis of insurance is risk pooling, largely for uncorrelated and individual risks. Premiums covering house fires, automobile property and liability damage, workplace injury, or shipping, tend to cover (from the perspective of the insurer) relative small claims which tend to occur predictably and independently.
Where caps are imposed, either predictability or correlation tend to be less manageable. The insurance sector has long lobbied against tort policies favouring claimants, and argued that tort liability claims have been skyrocketing. I studied the tort liability crisis of the 1980s in particular, and have kept an eye on this issue in the decades since. In truth, the 1980s crisis owed far more to the inflation surge, and remission, of the late 1970s and early 1980s. With inflation came higher (nominal) returns on investment returns, which is where insurance companies invest premium payments pending payouts. While the industry was screaming "out of control court judgements", the reality seemed far more to be one of getting whipsawed by the (pre-inflation) pricing of policies, the (high investment returns) period of low premium rates (subsidised in effect by investment returns), and under the Volker inflation controls and tight-money policies, falling investment returns whilst claims increased, largely in step with inflation. Caps on payments would in this case address the inflation/investment risk side of the business.
Correlated claims is the other situation.
Individual risks --- automobile crashes, house fires, accidents, structural collapses --- tend to be independent of one another. In major widespread events, a large number of correlated claims occur, and can stress the capabilities of even large insurers or the industry as a whole. Floods, earthquakes, hurricanes, major wildfires, tsunamis, ice storms, and drought can affect large areas, ranging from major portions of a single city to regional or continental regions. Though the events are distributed across time, when they occur, they occur everywhere at once, at least within the affected region. Payouts in this case require limitation.
Virtually all insurance policies include exclusions for acts of war or civil disturbance. As with natural disaster, these occur in unpredictable and widespread manners, and are poorly handled by commercial insurance.
Depending on the underlying mechanism for the Surfside building collapse, there might or might not be correlated risks.
If the principle cause is in fact climate-induced geological undermining which could affect large low-lying coastal regions, then yes, it's possible that those zones could simply become uninsurable.
If the principle cause is poor building methods or design, then the risks would be limited to, say, construction by the contractors or designs by the architects in question.
If the principle cause is poor maintenance and inspection processes, then the risks would apply to the specific geopolitical domains affected by those inspections. Surfside, Miami-Dade County, or the State of Florida as a whole might be affected. Here it's likely that the insurance industry, through property owners and residents / tenants of such buildings would be able to impose reforms to the inspection and remediation processes, which gets at another mechanism of insurance itself: of actively managing and mitigating risks, not merely pooling them.
With private insurers, all it takes is one small claim to cancel a policy. Many property owners have no choice but sign up with Citizens when private entities refuse to issue a contract or set the price so high it is simply unaffordable.
But Citizens will also try to offload contracts to small private insurers (that most have never heard of). Then the concern becomes, “will my insurer survive the financial onslaught of claims or go bankrupt before I get my check?”
Seems like building on unstable land is a bit of a solved problem.
Of course very sorry for all the victims and their families, no matter what the root cause.
When you use concrete in large amounts you take standard samples called cubes as you pour and these are subjected to standard tests. In the UK we use a 10x10x10 cm cube and then it's allowed to cure for a standard time in standard conditions and then crushed. There's a bit more to it than that but basically, it is quite easy to demonstrate "standard" concrete and there is not much money to be made with rubbish materials. There are exciting possibilities involving admixtures but that is down to workmanship. Shoddy concrete (whatever that is) is very unlikely but a popular meme.
Conc. for a structure like that may be pre-stressed or at least reinforced. Pre stressed is where you put rods or creatively shaped steel through it and literally squeeze it. Conc is great in compression (pushed/squeezed) but rubbish in tension (pulled apart). Imagine a beam supported at both ends and think of pushing down on it in the middle. It will try to bend in a curve. The top surface will try to get smaller and hence is in compression and the bottom will try to stretch and is in tension. If you drill a hole along the length of your beam near the bottom and stick a steel rod through it and put some washers and nuts on and crank on some compression you now have a sort of model for pre stressed concrete. The steel rod is ace in tension and gives the concrete beam a lot more strength. Embedding steel mesh ("rebar" or reinforcement bars and the like) have a similar effect but ...
