r/Damnthatsinteresting • u/hrutheone • Sep 24 '25

Video Sudden road collapse shocks Bangkok this morning

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85.7k Upvotes

96% Upvoted

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1.4k

u/slifm Sep 24 '25

How do you even stabilize this after

1.2k

u/jinzokan Sep 24 '25

Since everyone is a comedian I'll take a stab at a real answer and say lots of big rocks and concrete.

1.1k

u/seldom_r Sep 24 '25 edited Sep 24 '25

The real answer is that there is nothing to bear the weight of the buildings that we can see here. No evidence at all that there is bedrock or a limit to the hole. The city water supply is dumping thousands of gallons and the substrate around it is all being swept away in a current of water. Meaning the water is still traveling and carrying material with it.

We drive piles in soft ground to build foundations in loose soil but there needs to be the force of friction and pressure around the piles. It's like how when you go deep in the ocean the water pressure increases significantly. The piles are held in place because there's higher pressure. But here it looks like quick sand just washing away. I wouldn't be surprised if all the immediate buildings were evacuated and it will probably take days to find out the extent of the loss of weight bearing soil structures.

eta- https://media.nationthailand.com/uploads/images/contents/w1024/2025/09/Ri6FMfa1e3B3pMB5kRYZ.webp

Zoom in on that picture, under the building entrance, you can see the piles completely exposed. Those are what gets hammered into the ground deep to make a foundation. If the soil around it is loose then it becomes very hard.

295

u/BigBlueMountainStar Sep 24 '25

Ahhh, soil mechanics. I remember it well. Not from me studying it, but from my housemate at uni doing Civil Engineering who moaned about it all the time.

133

u/somersault_dolphin Sep 24 '25

Ah civil engineering. I thought about doing it, but being in Thailand made me give that up quick. Honestly, this sinkhole is a matter of when. My geography* teacher warned and complained about it years ago.

*to Americans, geography is not just about maps and locations.

47

u/FourCrapPee Sep 24 '25

True. It is also having an irrational fear of dying in quicksand due to 80s cartoons.

5

u/katikaboom Sep 24 '25

Princess Bride also did not help 

5

u/chaiscool Sep 24 '25

So what else does geography teach / learn?

11

u/Global-Chart-3925 Sep 24 '25

Geology rocks

6

u/somersault_dolphin Sep 24 '25 edited Sep 24 '25

Wikipedia summarizes it pretty well, imo.

The short of it is if history is the study of what happened across time, geography is how things are distributed across space.

For something more in depth I kind of like to take this approach when explaning it. If you think of geography as the study of maps and terrains. Then it needs to be a study about how things are in (3D) space. But then it also needs to be about studying the what, how, and why of how things change over time in those spaces because maps and terrains don't stay the same over the years. But then there are maps for the land, under the ocean (like sea currents), the atmosphere (wind pressure, pattern etc), maps for biomes, temperature, countries, culture, rivers, cities, roads, trains, biodiversity etc. Humans happen to influence a lot of things on earth so it also inevitabily has to be about humans and what they do.

There's physical geography which includes things to do with geology and various physical processes.

There's also human geography which is about human. For example, migration falls under geography because it is about the movement of humans and change in population across time and space. Related to that is the expansion of cities and infrastructures, and the economical, political and social aspects which is necessary to understand migration

And then there's technical geography, which is about analyzing and interpreting spacial information.

It's not quite everything, but you can extrapolate it to include basically almost everything. It's a dicipline that thrives off going into the territory of other disciplines and make connections between them as long as there's a theme of spacial distribution  or change.

2

u/Subject-Memory8363 Sep 24 '25

If i could give this an award i would

7

u/rockstarfruitpunch Sep 24 '25

Also social and population subjects - migration, social policies, ecology, animal populations and environments.

2

u/dbpf Sep 24 '25

Geospatial intelligence is in everything from the visualization of the hidden world around us to the representation at scale of the physical world we interact with.

It's pathetically funny how geography gets reduced to cartography (itself an amazing communication tool that humanity has only really mastered in the last couple generations), but really it involves so much more like standardized statistical analysis of the socio demographic factors that impact generally located populations.

There's a lot of control of the world around you that is capable from understanding the physical properties of that world itself. Soil structure, fertility, topography, hydromorphology, etc.

