Arizona Bridge Burns Down! - Massive Engineering Mistakes - Engineering Documentary

in Arizona a railroad Inferno takes down a vital River Crossing it was all engulfed in flam I was directly under the bridge as it was collapsing in California a trailblazing building Cooks up a storm in Downtown LA there would be blinding light reflecting off of the building into freeway traffic and that was a big problem in Ohio disaster unfolds as a driver and her vehicle are swallowed hole her car just C crashed and fell straight through it and in Sweden tragedy strikes a cuttingedge warship on its maiden voyage the most powerfully armed warship in the world had managed an operational career that was less than an hour long with big builds even the smallest mistake can be a huge disaster from miscalculations to misunderstandings some with deadly consequences these catastrophes are every engineer worst [Music] nightmare in big engineering strength must always take precedence over style because no matter how solid a structure looks everything has its [Music] limits like this railroad catastrophe in Arizona on a historic River Crossing hundreds of tons of rail cars crashed down onto the road below I actually heard the bridge as it was collapsing around me a disaster that made one of the hottest places in America even hotter it was one of the biggest fires I think I had ever seen it looked looks like the [Music] apocalypse Tempe Arizona just east of Phoenix basks In the Heat of the Valley of the Sun Bianca Bono is a local TV reporter here in the valley and here in Tempe we are definitely known for our extreme heat uh we are in the heart of the desert um and during the summer months we hit triple digits almost every single day it's the hottest area in the entire [Applause] country every desert Town needs an oasis and Tempe has this more than 3 km man-made lake which is the Beating Heart of the City 365 days a year any time of the day that you go to tempy toown Lake you are guaranteed to find people whether it's running cycling paddle boarding kayaking rowing crew it is so busy tempy was is actually founded as a crossing point over the river first by the and then by bridge over the decades dozens more bridges have been built here none more important than this one built in 1912 the Union Pacific Salt River Bridge is key to moving Goods in and out of the city across the Waterway this bridge is definitely iconic and it's it's as old as Arizona's statehood so Arizona is relatively new to the United States became a state in 1912 which is the same year that this particular Bridge was built at almost 400 m long with nine steel spans the Salt River Bridge was a through truss design like most rail bridges of its day today the Salt River Bridge still carries around 7 million tons of cargo a year including corn grain and lumber worth around4 billion doar do you see trains that are longer than a mile it's just so important to transport things from Texas to Arizona to California it's hugely significant early morning on July the 29th 2020 a 97c car freight train was heading from Tucson Arizona to Phoenix across the Salt River Bridge investigative reporter and local resident Camille kimbul was out for her morning ride and approaching the bridge when I start my day off by riding on the river it's just wonderful I was just at the tail end of my ride as Camille was going under the bridge the 11,000 ton train was directly overhead I could tell that there was a train above me cuz you could hear it ching ching ching shortly after 6 a.m. Camille's regular morning ride turned into a nightmare suddenly that Pleasant chinka chinka chinka sound disappeared and this loud crashing sort of noise I thought man this is loud and where I was at that point was right here right under this bridge exactly between the trestles the more than kilometer Long Train derailed suddenly and without warning bursting into flames taking part of the 108 8-year-old Bridge down with it within moment where I was standing between these two trestles directly above it was a lumber car it was a blaze and all the fire was falling [Applause] down and soon it was all engulfed in flame the grass the path I was directly under the bridge between the trestles as it was collapsing Camille got out just in time I'm getting kind of hyperventilated a little bit just going back to that experience because uh it was it was pretty terrifying news crews rushed to the devastating scene reporter Bianca Bono was stunned by what she witnessed it was one of the biggest fires I think I had ever seen it looked like the apocalypse and then to see that part of that bridge had actually collapsed it was quite shocking but the fire wasn't done yet three of the cars were carrying a highly flammable chemical solvent One releasing over 9,000 lers onto the ground below the Flames spread like fingers all across the bridge to the center of the bridge into the middle of the Lake Fire itself would just fall into the lake it was a tremendous sort of hellscape as fire Crews fought to bring the blaze under control the entire town was waking up to a major disaster this area was so flooded with First Responders and people that had just honestly rushed to the scene to get a look at it because they couldn't believe what they were seeing on TV the smoke and Flames not just from that side of the lake but the entire Valley could probably get a glimpse of what was happening here 12 cars had derailed and around 50 m of bridge collapsed in the Raging Inferno amazingly despite the destruction no one was killed or seriously injured I was incredibly lucky if I had circled around a tiny bit or something