The thing about pre stressing over adding mesh/rebar is that you are locking away a huge amount of energy into a static structure. There is a huge gain to be had in reduced thickness of conc and hence weight which means its a double win but you also need to ensure that the "rods" (in our model, not quite reality) never fail. If they do fail then it's normally rapid not just a gradual fail. The effect of prestressing can happen by accident in "normal" meshed conc. Most digger drivers that have used a pile driver attachment to break large chunks of conc. will have tales to tell of large lumps of conc suddenly exploding. Fishermen often tell tales of the one that got away ... 8) However it can happen.
So I hope I've shown that shoddy concrete itself is unlikely. There are far more ways for a structure to fail than that. Workmanship is possible but for my money the ground basically dropped away from under the structure and it sort of exploded and imploded simultaneously. I can't put this any other way but it seemed to fail completely in every way possible, simultaneously.
It is the most horrible thing to watch and will haunt us forever.
>Tweeter reported three other on-site inspections in July, August and October, but the GPS records show her vehicle stopping at the Hard Rock on just one of those dates.
the Hard Rock New Orleans could have been insufficient supports changed after the city approved plans [2].
>The last set of plans approved by the city were dated June 2018. Those called for the sturdier 16-gauge metal decking. Those plans were revised to go with the thinner, lighter 22-gauge decking in February 2019, shortly after the emails between the construction team and New Millennium. The city confirmed it never received those revisions.
[1] https://www.wwltv.com/article/news/investigations/city-was-c...
[2] https://www.wwltv.com/article/news/investigations/david-hamm...
Maybe what you say rules it out anyway, but can concrete deteriorate over time? Eg maybe it was up to strength at the time, but somehow weakened over the 40 years? I don’t know anything about concrete...
There are loads of possibilities but at the moment I think foundation failure is most likely. Unless you pile down to bedrock or build a gigantic raft of conc. then you need very stable land for a building that size. Another other option is to build it flexible but that was obviously not the case. The geology there is likely to be a nightmare. Miami is a lot of reclaimed land, low lying and next door to the Atlantic.
The sight of the collapse is something I won't forget in a hurry. The secondary collapse on the right in the security camera footage took about three seconds. That's insanely fast. The failure was absolutely catastrophic. It wasn't simply a cascade - the whole structure seemed to fail simultaneously from top to bottom and that is not normal.
When I asked the realtor about it, she just said, "there's a reason it's called Sand Hill Road".
Look at the land around Portuguese Bend in Los Angeles County. The water line is above ground because the pipes break if they're buried(that's a lot of movement though).
It hasn't been an issue.
Much of the Financial District / SOMA are on fill.
Pictured in red on this map, generally the north and eastern sides of the city.
https://escweb.wr.usgs.gov/nsmp-data/Presentations/san_franc...
https://www.atlasobscura.com/places/the-old-ship-saloon-san-...
All of Mission Bay and the Marina used to be underwater:
https://www.smallcarbigtimetours.com/san-franciscos-original...
Coastal land near ports and rivers, is particularly rare.
There were. I'm not a civil/structural engineer and I don't know how common this kind of thing is.
> One condo owner sued the unit association for failing to fix the cracks in the outside wall of her unit in 2015, according to a lawsuit filed in Miami-Dade County. The condo owner, who could not be reached for comment, said the cracks led to water damage that cost $15,000. The court documents noted that because the cracks were a structural issue the building association was liable for the expense.
> The condo owner had previously filed a lawsuit against the building association in 2001 due to a similar issue. The two sides settled outside of court, but that kind of cracking is described as “of interest” in the county’s Structural Recertification Form.
I read another article about a resident complaining about cracking near the pool deck.
https://www.nbcnews.com/news/us-news/cause-miami-condo-colla...