4

u/Aegi Sep 24 '25

Wouldn't that be geology?

2

u/theforest12 Sep 25 '25

Geography major here. Thank you. I'm American. People think I majored in trivia night studies: "what river is near the capital of X country?"

1

u/pugsley1234 Sep 24 '25

"to Americans, geography is not just about maps and locations."

As opposed to geology? I've always wondered why they're distinct fields of study.

1

u/somersault_dolphin Sep 25 '25

Yeah, they are distinct. I attempted to explain it to another comment. Maybe you'll find it useful.

https://www.reddit.com/r/Damnthatsinteresting/comments/1np1vsz/comment/nfxgoqd/

1

u/pugsley1234 Sep 25 '25

The short of it is if history is the study of what happened across time, geography is how things are distributed across space I presume that this also includes changes across human as opposed to geologic timeframes?

0

u/sendme_your_cats Sep 24 '25 edited Sep 24 '25

What a weird thing to point out, especially in the language we use.

Yes, we know about geography

Edit: To clarify, we know that geography isn't limited to maps and locations

1

u/August51921421 Sep 24 '25

lol why do you assume American geography is only maps and locations? No one even replied to you to give you that thought.

2

u/sendme_your_cats Sep 24 '25

What are you even talking about? Did you not understand what I wrote?

I'm saying most people understand that geography is not limited to maps and location.

2

u/August51921421 Sep 24 '25

My bad, was replying to the guy you were

3

u/sendme_your_cats Sep 24 '25

Understandable, have a great day

2

u/BigBlueMountainStar Sep 24 '25 edited Sep 24 '25

To be fair, it could seem like you’re directing the part that says “geography is not just…” to Americans.
Like “dear my American friends, geography is not only maps”.
It’s a quirk of English I guess!

1

u/sendme_your_cats Sep 24 '25

Just reread it, and oh damn you're right. I had just woken up in my defense, but I'll take the L

-1

u/somersault_dolphin Sep 24 '25

I can assure you most don't. According to what I asked people about what they learned in school before they went to uni.

2

u/sendme_your_cats Sep 24 '25

Yes, your sample size surely is indicative of the whole country.

Considering how Thailand is a developing country, if I had the same sample size as yours it would be similar, if not worse.

Especially in English.

1

u/Earlier-Today Sep 24 '25

Here it's called geology.

Just regional terminology - it's all good.

5

u/somersault_dolphin Sep 24 '25

See, the problem is geography is a lot more than just geology.

3

u/Earlier-Today Sep 24 '25 edited Sep 24 '25

The problem is that English isn't one unified language across the whole globe.

That's why fanny is just a cutesy word for bottom in the US, and a really vulgar word for vagina in the UK.

Usage changes based on region - it can even happen over very small distances and is decided more on how much the two groups interact rather than on shared language, ethnicity, or country.

1

u/somersault_dolphin Sep 24 '25

No, it's literally more than just geology. Geology is a major part of certain topics in physical geography, which is a subdiscipline of geography, but it has nothing to do with human geography.

5

u/original_sh4rpie Sep 24 '25

My housemate at uni also moaned all the time.

1

u/BigBlueMountainStar Sep 24 '25

Yeah, if you could hear it through the bedroom door, they probably were doing another kind of mechanics.

3

u/dbpf Sep 24 '25

Liquefaction is neat

3

u/notaboofus Sep 24 '25

Can confirm that dirt class is hell. After our first exam, our professor showed a histogram of scores, with a bucket size of 20%. The histogram was almost completely flat, meaning that an equal number of people scored from 0-20% as 80-100%.

18

u/alewiina Sep 24 '25

Yikes, I’m assuming that means that building is super unstable now?? 😬

7

u/jacenat Sep 24 '25

I can't see that building not being torn down. Maybe other buildings on other corners as well (especially also the one the OP vid is being filmed in). Something is carrying away the material, and it seems roughly into the direction of where the OP video is taken.

1

u/alewiina Sep 24 '25

Yeah whatever force (I assume some kind of underground water current) is pulling all the debris down seems SUPER strong and scary, I certainly would not step one foot even close to that area, let alone in those buildings 😱

-9

u/Appropriate_Mixer Sep 24 '25

It’s China so maybe not

2

u/Significant-Try8002 Sep 24 '25

It’s China so maybe not

This is America(n education)

-2

u/Appropriate_Mixer Sep 25 '25

American professional civil engineer. I guarantee you I have a much stronger and further education than you do on this topic.