which I often do that flame would have got me I was literally moments away from being the one person who died in that accident being here that day it really was an unforgettable event and there are certainly visuals that I will never forget when the Flames died down people wanted to know what had caused this disaster but answers wouldn't be easy to find because the remaining evidence was a twisted burnt out pile of wreckage the investigation is ongoing but there's little doubt it was the fire that brought the bridge down the question is why did the train derail in the first place one theory is that tempe's extreme summer weather may have played a part we are seeing temperatures of around 115 1118 which is near record-breaking heat in this area um so of course there are experts that have said that heat can certainly play a role while the Aging track should have coped with desert temperatures regularly exceeding 38° C this intense Spike may have caused the rails to deform professor of engineering and construction Anthony Lano explains a possible reason uh is track buckling in high temperatures and we can model this with an example of a straw so as a track heats up it wants to expand but it can't because there's more track on either side if you have a lot of stresses in something that's long and narrow it tends to buckle that would clearly cause a derailment and as reporters like Bianca Bono discovered this wasn't the first derailment at this location just about a month prior to this incident there was another derailment in that almost identical spot there it was much more minor in comparison but it was in that exact location it was very surprising for us to learn that a derailment had happened and we didn't know about it the line was repaired and reopened just 2 days after the first incident they came back a few weeks later to do another examination and again they deemed it to be safe and reopened it so there were two inspections of that location that were done between the the first and the second derailment however it's possible these repairs played a part in the second more catastrophic event a research study found that rail buckling is more common after major maintenance work like the repairs to this line making derailment much more likely too but with the rails damaged by The Inferno it's a hard Theory to prove while the location of the crash might suggest a different story [Music] built structures like Bridges tend to have much more solid foundations than the ground around and as trains go from flexible to hard foundations and back again there can be an increased risk of derailment so the idea behind this uh theory is the track is behaving differently under the Train on the bridge than it does under the Train on the ground that is one of the leading factors to to derailments for trains when they approach and go onto the bridge and then when they come off of a bridge onto the ground the stiffness change can cause problems and that could be one of the causes of failure in this uh in this instance but if the track isn't to blame could it simply have come down to the age of the bridge one of the possibilities of failure with a steel trust Bridge is steel fatigue uh where repetitive loadings of a steel member can cause the steel to fail an example of this would be a paperclip we've all played with a paperclip we open the paperclip up still together close it back down maybe that's one train crossing maybe that's a th train crossings but if we do it too much back down eventually the steel fails only time will tell whether the heat the track the bridge or just bad luck was to blame but with two derailments in the same place only a few weeks apart chances are something was wrong while the blaze cut off a major rail route crucially almost 2/3 of the bridge remained intact and structurally sound Just 4 days after the collapse a 45 M damaged section had to be demolished then Crews got to work on the rebuild Engineers certainly pulled out all the stops and Incredibly they had this iconic Bridge rebuilt and reopened in just 15 days while the fire resistant capabilities of the bridge will undoubtedly be scrutinized whatever the outcome of the investigation hopefully both engineers and the industry will learn from the disaster master that struck this desert town as Engineers it's important to look at problems and find out why they happened so we can learn from those mistakes and figure out how not to let it happen again this bridge is as old as the State of Arizona it's been here for more than a hundred years if you come here today you would have no idea what this bridge in this area went through that [Music] day with Pioneer ing architecture Engineers are always pushing the boundaries but sometimes those boundaries push back like this oversight in California a design Masterpiece that was dazzling its downtown neighbors there would be blinding light reflecting off of the building into freeway traffic and that was a big problem a glaring mistake that had locals hot under the collar there were stories about traffic cones melting trash cans being lit on fire and an ingenious solution to take the shine of this standout structure sometimes when you push the limits there's a danger you can go a little too [Applause] far Los Angeles California what was once a small town founded by the Spanish in 1781 has grown to become a world famous Metropolis local journalist Kate dioma is a long-standing Angelino Los Angeles is an international City with multiple characteristics we have the Hollywood Glitz and glamour we have the laidback the valley lifestyle we have the beach Vibe Los Angeles is a one-of aind