I managed to garble the description of InSAR terms in the video. Here is the correction ● Overview- Interferometric Synthetic Aperture Radar (InSAR) is a remote sensing technology used to measure ground surface deformation with high precision. It works by comparing radar signals from two or more passes of a satellite or aircraft over the same area. By analyzing the phase difference between these radar signals, InSAR can detect minute changes in the Earth's surface over time.
next...... railway bridge closed !! Die Eisenbahnbrücke in Radeberg ist ab sofort voll gesperrt. Die Brücke hatte bei der regulären Untersuchung im August die Zustandsnote 3,5 erhalten. Das gilt beim Brücken-TÜV als ungenügender Bauwerkszustand. Seit dem Einsturz der Carolabrücke in Dresden sind Behörden deutschlandweit für die Zustände ihrer Brücken sensibilisiert.
@@SteppingR They are aware of it for at least the last 10 years. I'm living on the A45 (Sauerlandlinie). There are more bridges than road segments on this highway. All with pretty much same age as Carolabrücke and most are reconstructed or in the process. It's a continous construction site for at least the last 10 years. One miss of @CaseyJones-Engineer is that Carolabrücke was already under supervision of Technical University Dresden. So the experteese was obviously already top notch. The other side of the bridge was already reconstructed. The failing side due to for next year. So a highly unlikely timing. Whats still myseriously is that it collapsed empty. It's used continously for the tram. These vehicles are relatively heavy. So a construction near collapse would have been expected to collapse with this heavy load on top, not empty, minutes after the last tram. @xxxy9928 in case of Deutsche Bahn (DB) it was more the problem that maintainance was the responsibility of DB, while new construction is fedral responsibility. So maintainance was intentionally cut by DB to save money and move the reconstruction cost to federal budgets.
The bridge had monitoring equipment placed on it, and it was known it was failing, that's why it was supposed to be replaced, but the monitoring did not predict an imminent failure. Problem with the kind design from that era is that, unlike today, it was built without any means to inspect the tension cables and measure their load. It is also a well known problem and affects also bridges in West, and we have a number of these bridges in Berlin, mostly train bridges, and they are all in the process of being completely replaced. Also, German bridges are built with 100 years intended life time, and these tension concrete bridges are now being replaced with completely different types of bridges that do last longer than 50 years and can be better inspected and repaired.
It was abput to be replaced but analysis a few months prior indicated that it was no risk. The high temps during the summer probably pur it under stress and the the sharp drop in temps caused it to fail.
The biggest problem in these cases in Europe is the bureaucracy. The bridge fell before all architects, preservationists, nature activists, amateur architects among citizens, and politicians finding a way how to get the contract for his brother's company got to an agreement.
It was not to be replaced, the renovation was scheduled for 2025, the other parts of the bridge were renovated the prior years and now they have to write off those costs, coz they also have to be torn down.
Your channel is popular because it is interesting, professional and honest with no sensationalism for clicks. It would be interesting to look back at historic images of the Millennium Tower in San Fransisco to see any movement and whether it correlates with that reported.
The city officials in Dresden were well aware of the problem prior to the incident. They dont need satellite data to know that there is a problem - those bridges are inspected on the ground, in frequent intervals. They knew that the bridge was damaged, and some repairs have been done on the other side. More repairs were planned to happen soonish. Too late for that now. The bridge will be completely demolished and a new one build. You see, this is not a isolated incident. We have about 7000 bridges in Germany that were build from reenforced concrete during the 50s, 60s and 70s, as a reaction to the economical boom after WW2. That happened in West Germany as well as in the former communist GDR, where Dresden is located. Unfortunatly politics have neglected to take the neccessary steps to maintain this infrastucture in a proper way and rather spend the money on other things. I'd bet this won't be the only bridge that collapses in the coming years. And it won't always happen at 3 am, when nobody is around.
I'd trust a bridge in East Germany as much as I'd trust a bridge in Russia. These post Soviet places are rotten to the core with corruption and corner cutting. The people there still have no pride in community or society.
In a way that monitoring already exists. There's the "Bodenbewegungsdienst Deutschland" ("Ground movement service Germany"), a part of an European project of all countries that participate in the Sentinel mission. It's specifically tasked to use this exact data to monitor the countries for ground movements (landslides, sinkholes, mine shaft collapses, etc), and does not look at bridges and the like. They have a freely available web portal (I'll try to link it in a reply to this comment). Unfortunately, unlike the commercial provider, they exclude bridges for the most part. But it should be (more or less) straightforward to expand that project to infrastructure!
There was a TV program years ago called Person of Interest. A super dooper supercomputer monitoring phone calls and CC TV cameras noticed individual behavior and predicted upcoming crimes. The hero was able to intervene on the side of the good guys. Ridiculous, right? This video left me wide eyed. Predictive analytics! Wow! Now all we need are heroes who will do something with the data in time! Great video! Thanks, Casey. 👍🏻👏
Interesting...I've not watched tv shows now for more than a decade, but as a precursor to that show were the excellent films, "Brazil" (1985), "Enemy of the State" (1998) and "Minority Report" (2002).
Just to make clear how close this collapse was to a disaster: In the moment of the collapse there actually was traffic on the bridge, just not on the part that fell into the Elbe. There is video footage that shows a car driving over the bridge when it collapsed. The last Tram passed only 3 minutes before the collapse. We were really lucky here. I have crossed that bridge countless times myself, it is quite a strange feeling to think about the bad shape it was in. Just a few weeks before the collapse there was a concert on the banks of the river. The bridge section that collapsed was filled with people - from what I've heard they were even standing on the Tram tracks. It is horrifying to think what could have happened...
This is awesome, bridge inspection from space. I didn't know this technology had been deployed already. I hope you can get a look at the Millennium Tower data. Thank You, this will open up a whole new world of research.
It's a short story about how interesting consecutive data is. While the long story needs to include the very limits: (1) the correlation to temperature was done, (2) the correlation to the river level was not done but could be done, (3) there was intense work done on other parts of the bridge, which includes changed traffic and changed loads by that, also caused by modyfied building materials, modified road surface next to the destroyed bridge part (also different loads on the foundation)...
A technical detail, the three parallel bridge spans were interlinked in some places. The collapsed bridge span tore down the adjacent parallel span by 17 cm (almost 7 inches) before the interlink there broke. The bridge is closed for traffic indefinitely and probably will be demolished completely.
For the InSAR data, it's worth considering added radar reflectors (passive & cheap!) to the structures to create defined sensing points, rather than just accepting the overall 'average' motion that classic InSAR of the generic 'ground' will give. Alternates are to get a dedicated 'stealth' analysis of the radar reflection, given that SAR isn't a direct overhead look, rather it's a sideways look, with trigonometry to determine height shifts. So all the 'stealth' calculations make exactly the same predictions, with an opposite purpose. Here we want to 'see' particular aspects of the structure, rather than hide the structure ;-)
Vielen Dank für dein Video! Ein wirklich gutes Beispiel für das gesellschaftliche Lösungspotential von Internet und Satellitentechnik. Thank you very much for your video! A really good example of the social solution potential of the Internet and satellite technology.
predictive analytics would be (outstanding) smart for ca. 1000 bridges in BRD , which are already behaving with cracks , corrosion or preparing for decay.
I have found iver years if work with state government entities that most often, the process is to get something built. Let the next administration worry about the maintenance, even if that's a consideration. And, even if the money is built into the budget for preventative maintenance, oftentimes, it's gobbled up by another immediate need. Basically, like a deck of cards, nothing happens until a collapse. Once something starts to fail, it all collapses, and then fingers begin wagging.
Over the years I've noticed that one particular party refuses to pay maintenance so they can complain when the other party comes into office and spends money on maintenance. As well as taking money out of a budget because it was earmarked for emergencies. Pennywise,😢 pound foolish. At the city and state level.
As well as refusing to recognize the cost of maintenance when bragging about putting up a new building, justified by the expense of maintaining the old building.
This bridge was up to refurbishment but not considered extra urgent. They got surprised by the collapse. A sign that they need to think about better monitoring methods. The ones they used obviously did not tell them what they needed to know.