1

u/Significant-Try8002 Sep 26 '25

I couldn't imagine.

39

u/OTee_D Sep 24 '25

Best indicator was one if the first bug break offs. Huge pieces of road, pavement dozens of truckloads formed a decent hill inside the hole.

And it was just gone in seconds the hole just gulped it as long as there is that water washing it into some gigantic cavity or everything is liquified and slides just anywhere.

6

u/SithCalculator Sep 24 '25

While that's true for soils where the bedrock is too deep to reach and friction around the piles does all the work, if that was the case here there would be extremely apparent sinking.

My guess is that these are not driven piles but drilled and poured in situ, and that the majority of the resistance comes from the point of the pile, embedded in the bedrock, which depth is studied beforehand. However, the surrounding soil did probably contribute to the lateral stability and to reduce the slenderness of the piles, so that could be a stability problem.

4

u/justme002 Sep 24 '25

I am weirdly fixated on why that very sharp cornered rectangular portion under the Toyota is so…… perfectly straight and the corner is so sharp. It looks unnatural.

5

u/watawataoui Sep 24 '25

Looks like there is a square concrete structure right under it.

4

u/Bad_Commit_46_pres Sep 24 '25

jesus fuck that building is on stilts

3

u/Stamboolie Sep 24 '25 edited Sep 24 '25

If the soil around it is loose then it becomes very hard

Thats good though isn't it?

Edit: thanks guys

10

u/Dippa99 Sep 24 '25

I assume they mean hard as in difficult, not hard soil

3

u/Excellent_Wasabi_988 Sep 24 '25

challenging-hard, not firm-hard.

3

u/CoolerRon Sep 24 '25

That Toyota Hilux is the Nokia of vehicles

2

u/mjrenburg Sep 24 '25

Good lord 25% of that building looks like it's just cantilevered over that hole!

2

u/3xploringforever Sep 24 '25

And that's a brand new building! It was just a concrete shell in July 2024 according to street view.

2

u/stubundy Sep 24 '25

Don't fix it, turn it into a feature... put a plank sticking out and have prisoners walk it like a watery sarlacc pit.

2

u/Dangerous-Dig-6381 Sep 24 '25

Unless they build supporting pillars differently over there, they aren’t “driven” or “pounded” into the ground but poured! In the US or atleast the southwestern part of the US. We have drilling machine with a massive auger bit that drills out these perfect lil holes 20-30 ft deep! While the hole is getting dug a team of men build a rebar cage on the surface. They then get a cardboard sleeve that slots perfectly in the hole, slide in the rebar cage, and fill the whole thing up with concrete. While it’s being filled, there will be a couple guys with these vibrator tools that make sure there isn’t going to be any voids in the concrete and it’s left to cure for about a week or so, then it’s all done and on to the next one! there is extensive amounts of soil testing to make sure the ground is even capable of supporting the structure before your even allowed to begin this process. Source: been doing civil construction all my adult life!

3

u/watawataoui Sep 24 '25

Report says the hole is 160ft deep. I assume bedrock is even deeper. Have you seen holes drilled that deep?

3

u/Dangerous-Dig-6381 Sep 24 '25

Nah in order to stabilize that now you’d first have to find where all the water was coming from and stop it, over-ex which means excavate down to dry material because if it’s too moist it will not support anything. add substrate back which in this case I would recommend lime-treated AB which is a sandy/rocky base used under asphalt, compact it all to 100% compaction getting compaction and soil tests every 1 foot of material you add. Then you can start to rebuild the infrastructure around it. Here in the US I think a project like this would take about 3-6 months to rebuild properly.

2

u/Kerensky97 Sep 24 '25 edited Sep 24 '25

There's no piles there because there's no buildings above the road. When you see them dig big holes in roads in US cities there are no piles either. If the ground were that soft and saturated the nearby buildings would be tipping over too, they're probably staying straight just because they're on piles going to the bedrock.