kind of place and one part of La has become a beacon for daring design downtown Architects recently in the last few decades have really taken on the challenge of living up to the the Hollywood glamour in the architectural sense really getting on board with showing off a lot of new structures going up that are really making a statement and arguably the one that kicked it all off was the Disney Concert [Music] Hall since opening its doors in 2003 the $260 million Concert Hall has been home to the LA philarmonic Orchestra and combines worldclass acoustics with eye-catching architecture it was a major deal when this was opened it was a grand gala the street was closed off it's a major celebration of this new architectural landmark in Los Angeles this stunning internationally acclaimed building has rightly become an LA icon it's covered by 6 and 1 12,000 steel panels no to the same in shape or size ensuring every panel would fit together seamlessly with its counterpart called for some serious creativity the solution was as bold as a design they took threedimensional software used in the production of French fighter jets to create buildable construction plans panel by panel senior technical designer kais alrai is an expert in computer AED design the Walt Disney Concert Hall is one of the first major projects to utilize computational software that have been taken from other Industries such as the Aerospace and Automotive Industries and apply it into architecture and engineering but this shining star of the Los Angeles Skyline would soon be making waves for all the wrong reasons shortly after opening in October 2003 trouble began [Music] so they finished this beautiful building and they discovered the surface was so reflective it was causing all kinds of problems as professor of architecture Mark Schiller explains the concert hall was once again making headlines there was an explosion of newspaper articles uh with catchy titles like Disney Hall is glaring back at you uh whose bright idea was this neighbors also complained that this bold building was shining too [Music] brightly everyone loved it except for the Neighbors because it was really super reflective and the sun Reflections were shining into the neighboring apartments and causing a heat wve the examples that were given by people who lived around the building were that the temperature in some of the surrounding Apartments would bump up 15° F within a period of 15 minutes it's reported that their air conditioning bills were through the roof and in the afternoon they had to keep their blinds down even though the sun was behind them just to combat the reflections from the concert hall it wasn't just heating up the neighbors nearby traffic was being dazzled too there's a freeway that runs right behind the building the 101 freeway there would be blinding light reflecting off of the building into freeway traffic and that was a big problem this shiny new building with thousands of Highly reflective steel panels was unintentionally harnessing the power of the Sun the County of Los Angeles they began receiving stories about things like spontaneous combustion of a trash bin or a melted traffic cone like a some people said death ray it didn't kill anybody please but it was dangerous and it did melt things and it was this r there were even rumors of bystanders roasting hot dogs on the street whether true or not they quickly became legendary it seemed that the trailblazing new concert hall Was Out Of Tune with the California Sunshine the big question was why Mark Shiller was brought in to investigate he discovered the problem was as clear as day the building has glare there's two kinds of glare there's the visual glare but there is also thermal glare or solar glare and that is where we are getting concentrations of sunlight and temperatures are going up very rapidly the glare was attributed to specific panels in the building's unique exterior senior technical designer kaai alrai explains glare from reflect activ ity occurs due to a combination of the geometry of the project as well as the material that is used uh the geometry itself directs the solar rays in a specific Direction and particularly when they are converging solar rays and then the material itself uh is what intensifies that reflection what we have is some surfaces that are highly reflective that are convex and they cause visual glare they make people squint they might interfere with traffic the other kind of surface that is so dangerous is the concave surface and this is because it concentrates all of the light that falls on that surface down into one spot as the sun goes by like that that spot goes by underneath like that think of those concave panels like a mirror if that mirror is placed in direct sunlight it can Focus the sun's Rays into one spot and potentially start a fire Mark and his team studied the impact of these hotpots in detail this little thing will measure the temperature and you set it and it records every 15 minutes or whatever you want to monitor the heat the tiny sensors were installed around the building in holes drilled in the pavement we found that the temperatures were getting into the 14 3 45° range some people say that that would be hot enough to cook an egg well actually you could cook an egg on that even though state-of-the-art technology was used to design the building it didn't predict this flaw I believe at the time of the design of the Disney Concert Hall about 25 years ago the digital simulation and Analysis tools were fairly limited and it was uh fairly challenging to perform a digital simulation that showcased is the reflectivity today we're