The bridge complex was already in the process of refurbishment since 2022, with the partial bridge carrying motor vehicles having been finished - the tram bridge that collapsed was the part planned to be refurbished next.
the bridge was hard to check on due to poor design choice, so they didn't really know for sure still a bit reckless to allow transit before the refurbishment was completed if they had no means to know for sure whether or not the bridge was about to collapse
There’s a bridge known as the steamboat Slough bridge located in northern California near Sacramento. It’s a bascule type bridge that was built in the 1920s. Over the last 20 or 30 years it has been moving closer together. Caltrans is the owner and they keep cutting the steel to make the bridge to adjust the gap to make it operational. but to my knowledge they haven’t identified the cause of this problem. Maybe this type of data could be helpful in this situation?
This was fascinating - I sent the link to our IT guy who is leading our AI/data section. Not sure about usage (yet) - but things keep going forward - hmmm - can you get the same data from the Teton landslide - maybe they can show first how long the land was moving - and second you probably could model the construction work being done to make sure that they don't build it up too fast? Many ideas wandering through my head now - need more coffee to organize them.
Thank you. I am working on obtaining data for Teton Bypass and other projects that I have covered. I think there is a lot of potential here with this technology.
Have a look at this here too: The European Gound Movement Service uses the Sentinel data to monitor countries for risk of landslides, sinkholes, mine cave-ins and things like that. I suppose a module to monitor bridges and other infrastructure could easily be added into their analysis pipeline once it's worked out.
Very Professional engeneering your doing here. But you might want to check the german Wikipedia article to see if it is also only a stup. It changed quite a bit since the collaps but it is in renovation since 2019. Renovation work from 2019 Carola Bridge, looking towards Neustadt (2020) Prefabricated parts made of carbon concrete for the widening of the Carola Bridge Repair work on the Carola Bridge in June 2020. Prefabricated parts made of carbon concrete are used to widen the pedestrian and cycle paths Although the bridge's supporting structure appears to be in good condition, the author Peter Hilbert admits: "The Carola Bridge has suffered considerable damage over the decades."[2] Therefore, the renovation work began in November 2019. In addition, the roadway equipment and design were to be adapted to current usage requirements. Wider pedestrian and cycle paths were to be added. However, the existing bridge cross-section was not sufficient for this, which is why the caps had to be widened accordingly. They began on the (eastern) bridge section A upstream of the Elbe. This was the first time that carbon concrete was used in large bridge construction. The non-metallic carbon reinforcement in combination with concrete opened up new possibilities for bridge renovation as a lighter and more flexible material composite compared to reinforced concrete. The material made it possible to widen the footpath and cycle path from 3.60 meters to 4.25 meters. With conventional materials this would not have been possible for static reasons. In cooperation with the TU Dresden, carbon concrete was to be established in construction. The use on the Carola Bridge was a pilot project that was intended to illustrate the advantages of non-metallic reinforcement and to highlight Dresden as a location for innovation. In addition to carbon concrete, the installation of basalt reinforcement was also to be tested. It was planned to build the bridge cap of arch A from one bank to the middle of the bridge with carbon concrete and the second half to the other bank with basalt concrete.[27][28] The renovation lasted until June 2021 and, in addition to the widened caps, also received new sealing and road equipment as well as a new road surface. In addition, damaged areas were repaired and the drainage was repaired. The cost of bridge section A was around six million euros. From October 2022 to June 2024, the middle bridge section B was renovated in a similar way. Unlike the first stage, this had to be done in accordance with the monument protection regulations due to the fact that the bridge had since been placed under monument protection. For example, the outer surface of the reinforced concrete caps, the area visible from below, was given a corrugation, like the old bridge.[2] From January 2025 to the first quarter of 2026, the renovation of bridge section C was planned,[2] which had received the rating "unsatisfactory" (3.0-3.4) in the last main inspection.[29] The plan was to replace the seals, reinforced concrete caps, railings, lighting and the track itself. The hollow box under the road surface was also due for renovation, which was largely easy to walk on at a height of 1.6 to 5.2 meters. The author Peter Hilbert wrote about it on August 14, 2024: "There are many damaged areas in the concrete with cavities and cracks," which are to be demolished with pneumatic hammers and finally replaced with special mortar, as in the other bridge sections.[2] The tender had already been issued and was canceled after the partial collapse.[30] According to the head of the Institute of Concrete Structures at the TU Dresden, Professor Manfred Curbach, the bridge had been under constant structural monitoring for many years. However, no measurements indicated the impending collapse.[31]
Wonder what if any trends were evident in the satellite data for the bridge that failed in Rhode Island? Would Surfside condominium collapse show any trends? Would Palos Verdes land slippage trends show up over the years? PS - Iceland is using the satellite data to estimate the megatons of lava from each of the current series of volcanic eruptions
Have sent your video to the authorities. Hopefully they will look into it and establish better practices. Wondering why they're not doing it by default.
Live nearby, one of the big problems atm is the road underneath running east-west (southern bank) has also been closed as it runs underneath all 3 spans (the collapsed one that is in the process of being removed as well as the other 2 spans carrying road traffic). The remaining east-west roads are seemingly constantly backed up with traffic.
There's data and there's information - data on infrastructure needs to get converted to useful information. What are the odds that at least 1% of our infrastructural has movements outside the safe design envelop? Good video, thanks.
Did you take into consideration that at the time of the atypical movement (Oct. 2022) the renovation of the middle part (B) of the bridge started? It is connected to the collapsed part C with one connection in the area you called (1) in your video.
Good project for IT grad students. The data is there, all is needed is to integrate that data into an app wherein one could select areas for inspection, specifically bridges.
As a Dresdener, thank you for this very interesting information about InSAR. May I add that the other three historic bridges in the city center are arch bridges from 1852, 1877 and 1910 and still standing strong. We should go back to classic arch designs for bridges. Sturdier and more beautiful.
@@uploadJ I'm not sure what you're getting at, but there is no perfect bridge. In any case, a bridge that shows its damage is better than a bridge that simply collapses without warning.
@@GrandTheftChris LOOK at the Roman coliseum, and tell me what is wrong with that structure? How many years has it stood? Now let's look at the Patheaon (128 BC): WHAT do you see there?
Dear Casey, This just highlights that these important infrastructure assets are now coming to their life’s end, this is compounded that in 1971 i bet no design anticipated the traffic growth and weight it would eventually be subjected to
I live in middle TN, looks like you now have a lifetime of infrastructure material to explore. One of the more interesting imminent dam failures was the warnings about the Nolichucky dam. The initial videos of the overtopping looked eerily similar to the Rapidan dam videos. It was bypassing the dam on the shore, what looked like similar scouring potential. It survived, probably due to the rock embankment, have not seen a video of the dam after the water receded, it may not be there yet. Similar age dam, built in 1930, assume part of the larger TVA project. The other disaster that did happen was the flooding of the new Unicoi hospital where they had to rescue staff and patients from the roof. Seeing drone footage post flood it was obvious that the hospital was in a direct path for a flood, there was a gentle S-curve meander in the river’s path just upstream of the hospital, but above that was a gun barrel straight section of river aimed directly at the hospital. Makes you wonder who would put a hospital in such a comprising position.
Hey, would love a review on possible (lack of) integrity of the Elbe bridges in Hamburg "Elbbrücken" is the name and there are multiple multi rail track and car bridges. I've recently read in the newspaper that they are in need of maintenance but they didn't disclose any details :/
You mentioned monitoring and instrumentation, these have just got really cheap to implement in the last five years. Most of these new sensors are battery powered and radio back to a radio gateway and an off site server, which can then be interrogated by a web portal. The gateway often needs a power supply but we have lamp posts everywhere. A different industry, but we are using the same radio server infrastructure for weather monitoring, bearing temperature, water level sensing, independent plant fault monitoring... Much cheaper than installing cabling, or even modifying the existing computer control systems.