That is indeed much more than the 2mm it was sinking each year.
But wait...the temperature swings of the frame, and other interior parts of the building, is going to be a lot less than the outside temperature. That's going to cut that 40mm horizontal and 16mm vertical expansion way down.
Also normal thermal expansion alternates with normal thermal contraction, so wouldn't it average out to close to zero net movement over the course of each year, with a small net expansion due to climate change (Florida average temperature is up under 0.5℃ since that building was built)?
Sinking, on the other hand, is usually cumulative. 2mm/year over 40 years is 80mm. So you've got a building designed to expand and contract, staying within some range, having a net vertical movement imposed on it that is a lot larger, and probably a lot less uniform.
"The United States Geological Survey recorded the explosion as a 3.9 magnitude earthquake about 161 kilometers off the coast of Florida."
https://www.wavy.com/news/military/navy/whoa-u-s-navy-releas...
The pictures I have seen make foundational failure look more likely.
Talks about it in this article
I wonder how Miami fares if they take a direct hit from an Andrew force hurricane, or a hurricane that drops 40+ inches of rain?
Before Hurricane Andrew hit in 1992, the region had not been impacted by a significant storm in years and there was a very lax attitude toward building codes. Many places built in the 1980s we’re not always constructed with the most sound practices [1], builders were taking shortcuts and local government turned a blind eye to the issue.
Andrew changed everyone’s thinking after the “new” neighborhood of CountryWalk was flattened [2]. Some of the strictest building codes in the nation were implemented — and enforced — after Andrew.
But the lax attitude has returned. For instance, in the past decade, I’ve seen new multi-level residential buildings constructed with wood (instead of concrete) above the second floor, wondering how such construction even receives approval given the building code.
But it is happening, and the majority non-native, transient population has no clue the overpriced real estate they’ve purchased may not be suited to handle a major storm. They will face a reckoning if this day ever comes.
I would advise anyone looking to buy down here to do your due diligence. Hire a good inspector and engineer to examine your potential purchase, as well as a lawyer to make sure all repairs or improvements were all done above board.
[1] https://www.miamiherald.com/news/local/community/miami-dade/...
[2] https://en.m.wikipedia.org/wiki/Country_Walk,_Florida#Histor...
Maybe all buildings over 3 stories need more frequent and detailed periodic structural fatigue/engineering assessments, eh?
it's people preferred to still profit as much as possible from this dying building instead of renovating/repairing it
that is what you get for building a civilization where profit has higher priority than safety of your people
Having an ideological axe to grind like this one is a major risk to your intellectual integrity. It can blind you to reality, or worse, it can make it so you don't actually care what is real anymore.
They knew about it and let it happen so insurance can help them with financial support
The result of the investigation will be: "natural cause"
> Having an ideological axe to grind like this one is a major risk to your intellectual integrity. It can blind you to reality, or worse, it can make it so you don't actually care what is real anymore.
Yup yup, i am so blind that i don't even have to work anymore, i abused this civilization and made insane profits, i no longer have to worry about needing money anymore
Yup yup, i am blind, i don't care waht is real anymore
Yup yup, enjoying my life as a king in thailand
Again, you're positing this shadowy "they" who somehow saved a lot of money — but the building was owned by the people who lived there, and I'm pretty sure if the condo owners actually knew about the renovations that needed doing, they'd have spent the money to make the repairs, rather than getting crushed to death in their sleep.
There is no one enjoying ill-gotten gains here.
> Yup yup, enjoying my life as a king in thailand
I see. A tyrant.
Well if it's found that the construction/design of the building is at fault, then it will be the developers.
https://en.wikipedia.org/wiki/Landfill
Parts of Boston and Manhattan are built on reclaimed land.
https://www.nationalgeographic.com/culture/article/Boston-la...
https://gizmodo.com/watch-new-york-city-s-boundaries-expand-...
> Land reclamation, usually known as reclamation, and also known as land fill (not to be confused with a waste landfill)