able to do digital simulations both to check the geometrical Reflections and as well to check the intensity of those Reflections in comparison to the environment around people have asked us did you feel those those Rays yes absolutely while we were working on the building if you walk through one of those focal points you know it right away thankfully there was no serious damage but it was still something that needed to be fixed the question was how to solve the problem without impacting the concert Hall's unique aesthetic the first job was to identify the panels that were a potential danger to the public this is an example of the material that's on the building and it's these surfaces that can cause the problem so we found the surfaces were like that and we tested how we could treat them this was a film which did not change the look or color of the building too much but it it still was too much of a problem and so what we found was we had to find some other method while there's no doubt in the design was cutting edge the solution was definitely old school we took the panel and we began to test ways of uh solving the problem by uh modifying the texture so we used hand sanders we used an orbital sander and we used a linear uh vibrator sander we tested different densities of sandpaper in testing they found one solution that solved the issue but the only problem was now they had to apply it to around 400 square m of panels what we actually ended up doing was putting somebody in a bosen's chair on the side of the building with a hand sander and they sanded the portions of the surface that were causing the problem what they had to do basically was manually take the Shine off the building it just took enough of that off so that the nature of the building was not changed uh and that was our intention solve the problem without destroying the art of the building now more than 15 years later while the Concert Hall may have lost a little of its gloss it still continues to shine as a beacon of groundbreaking design and development in Downtown LA when the Disney Concert Hall was built it really was the birth of the Renaissance of downtown Los Angeles I think architecture that can be enjoyed is a wonderful phenomenon so I think what the designers learned from this is that it's great to do a flashy building as long as it's not too flashy when engineering goes wrong catastrophe can strike in plain sight but some fails lie hidden just beneath the surface incredible and that is oil like this disaster in Ohio which shocked a whole city her car just crashed and fell straight through it an engineering fail that took out a highway there was pieces of kind shearing off and falling all over the place and a Race Against Time to save a driver trapped not on but underneath the [Music] Road Toledo Ohio sits at the Western tip of Lake Erie founded nearly two centuries ago this modern Metropolis grew from Humble foundations Tom Henry is a local journalist one of Toledo's nicknames is frog City it's based on our connection to the great Black Swamp which was a major historic swamp in this part of the [Music] country frog city is famous for its automotive industry and glass manufacturing yet it was the fertile farming ground that paved the way for success but wet ground and growing cities don't always mix July the 3rd 2013 12:15 p.m. a school principal was driving home on Toledo's North Detroit [Music] Avenue she was just like anybody else driving along and you can see how busy it is now she saw somebody in front of her go over something just looked a little a little different as the principal drove over the same spot the road beneath her suddenly gave way her car just crashed and fell straight through it she was Free Falling Down many feet as many as 20 ft a giant sinkhole had opened up swallowing the vehicle the driver was trapped and water from a burst Mane was pouring on top of her car is there water filling up in the hole yeah doing up the hole she's uh moving a little bit if you guys can heard she's raising her hand they're coming lights and S firefighter Lieutenant Pat Lanahan got the call I was pretty shocked to hear sinkhole especially in a residential area like that and a car involved as well was quite shocking we got the Run we jumped in the rig and we headed out the doors as water continued to gush out Pat and the team swung into a action you clearly see the driver was in distress at the bottom of the hole with a large volume of water she was obviously very distraught of the situation with a terrified driver and water now coming into the back of the car time was of the essence she was afraid of getting out of her vehicle until she knew it was safe she had said sweet Jesus Jesus Jesus she kept hoping that Faith would get her through it in danger of sinking further and with the situation deteriorating the rescue team needed to get her out fast there was pieces of concrete shearing off and falling all over the place thanks to the quick actions of Toledo fire and rescue the driver made it out unscathed once we got her out that was a huge thing for us uh and a big relief once we had got out and no one got hurt she was lucky to survive the impact in the first place that must have been a very horrifying event with a gaping hole in North Detroit Avenue the people of Toledo demanded to know what had happened the broken water M seemed like an obvious clue but investigators quickly ruled that out as collateral damage from the collapse the problem lay much deeper with two old sewer pipes that had ruptured like a lot of old cities a lot of our infrastructure is aging uh and some of it's well over 100 years with