Wow!! Really like your Pirate Bunny shirt, Rabbit n Cross Bones feels truly Long John Silver style. Ace, like the cut of your jib me 'earty, oh arrr, Jim Lad!!! Ref the application of remote monitoring of major infrastructure via satellite, this is the future, and you were first to present this to the world. Fame beckons!!! Brilliant stuff!! I knew that the detailed analysis of civil engineering was crucial, which is why I subbed a year or so ago. Never expected this level of vital data usage!! Thank you
🎯 Key points for quick navigation: 00:13 *Die Warnzeichen für den Einsturz der Corolla-Brücke in Dresden waren seit Jahren vorhanden, basierend auf unabhängigen Satellitendaten.* 00:28 *Der Einsturz ereignete sich am 11. September um **3:00** Uhr morgens, glücklicherweise ohne Verkehr oder Fußgänger auf der Brücke.* 01:09 *Die Brücke, gebaut 1971, bestand aus vorgespannten und nachgespannten Betonelementen, eine gängige Bauweise dieser Zeit.* 01:34 *Daten von ESA-Satelliten zeigen, dass die Brücke bereits vor dem Einsturz in kritischem Zustand war, was auf eine jährliche Absenkung von etwa 24 mm hinweist.* 03:22 *Die Satellitendaten bieten eine hochpräzise Kartierung in allen Wetterbedingungen und sind kosteneffektiv, erfordern aber eine sorgfältige Interpretation durch Experten.* 05:11 *Die Brücke sank etwa einen Zoll pro Jahr ab, während eine benachbarte Brückenseite Anzeichen von Anhebung zeigte, was auf eine Verschiebung des Gleichgewichts hinweist.* 06:46 *Hätten Stadtbeamte diese Daten genutzt, hätten sie die Brücke möglicherweise rechtzeitig für den Verkehr gesperrt und Inspektionen angeordnet.* 09:32 *Die ursprüngliche Corolla-Brücke von 1895 überlebte den Zweiten Weltkrieg, wurde aber 1945 von den Deutschen gesprengt, um den sowjetischen Vormarsch zu verzögern.* 13:18 *Durch den Einsatz von Predictive Analytics könnten ähnliche Brückeneinstürze vermieden werden, indem gefährdete Brücken rechtzeitig identifiziert und überwacht werden.* 16:19 *Deutschland sollte ähnliche Brücken aus der Sowjetzeit identifizieren, Satellitendaten überprüfen und gegebenenfalls Inspektionen und Überwachungen anordnen.* 17:54 *Die Technologie der Satelliten-Interferometrie bietet eine enorme Chance, zukünftige Infrastrukturkatastrophen proaktiv zu verhindern.* Made with HARPA AI
I'm not exactly calm because we also have several bridges in bad condition in my country. Most of them don't have monitoring systems installed, and, although they inspect the bridges frequently, they use outdated methods. There's no money for maintenance, renovations are often 20-30 years late, and our best experts are abroad.
Casey, to be clear, you are suggesting the use of InSAR and other technologies with predictive analytics to augment current conventional bridge inspection. That was my understanding of your video. Did I understand it correctly? I state this because I fear that some views are thinking of predictive analytics as a way to reduce the costs and impacts of bridge inspection. (In the distance future this could be a valid use of predictive analytics.)
Movement is only one inspection parameter. One, which if it shows irregularities, can serve well as a early warning system to trigger more in dept inspections. But the InSAR can't see if a critical steel member is almost corroded through (if it doesn't sack). While any inspector would easily see it. Of course if authorities do take things seriously, the will trigger in dept and special inspections at the slightest hint of potential trouble. In 2007 the swiss authorities had the military run two Main Battle Tanks up and down a critically important viaduct, so the engineers got better data on deformation under a heavy localized load. Everything turned out to be in the green.
I wonder what this data would look like for the Millennium Tower with all off the work that has been done. Seems like I haven’t seen much recent data on the success or failure of the countermeasures that were put in place.
The bridge was constructed in the 1970s (as you reported). It was subject to corrosion, as salt used to melt snow in the winter got into the concrete and affected the reinforcement in the bridge. They new about this for years, yet they squabbled over it for years and only fixed the bridge for cars, as cars are way more important than pedestrians or tram users. They wanted to address the issues next year. They knew about the situation in great detail. They had monitored ist, but they didn't saw the necessity to do something about it. We have similar issues with other bridges in Germany and politicians rather built new highway and fix old ones. So another bridge almost collapsed two or three years ago and had to be blown up in a controlled manner before it collapses. If find is super interesting that you can get such information from InSAR data. Thanks for the input.
One of the contributing factors, at least in my view, might have been corrosion of the prestressed rebar in the upper section of the beams. The corrosion was caused by the heavily use of salt in deicing fluids during low temperatures over many years. Flouride corrosion does not expand hence there was no significant indication of damage at the surface.the prestressed rebars failed, the beam had lost its compression, got tension instead and broke up.
Great video - in particular as it would allow to really apply learnings to other similar bridges. Still, there are only a view graphs provided by value.space and the curves itself are not named. Any chance to release the full report you recieved? Also, did they take into account that the the other 2 briges have been renovated during these years 2022 to now? Thank you very much in advance!
Thanks for the update, Casey Jones! Wow. Hindsight is 20/20 they say... But insight--that's another thing entirely. This kind of data is also publicly available thru the USGS Landsat program, with tools to help make the data useful and understandable for members of the public.
Casey, we establish control points over settlement plates when doing preloads . Why doesn’t the municipality have control points on these bridges to monitor trends in settlement and or sag ?
I would take the satellite data with a grain of salt unless it can be corroborated by other means. It seems to me that if the bridge had sagged several inches over a short time that other signs would have been apparent. Things like cracks, ponding during heavy rain, tilt of light poles, etc. If it was dripping nearly an inch a year for several years, it is really hard to believe that this went completely unnoticed.
According to the data shown, only since 10.10.2022, so little less than 2 years and the total drop was less than 4 inches. that is not necessarily obvious. about 40 mm down and 200m away 40mm up. that is a change in gradient of 0.004 %. that is well below what we notice.
@@LTVoyager It should be noted that the bridge was under re-construction during this time so those factors might have gone unnoticed due to work constantly being performed. I also wonder if perhaps changes in thickness of the new covering might account for some of the differences.
@@CjqNslXUcM The surface sure looks impermeable to me in the pictures available. It looks like concrete on the side with the two rail lines an asphalt on the side with the bike/pedestrian lanes. Most rail bridges are flat or nearly so with slight crown to allow water to run to the sides. Generally, there is a drain under the railings every 100’ or so to drain the water off the bridge. Add in even two inches of sag between the drains and a lot of water will pond during a heavy rain.
Another precise video episode that provide not only data but engineering knowledge. Thanks again Casey. Does predictive analytics provide sufficient resolution to determine the deficiencies between original design errors and those failures related to deferred in-service maintenance?
I was shocked when I found out this occurred in Germany. It just goes to show that infrastructure all over the World is at risk, and for a myriad of reasons.
The reason here is, that the german government priotises everything, exept the things benefiting the native population. An example: When we hat a massive flood that unalived ~110 people, aid money to rebuild the local infrastructure was still not comming 1 year later, while at the same time, germany spent millions to rebuild flood damage in pakistan.
The reason here is, that the german government priotises everything, exept the things benefiting the native population. An example: When we hat a massive flood that unalived ~110 people, aid money to rebuild the local infrastructure was still not comming 1 year later, while at the same time, germany spent millions to flood rebuilding efforts in asis (p...istan).
Let's not forget that this bridge was built when this part of Germany was under Russian rule. This bridge was on a list to be replaced soon. The city is and was busy with a number of other bridges. You just can't do everything at once.
It is not the first nor the last bridge in Germany, that will collapse. Most bridges that were build right after WW2 (many!) are now at an age they need replacement.
What incredible technology! Measuring millimetre-scale variations from orbit. And some simple(?) but clever analytics to get a nice signal. Great potential. A pity that the danger sign was there for so long, but unnoticed.
Pre-stressed or Post Tension assemblies solve a lot of issues, but not without some down sides. I've encountered many cable ends that were not properly sealed. Many times the use of a torch to cut the excess leaves a lot of slag, or too much cable behind, which prevents the caps from being properly installed allowing water intrusion. I know there are other ways to prevent water intrusion besides caps.
10:25 The demolition doesn't impede the forensic analysis of the collapse - they only demolished the spans which didn't collapse initially to make room for the flood event. The one collapsed span in the navigation channel is untouched.
3:30 Probably cost effective without the shadow of a doubt BUT what about the health of living beings on earth? How does this radar signal affect our health?
Since no bodily harm whatsoever occurred, rebuilding the bridge as soon as possible takes precedence over careful forensic investigation. This was a conscious decision. The investigation whether neglect and/or misconduct was at work is not affected by this.
Note that the span that was hastily torn down was not the failed span but the adjacent one. It was sagging like a banana, so it had to come down in a controlled manner, as there was the danger of it coming down by itself and bringing down the rest of the bridge with it. Not what you want when a flood is approaching...