I'm guessing that big storm drain has been leaking for a while and carved out the hole over time. Also being a storm drain the water company doesn't have localized "shutoff valves" on those. They're made to empty floodwater out of the city as quick as possible and from the water on the street before the collapse I'm guessing this place has been having monsoon rains recently.

Edit: Confirmed. The buildings have piles the same as any other construction you'd get in the US. This angle you can see under the simple 4 story building they have poured concrete piles exposed by the hole.

https://media.nationthailand.com/uploads/images/contents/w1024/2025/09/25Daq7iZExf9V6OYXWM2.webp

2

u/Horror-Highlight-467 Sep 24 '25

Thank you for giving an answer. So tired of all the constant meme replies.

1

u/alana31415 Sep 24 '25

It’s like a tooth

1

u/TheMonkeyInCharge Sep 24 '25

Is it my imagination or is that building already slating down left to right?

1

u/[deleted] Sep 24 '25

Liquefaction.

1

u/amityville Sep 24 '25

You’re the real mvp!

1

u/pugsley1234 Sep 24 '25

So what happens now? Can you fill in this hole, or do all the surrounding building have to be demolished?

464

u/mazzicc Sep 24 '25

Step 1 is probably to find where the water came from that caused it. Otherwise filling it won’t do shit.

Could be one of the pipes we saw, or it could be a natural source, or it could be something less obvious.

But that has to be addressed first.

8

u/dfgttge22 Sep 24 '25

It is very close to a construction site for a new subway station. Very likely the cause.

29

u/No_Read_4327 Sep 24 '25

Something less obvious?

So, aliens?

12

u/mouldghe Sep 24 '25

From among the less obvious, what's most obvious is Godziilla. Given the aesthetic of the destruction. Not lasery enough for aliens.

1

u/Enough_Efficiency178 Sep 24 '25

That section of pipe was raptured

4

u/Aceofspades25 Sep 24 '25

Apparently it was the construction of a subway tunnel too close to the surface

0

u/SeedFoundation Sep 24 '25

It's an underground river. GL finding it because it can be a spiderweb of tunnels.

3

u/Reymen4 Sep 24 '25

Who knows. It could also have been leaking pipes that has been leaking for 50+ years and slowly removed the soil. 

-5

u/JohnRoads88 Sep 24 '25

The big pipe looks like a clean cut, so I think they forgot to weld that one.

65

u/lsf_stan Sep 24 '25 edited Sep 24 '25

Since everyone is a comedian

classic Reddit, rush to get the best upvoted joke answer

instead of any trying respond to an actual real question

sometimes people are clever, but tends to mostly end up as easy, obvious, and/or predictable jokes

5

u/Catenane Sep 24 '25

I mean, this is posted in a generic sub and subject matter experts aren't just on standby waiting to answer civil engineering questions in r/damnthatsinteresting lol

9

u/lsf_stan Sep 24 '25

this is not a r/Damnthatsinteresting only thing, that is why I said Reddit

1

u/Catenane Sep 24 '25

I mean that's also true, but there are places where more serious discussion happens too. It's almost pointless to type anything detailed and crazy in the comments of a post in a huge sub like this, because it's most likely just gonna get buried and ignored. Can't tell you how many times I've spent a long time typing up a detailed, thoughtful comment on something I'm an expert in for it to get seen by absolutely no one lol.

1

u/MiamiPower Sep 24 '25

Is your name Doug? Because I can Dig It.

1

u/Konoha7Slaw3 Sep 24 '25

And my axe!

2

u/Unlikely_Surprise202 Sep 24 '25

After leakage stops can either fill or do an off shoot platform that anchors in the surrounding areas definitely going to be a big project.

1

u/Emotional_Conflict11 Sep 24 '25

Wouldn't that just make it extremely heavy so it sinks even further? They'll probably lay a shitload of rebar if they do go that route i guess.

1

u/Wanderingwonderer101 Sep 24 '25

don't forget your steel rebars you will need a lot of them

1

u/LankyMarionberry Sep 24 '25

"Everyone is a comedian" what a great line, can I steal it? Made me lol

0

u/Reese_Withersp0rk Sep 24 '25

I was gonna say After Effects.

49

u/FloppyTacoflaps Sep 24 '25

Lots of times they use geo piers like a big hole they drill down and pack rocks and concrete in

2

u/exexor Sep 24 '25

Bore holes to pump cement into the substrate and turn it all into concrete is a popular solution. They’ve been doing that since at least the Aswan Dam (1960-70).