roads water lines sewers you know it's difficult to keep up with a lot of this when something is out of sight it can also be out of mind especially when it comes to sewage being old cast iron pipes it can create a slime layer that produces toxic gas that gas was hydrogen sulfide water engineering expert suou seanan explains when the hydrogen sulfide from the switch uh have a chemical reaction with the oxygen in the sewer system it form a chemical component known as sulfuric acid which is a very highly corrosive chemical and can reduce the thickness of the pipe sulfuric acid had been corroding the inside of these pipes for about a Century Two key sewer lines had been getting weaker and weaker and it was all hidden from view but corrosion alone hadn't triggered the collapse when these pipes were installed there wasn't much traffic around and vehicles were much lighter these days roads everywhere get heavy usage from trucks and just a sheer volume of traffic that heavy pounding makes its way deep underground and can damage the pipes even further nearly 100 years of corrosion combined with increasing traffic explained the failed pipes yet there was an additional mystery when the pipes were originally installed they were firmly supported by compacted Earth but when the sinkhole opened up it revealed a vast hole where the dirt should have been as more and more cracks formed the sewage flowed out through these weak spots washing away the ground beneath the Road in a process known as exfiltration exfiltration of switch occurs around the pipe and it washes out the soil particle around the pipe and this lose lots of soil particles around the SE system in a long term uh can result in formation of large single over time both the liquid and material were washed away leaving the massive void under the road just waiting to collapse so Engineers quickly went to work repairing the pipes and rebuilding the road there was a challenge because of how wide and how deep it was from an engineering standpoint but they did a pretty remarkable job in fixing it took about 5 or 6 days this was a very narrow escape the collapse was so quick and so huge it's amazing other vehicles didn't end up in the hole across the us there have been multiple sink H holds like this so the next question was how to prevent them I think one of the take-home messages is that you really need to investigate your infrastructure you need to stay on top of it you know what's beneath your feet what you don't see just because it's out of sight shouldn't be out of mind in 2002 the city pledged more than half a billion dollars to in inspect up to 160 km of pipeline every year in a project called the Toledo waterways initiative it was a horrible incident it ended up in a positive manner in that we were able to get the patient out of there with no serious injuries but we hope that this never happens [Music] again in big construction Engineers are constantly innovating with bigger Bolder and grander Designs but if things go wrong the catastrophe can be just as massive like this disaster in Sweden an ancient warship with a fundamental flaw ship design was basically trial and error and here there was a major error the pride of the Navy sunk less than 1600 M into its maiden voyage the most powerfully armed warship in the world had managed an operational career that was less than an hour long and a tragedy that turned to Triumph with a resurrection more than 300 years later this was no quick fix even today Engineers are in a constant battle to save this historic wreck Stockholm Sweden's capital founded nearly 800 years ago it's made up of 14 Islands connected by over 50 Bridges surrounded by water on all sides it's also known as the Venice of the [Music] north historian Dr Fred Hawker has lived and worked in the city for over 15 years Stockholm was established to be the main city largely because it's very sheltered from the wind from almost all directions and it's sheltered in a strategic sense it's very difficult ult for an enemy to get all the way up here to threaten the city by the 17th century Sweden was at the peak of its power controlling areas of Denmark Finland Germany and even Russia Sweden was an aggressive imperialistic power uh we were the the bullies of the Baltic the King was trying to build up the Navy and for that he needed not only more ships but new kinds of ships in 1625 as a symbol of Sweden's growing Maritime might the king commissioned this the Vasa this was the first double-decker warship in Sweden's history and still holds a special place for the [Music] nation today around a million people a year visit its Museum where Fred Hawker is director of research B was cutting edge the basic configur duration of vosa two full decks of heavy guns would end up being the fundamental backbone of most of the big navies of Northern Europe at around 68 M long and over 48 M tall the sturdy Oak ship was fitted with more than 64 cannons but as one of the ship's modern-day Carpenters Robert Jonson explains the Vasa was about more than just Firepower it was um not only a worship but also a a symbol of big Sweden as the dream of big Sweden so we were a major project the finest Builders but a fundamental flaw meant this trailblazing weapon of war was Journey Bound for major disaster Sunday August the 10th 1628 the Vasa set sail for the citizens of Stockholm this big ship was a big deal when the ship took off on its maiden voyage everybody in Stockholm was watching the banks on both sides here were fill of people because this was the most powerfully armed warship in the world crew members families were on board for the big day and would swap