In the case of bridges, the cause of deflection can be a payload? Couldn't the deviation in the measurements be caused by the change in the load at the time of the measurements?
Good video. Reinventing the wheel is such a waste but, I've seen an oganization that reinvents the square wheel about every decade(corruption is involved). Does Germany use road salt? The usual problem is that politicians don't want to spend the money for proper maintenance of roads and bridges. Good Luck, Rick
Thank you. Reports suggest that they do use road salts, but just like in the U.S., local media are thin on reporting details. I will keep digging on this story though.
The former GDR was very generous with road salt, as is well known. So the bridge could have been exposed to a lot of salt, at least in the first 18 years of its existence. Investigations are already underway into whether a certain lamp post on the bridge could have been a gateway for the salt to enter the internal structures. And no, the maintenance was not neglected by politicians with their eyes wide open, but after reunification we (West Germany) had to bring a whole third world country (East Germany) and its rotting infrastructure, economy, environmental damage, workforce and social system up to scratch as quickly as possible. We have spent literally hundreds of billions on this over the last 30 years. East Germany today is cleaner and more beautiful than large parts of West Germany. But in this huge undertaking, which included keeping the existing western economy running to finance it all, some things may have been overlooked or postponed. This should come as no surprise to anyone. PS: The bridge has been under repair since 2019 already, but only the part that is still standing has been completed so far. The collapsed part would have been next.
Typical winter climates in Germany have thaw-freeze cycles, so we use road salt. On bridges you need quite a lot as they are completely exposed to the atmosphere.
@@hape3862 No, I'm sorry, but that's nonsense. Net investment in infrastructure in Germany has been around 0 since ~1998, so we have invested virtually nothing in the last 30 years and it shows. We have thousands of bridges that need to be replaced, our rail infrastructure is so old and obsolete that we will not be able to run an integrated timetable until 2070 - something Switzerland has had since 1982, and so on. Economy institutes in Germany estimate that we have an infrastructure defecit of 700 billion Euros, and it is getting worse because of the "debt break". This was a deliberate choice and it is now costing us dearly.
Hi everyone, i have a question to the uplift detection method with the help of inSAR data. Are there ground-based measurements that allow the method to be validated? How is the traffic load on the bridge corrected during the recording of the inSAR data? I guess this factor has also an impact on the bridge movment....
It seems like these scanning companies should be offering a civil service package where a municipality could give them a list of critical infrastructure, and "if it moves, call us" This is one reason why I'm hype for the future of comercial space, they are making it possible that this kind of tracking on an affordable scale. It's such a new concept that they have the data and don't even know what to do with most of it
Please cover the Lake Lure dam failure, Rutherford Cty. NC, predicted to occur soon , September 27, 2024, due to flooding from the recent hurricane Helene.
It’s amazing the satellite can measure so accurately and we can draw any useful inferences from it, because pedestrians and trains over the bridge would naturally change the “height” of the bridge massively on different passes.Did they just measure a handrail or something?
When people question the wisdom of spending money on space-based technology, especially “mission to planet Earth”, it is things like this that can answer in concrete terms (pun intended). Thank you for your reporting. Please keep up the great work.
How does the analysis of the satellite data account for the roadworks, that were ongoing on the bridge for the last years? They extended its width for pedestrians with new carbon concrete and renewed the road surface on both sides, during which time they removed the old road surface. The satellite data approach sounds promising though!
Surprising there isn’t a site that will interpret the data on maps. There is so much this could be used, such as glaciers, landslide, erosion, earthquake impacts..the list is endless.
Thank you. Yes, I think it could at some point. You are basically having to deal with massive amounts of data so a well-trained A.I. should be able to identify target areas of concern early on.
What does the InSAR data say about the closed bridge in Rhode Island and what about the various bridges constructed with T1, ASTM A514, Steel which have experienced Hydrogen embrittlement ? Can the effects caused by cracks from Hydrogen embrittlement be detected by InSAR observations ? If so, this may be an efficient means to evaluate structures prior to any need for closure or potentially allow early remediation.
maybe engeneers around the wold may ask for analysis of specific objects in future to check. Oh could they check the building collapse in Miami/Florida if there are meassurepoints available too?
Anybody responsible for safety and maintenance of infrastructure like bridges should be able to access this information, at little or no significatn cost. It ought to be as routine as inspections, and much more frequent.
Every video is addictive and fascinating. I’m in Omaha and it’s scary to think about the two most used bridges across the Missouri River which we use to travel I-29 north and south as well as I-80 east. There are many bridges where we can see the steel frame and most show corrosion some awful. The farther north the more salt. As a younger man we traveled I-35W bridge which collapsed some years after we last traveled that to and from Duluth Mn
In the UK, road bridges are typically designed to last 100 years. We have a lot of bridges in Europe, you don't want to be rebuilding them all every 50 years.
Could these type of failures be caused by fatigue failure? Maybe more so in concrete. Maybe related to distance from pilings and distance between pilings. Possibly related to a section in which there is a slight up and down bending. One side of the breakage is more anchored than the other side of the breakage. There is more leverage on one side than there is in the more anchored side.
thank you once again. your point of how western economies must pony up and fix or replace the necessary is spot on. it is not about spending it is all about investment.
I managed to garble the description of InSAR terms in the video. Here is the correction ● Overview- Interferometric Synthetic Aperture Radar (InSAR) is a remote sensing technology used to measure ground surface deformation with high precision. It works by comparing radar signals from two or more passes of a satellite or aircraft over the same area. By analyzing the phase difference between these radar signals, InSAR can detect minute changes in the Earth's surface over time.
So would any city, anywhere in the world, be able to look up satellite information for their area?
next...... railway bridge closed !!
Die Eisenbahnbrücke in Radeberg ist ab sofort voll gesperrt. Die Brücke hatte bei der regulären Untersuchung im August die Zustandsnote 3,5 erhalten. Das gilt beim Brücken-TÜV als ungenügender Bauwerkszustand. Seit dem Einsturz der Carolabrücke in Dresden sind Behörden deutschlandweit für die Zustände ihrer Brücken sensibilisiert.
@@pozzee2809 Yes, absolutely unless the road is located in Area 51!
@@CaseyJones-Engineer 😂
@@SteppingR They are aware of it for at least the last 10 years. I'm living on the A45 (Sauerlandlinie). There are more bridges than road segments on this highway. All with pretty much same age as Carolabrücke and most are reconstructed or in the process. It's a continous construction site for at least the last 10 years.
One miss of @CaseyJones-Engineer is that Carolabrücke was already under supervision of Technical University Dresden. So the experteese was obviously already top notch. The other side of the bridge was already reconstructed. The failing side due to for next year. So a highly unlikely timing.
Whats still myseriously is that it collapsed empty. It's used continously for the tram. These vehicles are relatively heavy.
So a construction near collapse would have been expected to collapse with this heavy load on top, not empty, minutes after the last tram.
@xxxy9928 in case of Deutsche Bahn (DB) it was more the problem that maintainance was the responsibility of DB, while new construction is fedral responsibility. So maintainance was intentionally cut by DB to save money and move the reconstruction cost to federal budgets.
The bridge had monitoring equipment placed on it, and it was known it was failing, that's why it was supposed to be replaced, but the monitoring did not predict an imminent failure. Problem with the kind design from that era is that, unlike today, it was built without any means to inspect the tension cables and measure their load. It is also a well known problem and affects also bridges in West, and we have a number of these bridges in Berlin, mostly train bridges, and they are all in the process of being completely replaced. Also, German bridges are built with 100 years intended life time, and these tension concrete bridges are now being replaced with completely different types of bridges that do last longer than 50 years and can be better inspected and repaired.
It was abput to be replaced but analysis a few months prior indicated that it was no risk.
The high temps during the summer probably pur it under stress and the the sharp drop in temps caused it to fail.
The biggest problem in these cases in Europe is the bureaucracy. The bridge fell before all architects, preservationists, nature activists, amateur architects among citizens, and politicians finding a way how to get the contract for his brother's company got to an agreement.
It was not to be replaced, the renovation was scheduled for 2025, the other parts of the bridge were renovated the prior years and now they have to write off those costs, coz they also have to be torn down.
In coming 30 years Germany will basically have to replace all of its bridges. How will they fund this?