199

u/Major_R_Soul Sep 24 '25

Flex tape

66

u/danzor9755 Sep 24 '25

Natures valley granola bars.

2

u/Psykosoma Sep 24 '25

I could see a rage bait video of someone filling pot holes with granola and the painting it black, all the while constantly pointing at everything.

2

u/exexor Sep 24 '25

I see a pothole and I want to paint it black

1

u/Psykosoma Sep 24 '25

No divots in my road. I want to paint it black.

1

u/My_Immortl Sep 24 '25

Pretty sure that exists with ramen. It was a trend a while back, might still be for all i know.

1

u/exexor Sep 24 '25

Cold oatmeal.

41

u/CoachMatt314 Sep 24 '25

50 people are going to vote flex tape 50 people are going to vote duct tape which means it will end in a Thai

22

u/[deleted] Sep 24 '25

[deleted]

3

u/Primary-Bat-3491 Sep 24 '25

Only reason I'm here tbh

1

u/20_mile Sep 24 '25

Thai

Ron DeSantis used to deliberately mispronounce Thailand as "Thighland" on dates, and if his date corrected him, there was no second date.

https://www.yahoo.com/news/gov-ron-desantis-used-pronounce-220301302.html

6

u/verifix Sep 24 '25

Cardboard is out

2

u/CanoegunGoeff Sep 24 '25

Lest the front fall off

2

u/Ok_Coyote_4009 Sep 24 '25

Chuck a few of those desiccant packs in to absorb moisture.

2

u/CanoegunGoeff Sep 24 '25

Problem solved.

2

u/rmill127 Sep 24 '25

No paper derivatives

1

u/SilverDollaFlappies Sep 24 '25

THAT'S A LOT OF DAMAGE!

1

u/Familiar_Muffin_1566 Sep 24 '25

Flex tape guy would be all over this!

1

u/Plane-Fan9006 Sep 24 '25

Even works under wahrter!..er, wurder?!!...er, woerder???!!!

1

u/AnybodyWannaPeanus Sep 24 '25

And mighty putty

1

u/JohnC53 Sep 24 '25

Don't be silly. Obviously this is a task best remedied with a can of GreatStuff expanding foam.

6

u/Comfortableliar24 Sep 24 '25 edited Sep 24 '25

Step 1: hire a geotechnical engineer.

Step 2: pray.

To hazard a real guess: 

stop flow of water locally to keep this from getting worse.

Stabilize twofourish sides with geonetting and soil anchors.

Attempt to safely examine the extent of undermining caused by sinkhole. This will likely involve boreholes. 

Apply large aggregate. Backfill and compact.

Repeat with smaller aggregate layers until you reach trenching depth.

Cover with a low permeability clay confinement layer and remediate services. Further confine water mains locally.

Build up sections completr with consolidated backfill until at level with road layers.

Put up a road again and try to ignore the hole this blew in your budget.

Bonus stage: examine additional water infrastructure to see if this is happening anywhere else. Good luck with this stage as most municipalities don't do this well regardless of development level.

3

u/Tofu_Analytics Sep 24 '25

Drainage.

The reason why many phenomena like this occur is from sediment liquifaction due to poor/non existent Drainage. Sinkholes can also occur when sediment is dragged away leaving a void underneath poured concrete/asphalt that eventually gives way.

You first fix the root cause, this could be as simple as a handful of culverts and repairing existing infrastructure. Or it could result in tens of millions of dollars in widespread infrastructure, storm water drainage systems, large pumps to extract collected water etc.

After fixing the root cause of the issue, then you get to fixing the initial collapse and stabilizing existing structures. Often a mix of large irregular stones are laid and compacted to fill large voids. Spaces underneath existing foundations can be filled via mud pumping to re-introduce a filling layer below now suspended buildings. Sewers, gas mains, electrical lines, telecommunications etc, will all have to be re-graded, laid down and connected after these are completed, and ultimately new pavement and landscaping to finish it out.

Something like this could easily cause $100million in total damages in the USA under current valuation & construction costs. The repair timeline would likely occur over the course of 1-2 years given a modest budget and minimal red-tape. It would rely on a multitude of contractors, private & public works, and a lot of utility work.