place with 300 soldiers before the ship headed out of her base on the edge of the Baltic condition were calm as they headed out of port after they set sail they were coming down along these Bluffs and this little dip in the Bluffs channels all the wind from the southern part of Stockholm into a big gust that blows straight across here around 1500 M out a gust of wind caught the mighty ship as the ship got really right out in front of the middle of this Gap the main strength of the wind took the sails and it healed the ship over water began rushing in through the open gunports as ship's Carpenter Robert Jonson explains the Vasa was now in serious trouble imagine looking out and seeing water pouring in Feel the fear of seeing what is happening with all this water and Chaos the Vasa was sinking people were scrambling to get out of the below deck part of the ship and get off the ship and then right about here where we are now the ship went under the water what began as a celebration had ended in tragedy we have quite a few skeletons found on board the ship a lot of people couldn't get out of the ship while the exact passenger numbers aren't known and many did manage to escape sadly 30 people died most trapped deep inside the ship they're all clustered near the feet of ladders once the ship started to tilt over it's very difficult to climb a ladder that's leaning to one side but why had the pride of the Swedish Navy vanished in front of people's eyes just over a kilometer from Shore unbeknown to the public it seems a major concern had been raised before it ever set sail crucially the captain told the vice admiral that the ship was unstable he even gave a demonstration just 30 men running back and forth on the upper deck was enough enough to make it roll as ship's Carpenter Robert Janson explains this instability was all down to its revolutionary double decker design the V is well constructed but the dimensions are a bit wrong the problem with the ship Builder he had never built a ship with two gun decks while Advanced for its time it turned out that being ahead of the game was part of the problem in this 1600s the use of accurate mathematical models to predict a ship's stability was still more than a 100 years into the future the mightiest warship Sweden had ever designed was built using a system of trial and error there were no drawings just people saying this is the width and this are the dimension and then with up to the Craftman to put it together no drawings just knowledge what to do and when to do it in their Ambitions to build big the Vasa had been designed Too Tall and narrow causing her to be topheavy every ship has to balance certain forces it has to balance gravity pushing the ship down and buoyancy pushing it up in such a way that the ship wants to stand upright and in vos's case gravity is acting much higher on the ship than the buoyancy keeping it a float is and so when it heals over gravity wants to keep pushing it over or as one of the people at the inquest said the ship doesn't have enough belly vassa's centeral gravity was simply too high and once Water started pouring into the gunports there was only one way the ship was going down the Vasa sinking wasn't the end of the story more than three centuries later Salvage experts attempted to raise it From the Bottom of the Sea in a Titanic feat of engineering Navy divers dug tunnels under the ship and used steel cables to suspend the hall like in a basket before slowly lifting it free of the mud little by little over more than a year on Monday April the 24th 1961 with thousands of Spectators once again lining the shore more than 300 years after she sank the Vasa finally rose again from the darkness what's even more incredible is that they managed to seal the hull enough to make the three Century old wreck float again the king of Sweden even went aboard to celebrate vassa's Resurrection divers spent 5 years recovering thousands of scattered pieces while scientists got to work preserving the ship Museum conservator Johanna s anstrom explains the gun ports had fallen off the top deck was almost gone and all of the sculptures had fallen off so she was meticulously pieced back together into uh what we see today and she's been called one of the world's largest jigsaw puzles saving Vasa would be no easy task every piece had to be preserved no matter how long it took she was sprayed for 20 odd years with a substance called polyethylene glycol which is a water soluble wax so she was sprayed continuously and after that she was air dried slowly for 10 years before she took her place in the new Museum built for her on June the 15th 1990 after nearly 30 years of painstaking preservation the Vasa was finally ready for the public to see her again in in all her former glory amazing 97% remain of vosa and people who come in this Museum one word that occurs is wow history everywhere you look a sunken ship is taken up and is so well preserved that is U oh surreal but it's real and with a dedicated crew constantly working to keep the Vasa in Ship Shape this Maritime Marvel should be around for years to [Music] come

Channel: Banijay Science

Views: 48,939

Keywords: Arizona Railroad Disaster, California Reflective Building, Ohio Sinkhole Incident, buildings, construction fails, documentary, engineering, engineering challenges, engineering disasters, engineering documentary, engineering errors, engineering fails, engineering lessons learned, engineering mistakes, failed constructions, fails, massive engineering failures, mechanical engineering, saving buildings

Id: 1tKVaU6Tul0

Length: 44min 47sec (2687 seconds)

Published: Tue May 28 2024