@@mipmipmipmipmip-v5x all? Where did you get that information from?
Your channel is popular because it is interesting, professional and honest with no sensationalism for clicks. It would be interesting to look back at historic images of the Millennium Tower in San Fransisco to see any movement and whether it correlates with that reported.
The city officials in Dresden were well aware of the problem prior to the incident. They dont need satellite data to know that there is a problem - those bridges are inspected on the ground, in frequent intervals. They knew that the bridge was damaged, and some repairs have been done on the other side. More repairs were planned to happen soonish. Too late for that now. The bridge will be completely demolished and a new one build.
You see, this is not a isolated incident. We have about 7000 bridges in Germany that were build from reenforced concrete during the 50s, 60s and 70s, as a reaction to the economical boom after WW2. That happened in West Germany as well as in the former communist GDR, where Dresden is located.
Unfortunatly politics have neglected to take the neccessary steps to maintain this infrastucture in a proper way and rather spend the money on other things.
I'd bet this won't be the only bridge that collapses in the coming years. And it won't always happen at 3 am, when nobody is around.
Afaik the other sides more or less got new tarmac only. Nothing was done to the supporting structure
I'd trust a bridge in East Germany as much as I'd trust a bridge in Russia.
These post Soviet places are rotten to the core with corruption and corner cutting.
The people there still have no pride in community or society.
Es ist kein Geld da für einen Neubau, das ganze Geld fließt in die Ukraine. Stand in den Zeitungen, Sächsische Zeitung zum Beispiel.
@@benteyssen5720 Ich habe meine Zweifel, dass das in der SZ stand.
@@toi_techno That's of course utter BS on all levels.
These satellite images are very useful here in Iceland to monitor magma accumulation on the Reykjanes peninsula.
As a German being surprised by the algorithmen to suggest me the video, VERY GOOD! Thank you.
Great video, very informative. I can't believe how lucky they were that no traffic was on it when it fell.
In a way that monitoring already exists. There's the "Bodenbewegungsdienst Deutschland" ("Ground movement service Germany"), a part of an European project of all countries that participate in the Sentinel mission. It's specifically tasked to use this exact data to monitor the countries for ground movements (landslides, sinkholes, mine shaft collapses, etc), and does not look at bridges and the like. They have a freely available web portal (I'll try to link it in a reply to this comment). Unfortunately, unlike the commercial provider, they exclude bridges for the most part. But it should be (more or less) straightforward to expand that project to infrastructure!
You still have to attach and assign those data sets to teams and humans working on it.
Thank you very much for this interesting video.I'm a Dresden resident and really appreciate such good and useful information.
@@AnitramE Thanks for watching!
There was a TV program years ago called Person of Interest. A super dooper supercomputer monitoring phone calls and CC TV cameras noticed individual behavior and predicted upcoming crimes. The hero was able to intervene on the side of the good guys. Ridiculous, right?
This video left me wide eyed. Predictive analytics! Wow! Now all we need are heroes who will do something with the data in time!
Great video! Thanks, Casey. 👍🏻👏
POI was the best network tv show this century.
@@Michael_K_Woods god damn was that a good tv show. i watch i once a year, i think its my favorite tv show. it was WAY ahead in predicting things.
The predictive data didn't come from analysis of dreams from hairless people asleep in a milk bath?
Loved that show. I don't know how such a good show got greenlit. The management must have been asleep at the switch.
Interesting...I've not watched tv shows now for more than a decade, but as a precursor to that show were the excellent films, "Brazil" (1985), "Enemy of the State" (1998) and "Minority Report" (2002).
Just to make clear how close this collapse was to a disaster: In the moment of the collapse there actually was traffic on the bridge, just not on the part that fell into the Elbe. There is video footage that shows a car driving over the bridge when it collapsed. The last Tram passed only 3 minutes before the collapse. We were really lucky here.
I have crossed that bridge countless times myself, it is quite a strange feeling to think about the bad shape it was in. Just a few weeks before the collapse there was a concert on the banks of the river. The bridge section that collapsed was filled with people - from what I've heard they were even standing on the Tram tracks. It is horrifying to think what could have happened...
This is awesome, bridge inspection from space.
I didn't know this technology had been deployed already. I hope you can get a look at the Millennium Tower data. Thank You, this will open up a whole new world of research.
It's a short story about how interesting consecutive data is. While the long story needs to include the very limits: (1) the correlation to temperature was done, (2) the correlation to the river level was not done but could be done, (3) there was intense work done on other parts of the bridge, which includes changed traffic and changed loads by that, also caused by modyfied building materials, modified road surface next to the destroyed bridge part (also different loads on the foundation)...
A technical detail, the three parallel bridge spans were interlinked in some places. The collapsed bridge span tore down the adjacent parallel span by 17 cm (almost 7 inches) before the interlink there broke. The bridge is closed for traffic indefinitely and probably will be demolished completely.
Well made and informative video! Greetings from Dresden Germany! ;)
Thank you!!
Sharp analysis. Excellent report.
Thank you!
For the InSAR data, it's worth considering added radar reflectors (passive & cheap!) to the structures to create defined sensing points, rather than just accepting the overall 'average' motion that classic InSAR of the generic 'ground' will give.
Alternates are to get a dedicated 'stealth' analysis of the radar reflection, given that SAR isn't a direct overhead look, rather it's a sideways look, with trigonometry to determine height shifts.
So all the 'stealth' calculations make exactly the same predictions, with an opposite purpose. Here we want to 'see' particular aspects of the structure, rather than hide the structure ;-)
Vielen Dank für dein Video! Ein wirklich gutes Beispiel für das gesellschaftliche Lösungspotential von Internet und Satellitentechnik.
Thank you very much for your video! A really good example of the social solution potential of the Internet and satellite technology.
lol I'm seriously having a 'nerd attack' over what that satellite can do! I had no IDEA this was possible! Wow!
😂
predictive analytics would be (outstanding) smart for ca. 1000 bridges in BRD , which are already behaving with cracks , corrosion or preparing for decay.
And remarkable that the data is available to us.
@@chriss.9060 A thousand bridges?
Thanks!
Thank you very much!
What a phenomenal resource - almost real time monitoring and predictive analysis tool.
I have found iver years if work with state government entities that most often, the process is to get something built. Let the next administration worry about the maintenance, even if that's a consideration. And, even if the money is built into the budget for preventative maintenance, oftentimes, it's gobbled up by another immediate need. Basically, like a deck of cards, nothing happens until a collapse. Once something starts to fail, it all collapses, and then fingers begin wagging.
Over the years I've noticed that one particular party refuses to pay maintenance so they can complain when the other party comes into office and spends money on maintenance. As well as taking money out of a budget because it was earmarked for emergencies. Pennywise,😢 pound foolish. At the city and state level.
As well as refusing to recognize the cost of maintenance when bragging about putting up a new building, justified by the expense of maintaining the old building.
This bridge was up to refurbishment but not considered extra urgent. They got surprised by the collapse. A sign that they need to think about better monitoring methods. The ones they used obviously did not tell them what they needed to know.
The bridge complex was already in the process of refurbishment since 2022, with the partial bridge carrying motor vehicles having been finished - the tram bridge that collapsed was the part planned to be refurbished next.
the bridge was hard to check on due to poor design choice, so they didn't really know for sure
still a bit reckless to allow transit before the refurbishment was completed if they had no means to know for sure whether or not the bridge was about to collapse
There’s a bridge known as the steamboat Slough bridge located in northern California near Sacramento. It’s a bascule type bridge that was built in the 1920s. Over the last 20 or 30 years it has been moving closer together. Caltrans is the owner and they keep cutting the steel to make the bridge to adjust the gap to make it operational. but to my knowledge they haven’t identified the cause of this problem. Maybe this type of data could be helpful in this situation?
California? Maybe it's continental plates moving below?
@@jannikheidemann3805 haha maybe
Wall I can say is holy shit! I’m retired now but I can see huge engineering potential in so many fields. Maybe even pipeline failure.
Thanks! New tech
Thank you so much!
This was fascinating - I sent the link to our IT guy who is leading our AI/data section. Not sure about usage (yet) - but things keep going forward - hmmm - can you get the same data from the Teton landslide - maybe they can show first how long the land was moving - and second you probably could model the construction work being done to make sure that they don't build it up too fast? Many ideas wandering through my head now - need more coffee to organize them.