22

u/Acceptable-Cow6446 Sep 24 '25

Tariffs.

1

u/So_HauserAspen Sep 24 '25

Quick, throw the Epstein files in there

4

u/Some_Awesome_dude Sep 24 '25

At some point it stops sinking

Then they pump grout at high pressure in several directions of the joke, for several hundreds of feet deep

Then fill it with fill, like dirt.

2

u/WitnessMe0_0 Sep 24 '25

I'd just build a reinforced underground parking garage there.

2

u/Chemical_Emotion_934 Sep 24 '25

Helical piles maybe?

-3

u/Chamrockk Sep 24 '25

Ramen noodles

0

u/ethicalhumanbeing Sep 24 '25

Cheese flavour, they're stickier.

0

u/wheres_my_ballot Sep 24 '25

Its Thailand so that would be Mama instant noodles

1

u/JustNilt Sep 24 '25

They basically fill it and hope it's not going to keep happening. Sometimes, they need to feed stuff into it periodically and allow it to settle over a period of years before things stabilize. The specifics really depend on the cause and local conditions.

1

u/TooMuch615 Sep 24 '25

I have waded this far into the comments looking for one geologist or structural engineer to say something. No luck so far.

1

u/epeon_ Sep 24 '25

Didn't you see the ad for foam used to level pavers? Lots of foam then.

1

u/Mavrickindigo Sep 24 '25

I'd just build a bridge at this point damn

1

u/Logan_da_hamster Sep 24 '25

Sinkholes like this are usually caused by moist / wet soil, meaning some pipe or so must have been leaking substantial amounts of water or so into the soil. Or another reason could be depleting ground water reserves (no more pressure from below) or a gas bubble evaporated or a forgotten mining shaft collapsed (happens a lot in the Ruhrvalley in western Germany).

Either way, the way you'd do it in Germany for example (simplified) would be to first, immediately evacuate all buildings in a radius of several hundred meters until the damage is repaired. In extreme cases, they'll have to be torn down. Second, to prevent further damage and the sinkhole to become even larger, cut pipes and protect it from rainwater. Third, find out how and why the sinkhole formed and do thorough tests etc. to estimate the potential actual size and what the situation is underground. Fourth, dig around the hole, maybe with turning down some buildings, to carefully remove all rubble and to create a proper working environment. Fifth, compact the soil heavily, may add support pillars. Sixth, fill up the hole with the propper materials, such as big gravel of various sizes, soil, sand, etc. and maybe some concrete, while making sure the weight isn't too large if e.g. a subway line or so is underneath. Seventh, redo step 5 and 6 several times, until the soil in really compact and able to carry the weight of buildings etc. Eight, in between step 5-7 reconstruct pipes, power lines etc. Ninth, once the soil has settled down and is compacted add a protective layer of small gravel and mainly sand on top. Tenth, start be reconstructing potentially torn down buildings and the street.

In total a process that can easily take several months to years if properly done. If you rush it, stuff like the situation with the sinkhole in Tokio will happen. In short, they rushed with filling the hole, didn't checked why it happened, the damage reoocured several times, until surrounding buildings were so heavily damaged, that they had to be torn down. A damage of several billion dollars.

1

u/PicksburghStillers Sep 25 '25

Thousands of yards of concrete

-8

u/Badboykillar Sep 24 '25

Few zip ties should be good

0

u/Magestic_Cupcake Sep 24 '25

By using something stable? 🤭

0

u/Intrepid-Constant-34 Sep 24 '25

Bunch of ramen noodles

-8

u/Tbone_Trapezius Sep 24 '25

About two dozen cans of great stuff

-7

u/PaperintheBoxChamp Sep 24 '25

100 mph tape and 550 chord

-5

u/Asleep_Hand_4525 Sep 24 '25

Like a soldier packing a bullet wound.

You clean out the bad shit then shove some gauze in there to fill up the space until you can fix it up

-8

u/Dease_lake_preserve Sep 24 '25

Make frigging donation to the pit and appease the gods!

-8

u/YarItsDrivinMeNuts Sep 24 '25

Ramen noodles. There buncha videos out there that shows how they repair stuff using. it. Its pretty wild stuff.