Thank you. I am working on obtaining data for Teton Bypass and other projects that I have covered. I think there is a lot of potential here with this technology.
Have a look at this here too: The European Gound Movement Service uses the Sentinel data to monitor countries for risk of landslides, sinkholes, mine cave-ins and things like that. I suppose a module to monitor bridges and other infrastructure could easily be added into their analysis pipeline once it's worked out.
Just wanted to tell you that I absolutely love your videos❤️. Thanks from Kearney, MO!!!!
@@fly3po1 Thank you so much!!
Very Professional engeneering your doing here. But you might want to check the german Wikipedia article to see if it is also only a stup.
It changed quite a bit since the collaps but it is in renovation since 2019.
Renovation work from 2019
Carola Bridge, looking towards Neustadt (2020)
Prefabricated parts made of carbon concrete for the widening of the Carola Bridge
Repair work on the Carola Bridge in June 2020. Prefabricated parts made of carbon concrete are used to widen the pedestrian and cycle paths
Although the bridge's supporting structure appears to be in good condition, the author Peter Hilbert admits: "The Carola Bridge has suffered considerable damage over the decades."[2] Therefore, the renovation work began in November 2019. In addition, the roadway equipment and design were to be adapted to current usage requirements. Wider pedestrian and cycle paths were to be added. However, the existing bridge cross-section was not sufficient for this, which is why the caps had to be widened accordingly.
They began on the (eastern) bridge section A upstream of the Elbe. This was the first time that carbon concrete was used in large bridge construction. The non-metallic carbon reinforcement in combination with concrete opened up new possibilities for bridge renovation as a lighter and more flexible material composite compared to reinforced concrete. The material made it possible to widen the footpath and cycle path from 3.60 meters to 4.25 meters. With conventional materials this would not have been possible for static reasons. In cooperation with the TU Dresden, carbon concrete was to be established in construction. The use on the Carola Bridge was a pilot project that was intended to illustrate the advantages of non-metallic reinforcement and to highlight Dresden as a location for innovation. In addition to carbon concrete, the installation of basalt reinforcement was also to be tested. It was planned to build the bridge cap of arch A from one bank to the middle of the bridge with carbon concrete and the second half to the other bank with basalt concrete.[27][28] The renovation lasted until June 2021 and, in addition to the widened caps, also received new sealing and road equipment as well as a new road surface. In addition, damaged areas were repaired and the drainage was repaired. The cost of bridge section A was around six million euros.
From October 2022 to June 2024, the middle bridge section B was renovated in a similar way. Unlike the first stage, this had to be done in accordance with the monument protection regulations due to the fact that the bridge had since been placed under monument protection. For example, the outer surface of the reinforced concrete caps, the area visible from below, was given a corrugation, like the old bridge.[2]
From January 2025 to the first quarter of 2026, the renovation of bridge section C was planned,[2] which had received the rating "unsatisfactory" (3.0-3.4) in the last main inspection.[29] The plan was to replace the seals, reinforced concrete caps, railings, lighting and the track itself. The hollow box under the road surface was also due for renovation, which was largely easy to walk on at a height of 1.6 to 5.2 meters. The author Peter Hilbert wrote about it on August 14, 2024: "There are many damaged areas in the concrete with cavities and cracks," which are to be demolished with pneumatic hammers and finally replaced with special mortar, as in the other bridge sections.[2] The tender had already been issued and was canceled after the partial collapse.[30]
According to the head of the Institute of Concrete Structures at the TU Dresden, Professor Manfred Curbach, the bridge had been under constant structural monitoring for many years. However, no measurements indicated the impending collapse.[31]
Thank you very much for this very informative Update!👍
Wonder what if any trends were evident in the satellite data for the bridge that failed in Rhode Island? Would Surfside condominium collapse show any trends? Would Palos Verdes land slippage trends show up over the years?
PS - Iceland is using the satellite data to estimate the megatons of lava from each of the current series of volcanic eruptions
Have sent your video to the authorities. Hopefully they will look into it and establish better practices. Wondering why they're not doing it by default.
One of the ships beneath the bridge actually recorded the incident in realtime.
Its a bit hard to find, but ARD made an online article about it.
It is also here on YT if you search for " CAROLABRÜCKE DRESDEN: Neues Video vom Brückeneinsturz aufgetaucht! I Sachsen Fernsehen"
Live nearby, one of the big problems atm is the road underneath running east-west (southern bank) has also been closed as it runs underneath all 3 spans (the collapsed one that is in the process of being removed as well as the other 2 spans carrying road traffic). The remaining east-west roads are seemingly constantly backed up with traffic.
Thank you for your perspective and the thorough analysis. There was nothing in the German Press about this technology, very sad.
Greetings from Saxony
Thank you! I plan to do other videos featuring this technology.
i think value space might have found a good gig analyzing bridges for authorities
All of your videos are interesting!
There's data and there's information - data on infrastructure needs to get converted to useful information. What are the odds that at least 1% of our infrastructural has movements outside the safe design envelop? Good video, thanks.
and handed out to people that can change something ;P
You did a good job of explaining the InSAR measurements despite the small misstatement of what InSAR stands for. This is my area of expertise.
Thank you!
Greetings from Saxony! Love your content. Keep the good work up.
Thank you!
Did you take into consideration that at the time of the atypical movement (Oct. 2022) the renovation of the middle part (B) of the bridge started? It is connected to the collapsed part C with one connection in the area you called (1) in your video.
He did not. Because he has no clue.
Good project for IT grad students. The data is there, all is needed is to integrate that data into an app wherein one could select areas for inspection, specifically bridges.
As a Dresdener, thank you for this very interesting information about InSAR. May I add that the other three historic bridges in the city center are arch bridges from 1852, 1877 and 1910 and still standing strong. We should go back to classic arch designs for bridges. Sturdier and more beautiful.
A 'fail safe' design versus fracture critical design?
@@uploadJ I'm not sure what you're getting at, but there is no perfect bridge. In any case, a bridge that shows its damage is better than a bridge that simply collapses without warning.
@@GrandTheftChris LOOK at the Roman coliseum, and tell me what is wrong with that structure? How many years has it stood? Now let's look at the Patheaon (128 BC): WHAT do you see there?
@@uploadJ What I see is apples and oranges.
@@GrandTheftChris re: " I see is apples and "
Typical response by a member of the public.
I would never have guessed satellite Radar mapping could measure bridge deflection. It opens up a whole new field of structural analysis.
10:52 where did they get these temporary supports, Harbor Freight? 😬
Dear Casey, This just highlights that these important infrastructure assets are now coming to their life’s end, this is compounded that in 1971 i bet no design anticipated the traffic growth and weight it would eventually be subjected to
Thanks for the information 👏 💖
I live in middle TN, looks like you now have a lifetime of infrastructure material to explore. One of the more interesting imminent dam failures was the warnings about the Nolichucky dam. The initial videos of the overtopping looked eerily similar to the Rapidan dam videos. It was bypassing the dam on the shore, what looked like similar scouring potential. It survived, probably due to the rock embankment, have not seen a video of the dam after the water receded, it may not be there yet. Similar age dam, built in 1930, assume part of the larger TVA project. The other disaster that did happen was the flooding of the new Unicoi hospital where they had to rescue staff and patients from the roof. Seeing drone footage post flood it was obvious that the hospital was in a direct path for a flood, there was a gentle S-curve meander in the river’s path just upstream of the hospital, but above that was a gun barrel straight section of river aimed directly at the hospital. Makes you wonder who would put a hospital in such a comprising position.
I did predictive analytics for 10 yrs now I’m interest in looking at that data
Hi Casey, I have a photo taken 3 days before the collapse confirming these deflection increases. How do I send it to you ?
Hey, would love a review on possible (lack of) integrity of the Elbe bridges in Hamburg "Elbbrücken" is the name and there are multiple multi rail track and car bridges. I've recently read in the newspaper that they are in need of maintenance but they didn't disclose any details :/
You mentioned monitoring and instrumentation, these have just got really cheap to implement in the last five years. Most of these new sensors are battery powered and radio back to a radio gateway and an off site server, which can then be interrogated by a web portal. The gateway often needs a power supply but we have lamp posts everywhere.
A different industry, but we are using the same radio server infrastructure for weather monitoring, bearing temperature, water level sensing, independent plant fault monitoring... Much cheaper than installing cabling, or even modifying the existing computer control systems.
Wow!! Really like your Pirate Bunny shirt, Rabbit n Cross Bones feels truly Long John Silver style. Ace, like the cut of your jib me 'earty, oh arrr, Jim Lad!!! Ref the application of remote monitoring of major infrastructure via satellite, this is the future, and you were first to present this to the world. Fame beckons!!! Brilliant stuff!! I knew that the detailed analysis of civil engineering was crucial, which is why I subbed a year or so ago. Never expected this level of vital data usage!! Thank you
Awesome, thank you! There will definitely be more to come on this technology being applied in future videos.
🎯 Key points for quick navigation:
00:13 *Die Warnzeichen für den Einsturz der Corolla-Brücke in Dresden waren seit Jahren vorhanden, basierend auf unabhängigen Satellitendaten.*
00:28 *Der Einsturz ereignete sich am 11. September um **3:00** Uhr morgens, glücklicherweise ohne Verkehr oder Fußgänger auf der Brücke.*
01:09 *Die Brücke, gebaut 1971, bestand aus vorgespannten und nachgespannten Betonelementen, eine gängige Bauweise dieser Zeit.*
01:34 *Daten von ESA-Satelliten zeigen, dass die Brücke bereits vor dem Einsturz in kritischem Zustand war, was auf eine jährliche Absenkung von etwa 24 mm hinweist.*
03:22 *Die Satellitendaten bieten eine hochpräzise Kartierung in allen Wetterbedingungen und sind kosteneffektiv, erfordern aber eine sorgfältige Interpretation durch Experten.*
05:11 *Die Brücke sank etwa einen Zoll pro Jahr ab, während eine benachbarte Brückenseite Anzeichen von Anhebung zeigte, was auf eine Verschiebung des Gleichgewichts hinweist.*
06:46 *Hätten Stadtbeamte diese Daten genutzt, hätten sie die Brücke möglicherweise rechtzeitig für den Verkehr gesperrt und Inspektionen angeordnet.*
09:32 *Die ursprüngliche Corolla-Brücke von 1895 überlebte den Zweiten Weltkrieg, wurde aber 1945 von den Deutschen gesprengt, um den sowjetischen Vormarsch zu verzögern.*
13:18 *Durch den Einsatz von Predictive Analytics könnten ähnliche Brückeneinstürze vermieden werden, indem gefährdete Brücken rechtzeitig identifiziert und überwacht werden.*
16:19 *Deutschland sollte ähnliche Brücken aus der Sowjetzeit identifizieren, Satellitendaten überprüfen und gegebenenfalls Inspektionen und Überwachungen anordnen.*
17:54 *Die Technologie der Satelliten-Interferometrie bietet eine enorme Chance, zukünftige Infrastrukturkatastrophen proaktiv zu verhindern.*
Made with HARPA AI
I'm not exactly calm because we also have several bridges in bad condition in my country. Most of them don't have monitoring systems installed, and, although they inspect the bridges frequently, they use outdated methods. There's no money for maintenance, renovations are often 20-30 years late, and our best experts are abroad.
Casey, to be clear, you are suggesting the use of InSAR and other technologies with predictive analytics to augment current conventional bridge inspection. That was my understanding of your video. Did I understand it correctly?
I state this because I fear that some views are thinking of predictive analytics as a way to reduce the costs and impacts of bridge inspection.
(In the distance future this could be a valid use of predictive analytics.)
That is right. This data analysis would be a supplement and not a replacement for routine or special bridge inspections.
Movement is only one inspection parameter. One, which if it shows irregularities, can serve well as a early warning system to trigger more in dept inspections.
But the InSAR can't see if a critical steel member is almost corroded through (if it doesn't sack). While any inspector would easily see it.
Of course if authorities do take things seriously, the will trigger in dept and special inspections at the slightest hint of potential trouble. In 2007 the swiss authorities had the military run two Main Battle Tanks up and down a critically important viaduct, so the engineers got better data on deformation under a heavy localized load. Everything turned out to be in the green.
Danke.
Gern geshehen!
I wonder what this data would look like for the Millennium Tower with all off the work that has been done. Seems like I haven’t seen much recent data on the success or failure of the countermeasures that were put in place.
The bridge was constructed in the 1970s (as you reported). It was subject to corrosion, as salt used to melt snow in the winter got into the concrete and affected the reinforcement in the bridge. They new about this for years, yet they squabbled over it for years and only fixed the bridge for cars, as cars are way more important than pedestrians or tram users. They wanted to address the issues next year. They knew about the situation in great detail. They had monitored ist, but they didn't saw the necessity to do something about it. We have similar issues with other bridges in Germany and politicians rather built new highway and fix old ones. So another bridge almost collapsed two or three years ago and had to be blown up in a controlled manner before it collapses.
If find is super interesting that you can get such information from InSAR data. Thanks for the input.
2:04 InSAR
Interferometric Synthetic Aperture Radar
Wait until the 5G people figure out they are being bombarded with Radar every 28 days.
One of the contributing factors, at least in my view, might have been corrosion of the prestressed rebar in the upper section of the beams. The corrosion was caused by the heavily use of salt in deicing fluids during low temperatures over many years. Flouride corrosion does not expand hence there was no significant indication of damage at the surface.the prestressed rebars failed, the beam had lost its compression, got tension instead and broke up.
Great video - in particular as it would allow to really apply learnings to other similar bridges. Still, there are only a view graphs provided by value.space and the curves itself are not named. Any chance to release the full report you recieved? Also, did they take into account that the the other 2 briges have been renovated during these years 2022 to now? Thank you very much in advance!
Thanks for the update, Casey Jones!
Wow. Hindsight is 20/20 they say...
But insight--that's another thing entirely.
This kind of data is also publicly available thru the USGS Landsat program, with tools to help make the data useful and understandable for members of the public.
Casey, we establish control points over settlement plates when doing preloads . Why doesn’t the municipality have control points on these bridges to monitor trends in settlement and or sag ?
I would take the satellite data with a grain of salt unless it can be corroborated by other means. It seems to me that if the bridge had sagged several inches over a short time that other signs would have been apparent. Things like cracks, ponding during heavy rain, tilt of light poles, etc. If it was dripping nearly an inch a year for several years, it is really hard to believe that this went completely unnoticed.
According to the data shown, only since 10.10.2022, so little less than 2 years and the total drop was less than 4 inches. that is not necessarily obvious. about 40 mm down and 200m away 40mm up. that is a change in gradient of 0.004 %. that is well below what we notice.
@@beyondEV Four inches is hugely obvious when it comes to water runoff and ponding.
@@LTVoyager It should be noted that the bridge was under re-construction during this time so those factors might have gone unnoticed due to work constantly being performed. I also wonder if perhaps changes in thickness of the new covering might account for some of the differences.
Where is it supposed to pond? It's a light rail bridge with a bikelane. It doesn't have a flat impermeable surface
@@CjqNslXUcM The surface sure looks impermeable to me in the pictures available. It looks like concrete on the side with the two rail lines an asphalt on the side with the bike/pedestrian lanes. Most rail bridges are flat or nearly so with slight crown to allow water to run to the sides. Generally, there is a drain under the railings every 100’ or so to drain the water off the bridge. Add in even two inches of sag between the drains and a lot of water will pond during a heavy rain.
That was a very interesting video, thank you! You mentioned that the data is public, where can I get it?
Very informative and instructional video 🙂
Another precise video episode that provide not only data but engineering knowledge. Thanks again Casey. Does predictive analytics provide sufficient resolution to determine the deficiencies between original design errors and those failures related to deferred in-service maintenance?
I was shocked when I found out this occurred in Germany.
It just goes to show that infrastructure all over the World is at risk, and for a myriad of reasons.
The reason here is, that the german government priotises everything, exept the things benefiting the native population.
An example: When we hat a massive flood that unalived ~110 people, aid money to rebuild the local infrastructure was still not comming 1 year later, while at the same time, germany spent millions to rebuild flood damage in pakistan.
The reason here is, that the german government priotises everything, exept the things benefiting the native population.
An example: When we hat a massive flood that unalived ~110 people, aid money to rebuild the local infrastructure was still not comming 1 year later, while at the same time, germany spent millions to flood rebuilding efforts in asis (p...istan).
Let's not forget that this bridge was built when this part of Germany was under Russian rule.
This bridge was on a list to be replaced soon. The city is and was busy with a number of other bridges. You just can't do everything at once.
It is not the first nor the last bridge in Germany, that will collapse. Most bridges that were build right after WW2 (many!) are now at an age they need replacement.
@@NL2500 yeah, but they also skipped doing the load calculations, when they added a bikeway...
What incredible technology! Measuring millimetre-scale variations from orbit. And some simple(?) but clever analytics to get a nice signal. Great potential. A pity that the danger sign was there for so long, but unnoticed.
Pre-stressed or Post Tension assemblies solve a lot of issues, but not without some down sides. I've encountered many cable ends that were not properly sealed. Many times the use of a torch to cut the excess leaves a lot of slag, or too much cable behind, which prevents the caps from being properly installed allowing water intrusion. I know there are other ways to prevent water intrusion besides caps.
The bit that collapsed and fell into the River actually still sits in the River, or at least it did last Friday.
12:44 - Would this approach have revealed the imminent failure of the I-35W bridge in Minneapolis?
Another outstanding and informative presentation.
Oh, love the Psycho Bunny optimism. lol
Thank you Casey 🙏
Thank you! My wife liked those shirts so she picked up a couple for me.
10:25 The demolition doesn't impede the forensic analysis of the collapse - they only demolished the spans which didn't collapse initially to make room for the flood event. The one collapsed span in the navigation channel is untouched.
Most of this technical stuff escapes me, but the point certainly lands loud and clear.
3:30 Probably cost effective without the shadow of a doubt BUT what about the health of living beings on earth?
How does this radar signal affect our health?
Since no bodily harm whatsoever occurred, rebuilding the bridge as soon as possible takes precedence over careful forensic investigation. This was a conscious decision.
The investigation whether neglect and/or misconduct was at work is not affected by this.
Note that the span that was hastily torn down was not the failed span but the adjacent one. It was sagging like a banana, so it had to come down in a controlled manner, as there was the danger of it coming down by itself and bringing down the rest of the bridge with it. Not what you want when a flood is approaching...
In the case of bridges, the cause of deflection can be a payload? Couldn't the deviation in the measurements be caused by the change in the load at the time of the measurements?
Good video. Reinventing the wheel is such a waste but, I've seen an oganization that reinvents the square wheel about every decade(corruption is involved). Does Germany use road salt? The usual problem is that politicians don't want to spend the money for proper maintenance of roads and bridges. Good Luck, Rick
Thank you. Reports suggest that they do use road salts, but just like in the U.S., local media are thin on reporting details. I will keep digging on this story though.
The former GDR was very generous with road salt, as is well known. So the bridge could have been exposed to a lot of salt, at least in the first 18 years of its existence. Investigations are already underway into whether a certain lamp post on the bridge could have been a gateway for the salt to enter the internal structures.
And no, the maintenance was not neglected by politicians with their eyes wide open, but after reunification we (West Germany) had to bring a whole third world country (East Germany) and its rotting infrastructure, economy, environmental damage, workforce and social system up to scratch as quickly as possible. We have spent literally hundreds of billions on this over the last 30 years. East Germany today is cleaner and more beautiful than large parts of West Germany. But in this huge undertaking, which included keeping the existing western economy running to finance it all, some things may have been overlooked or postponed. This should come as no surprise to anyone.
PS: The bridge has been under repair since 2019 already, but only the part that is still standing has been completed so far. The collapsed part would have been next.
Typical winter climates in Germany have thaw-freeze cycles, so we use road salt. On bridges you need quite a lot as they are completely exposed to the atmosphere.
@@CaseyJones-Engineer Road salt on the part of a bridge that is used for trains. Keep digging.
@@hape3862 No, I'm sorry, but that's nonsense. Net investment in infrastructure in Germany has been around 0 since ~1998, so we have invested virtually nothing in the last 30 years and it shows. We have thousands of bridges that need to be replaced, our rail infrastructure is so old and obsolete that we will not be able to run an integrated timetable until 2070 - something Switzerland has had since 1982, and so on. Economy institutes in Germany estimate that we have an infrastructure defecit of 700 billion Euros, and it is getting worse because of the "debt break". This was a deliberate choice and it is now costing us dearly.
Have you hear about North Carolina's lake Lure dam is on the verge of collapsing?
Hi everyone, i have a question to the uplift detection method with the help of inSAR data. Are there ground-based measurements that allow the method to be validated? How is the traffic load on the bridge corrected during the recording of the inSAR data? I guess this factor has also an impact on the bridge movment....
It seems like these scanning companies should be offering a civil service package where a municipality could give them a list of critical infrastructure, and "if it moves, call us"
This is one reason why I'm hype for the future of comercial space, they are making it possible that this kind of tracking on an affordable scale. It's such a new concept that they have the data and don't even know what to do with most of it
Please cover the Lake Lure dam failure, Rutherford Cty. NC, predicted to occur soon , September 27, 2024, due to flooding from the recent hurricane Helene.
@@gustavderkits8433 Thank you. I will look into it!
It’s amazing the satellite can measure so accurately and we can draw any useful inferences from it, because pedestrians and trains over the bridge would naturally change the “height” of the bridge massively on different passes.Did they just measure a handrail or something?
When people question the wisdom of spending money on space-based technology, especially “mission to planet Earth”, it is things like this that can answer in concrete terms (pun intended).
Thank you for your reporting. Please keep up the great work.
Thank you! That is an excellent point. The return on space investment is huge.
How does the analysis of the satellite data account for the roadworks, that were ongoing on the bridge for the last years? They extended its width for pedestrians with new carbon concrete and renewed the road surface on both sides, during which time they removed the old road surface. The satellite data approach sounds promising though!
Surprising there isn’t a site that will interpret the data on maps. There is so much this could be used, such as glaciers, landslide, erosion, earthquake impacts..the list is endless.
Incredible technology. Given the number of deficient bridges throughout the US (and the world) this would provide some level of monitoring.
Very interesting. I wonder whether AI might be applied to the data analysis aspect of this.
Thank you. Yes, I think it could at some point. You are basically having to deal with massive amounts of data so a well-trained A.I. should be able to identify target areas of concern early on.
What does the InSAR data say about the closed bridge in Rhode Island and what about the various bridges constructed with T1, ASTM A514, Steel which have experienced Hydrogen embrittlement ? Can the effects caused by cracks from Hydrogen embrittlement be detected by InSAR observations ? If so, this may be an efficient means to evaluate structures prior to any need for closure or potentially allow early remediation.
You and I are on the same page. I will be getting data on such projects in the near future.
@@CaseyJones-EngineerThank you. Interested in the Rhode Island situation.
maybe engeneers around the wold may ask for analysis of specific objects in future to check. Oh could they check the building collapse in Miami/Florida if there are meassurepoints available too?
Anybody responsible for safety and maintenance of infrastructure like bridges should be able to access this information, at little or no significatn cost. It ought to be as routine as inspections, and much more frequent.
Every video is addictive and fascinating. I’m in Omaha and it’s scary to think about the two most used bridges across the Missouri River which we use to travel I-29 north and south as well as I-80 east. There are many bridges where we can see the steel frame and most show corrosion some awful. The farther north the more salt. As a younger man we traveled I-35W bridge which collapsed some years after we last traveled that to and from Duluth Mn
Thank you so much! I have been over all of those bridges too. Corrosion does a lot of damage.
In the UK, road bridges are typically designed to last 100 years. We have a lot of bridges in Europe, you don't want to be rebuilding them all every 50 years.
Could these type of failures be caused by fatigue failure? Maybe more so in concrete. Maybe related to distance from pilings and distance between pilings. Possibly related to a section in which there is a slight up and down bending. One side of the breakage is more anchored than the other side of the breakage. There is more leverage on one side than there is in the more anchored side.
That's a tremendous amount of data they're storing. Do you know how long they keep this information or how far back you can search?
A search can be made too around 2014 when the satellites were deployed.
thank you once again. your point of how western economies must pony up and fix or replace the necessary is spot on. it is not about spending it is all about investment.
The satellite monitoring could be a very powerful tool for transportation departments everywhere
Do you have any numbers on the other (still standing) bridge?
Just from camera view just before the collapse , it looks as though you can see a sag in that area. Didn't notice it the first video you made.
I don't see it, but it certainly is possible. The span broke into 3 parts, which then fell down.