Verrazzano-Narrows Bridge - Wikipedia
Does the Golden Gate Bridge have the world's longest suspension span? What is the elevation What about one-way toll collection, when was it instituted? When did We do not have the exact employment figures. During construction, the net saved the lives of 19 men who became known as the "Halfway-to-Hell Club." . It's reached by cable car rather than road or hiking path, limiting There are three basic reasons that bridges stop mid span or don't The Half-Bridge of Hope in Russia is a wooden structure that looks like a .. Send it to me!. Meet Me Half Way Lyrics: In a lifetime / Made of memories / I believe / In destiny / Every moment returns again in time / When I've got the future on my mind.
The Langkawi Sky Bridge was designed to give people a view of the Malaysian jungle. The footbridge was helicoptered to the top of Machinchang mountain. Unfortunately, the bridge has experienced structural issues that have forced officials to limit access.
However, some bridge structures go no place at all. Check out these amazing examples: It is part of a highway system that was never completed. There are currently no plans to finish the structure. An interesting two-lane bridge in Pavlovsky Posad, Russia was built in Traffic crosses it over the Vokhna River in one direction only. Officials hope to build a road once railroad tunnel construction in the area is completed in the next few years. The Half-Bridge of Hope in Russia is a wooden structure that looks like a bridge reaching from one hill to another.
However, it serves no logical purpose. It simply exists as an art installation and engineering marvel. Check out these bridges that not only move traffic across major waterways but also play a vital role in border security: The Peace Bridge is located on the east end of Lake Erie. The Bridge consists of five arched spans over the Niagara River and a Parker through-truss section over the Black Rock Canal on the American side of the river.
The bridge is just over a mile long. The Peace Bridge was completed in and named to commemorate a century of peace between the United States and Canada. Unlike other border crossings, this bridge is owned and operated by paper mills on the U. This arrangement helps facilitate commerce.
The Thousand Islands Bridge was constructed in and added on to in This series of bridges span the U. Canadian border over the St. Lawrence River in the Thousand Islands region. While this is a complex bridge infrastructure system, the actual international border crossing is a set of two parallel foot-long bridges between Wellesley Island in the United States and Hill Island in Canada. Traditional bridge designs can be as stable than modern ones Pons Fabricius, Arkadiko, and Anji Bridges are shown left to right.
With arch bridges, the entire structure is under compression, which is dissipated out and down from the center through the arch, right into the supports. Historically, some of the longest-lasting limited-distance bridges are built around arches. Here are a few examples of arch bridges that have withstood the test of time: It is the oldest bridge in the city.
Overall, the structure is feet long and 18 feet wide. It includes two broad arches, supported by a central pillar. The ancient Romans constructed some of the most durable bridges ever. According to Guinness World Recordsit dates from B. It dates back to the Greek Bronze Age and is one of the oldest arch bridges still in use.
The structure is 72 feet long, 18 feet wide, and 13 feet high. The bridge was originally designed for chariot use. At the time it was built, it had the longest arch and was the most technically advanced bridge anywhere in the world. The fact that it has made it through floods, earthquakes, and other natural disasters is a testament to the quality of its construction.
The highest bridge on earth was completed in Back in September, the Beipanjiang Bridge, in mountainous southwestern China, was opened to traffic. It rises 1, feet above a river. For these construction workers, the job will be as tough as any they've seen.
They'll work in all kinds of weather, and even put their lives on the line. Their average experience is fifteen years. And as for their attitude, it's simply get the job done and get it done right, and then move on to the next job. For the general contractors hired by the Illinois Department of Transportation, the pressure will be even more intense.
In construction, above all other businesses, time is money. Some of the contractors have even staked their company's future on finishing the job on time. Like Bill Webb, they've all made fixed bids, which means they'll all have to pay for mistakes and delays out of their own pockets.
I've made this statement several times before, it's about one step away from going to Las Vegas and rolling dice. It's a little bit, a little bit less risky than that, maybe. Supervising the contractors is Earl Doerr, the project manager, or resident engineer for the Illinois Department of Transportation. A farmer turned engineer, Doerr still lives near the family farm forty miles down river from Alton. Doerr is as good-natured as they come, but he's also determined to keep the contractors in line.
I don't know if you could say we're distrustful or trustful of contractors, but we do have to watch all the operations to make sure that they're done properly. And that's not to say they were done wrong intentionally, we just want to assure ourselves that all the pieces fall into place in a proper fashion and that all the material is good material.
There's a separate contractor for each section of the bridge: As construction finally begins, Joe Leach oversees the placement of a huge steel frame which will rest on the river bottom.
The anchoring of the frame is the first step in the construction of the main span foundations. We don't necessarily build this thing in a progression from one bank to the other. For example, in this project, we're starting in the middle of the river. In starting there, you have to make sure that everything is in alignment so that everything later will attach to it properly, so that it will fit. The closer you are to, shall we say perfection, the better the end product. Making sure each frame is aligned perfectly requires precise measurement and constant maneuvering.
Let's get this thing in alignment first, OK? From this fixed point of reference, the surveyor will shoot a laser beam at this mirror mounted on the foundation frame. The frame is in position over the place where one of the foundation piers will be.
By measuring the time it takes for the reflected light to return to the shore and the angle at which it travels, the surveyor can calculate the frame's precise position. But the powerful current makes it hard to keep the barge from drifting out of position. My boat's got me now, I'm going upstream. I'm holding myself down. How are we on alignment now? Hold what you got, hold yours Robin. A little more Robin. Knock off a little bit T.
When the frame is in the right place, foot long steel shafts called piles are lowered through the corners. Let's move him up. When the pile hits the bottom, it will sink into the mid a few feet. Then it will be pushed another 60 feet down.
When all four piles are driven in, the frame will slide into the water. Once the frame is in place, it's enclosed with a tongue-and-groove steel wall, slowly, step-by-step, one narrow panel at a time. The finished box is called a "cofferdam. Then eight feet of concrete is poured in to seal the bottom. With the cofferdam holding back the river, it can now be pumped free of water enabling the crew to work beneath the surface. The crew's first task is the construction of an elaborate grid of reinforcing steel.
The grid will serve as the skeleton for the finished concrete foundation. Most of the reinforcement for this project was a massive jigsaw puzzle. The importance of this reinforcement all gets back to the fact that we do not allow concrete to take any tension. Now it'll take a minute amount of tension, but concrete, to look at concrete, it's like a piece of chalk, it's very brittle. And it's very easy to snap. And where it starts to break or snap is where we have to have this reinforcement in there to take that tension.
Each reinforcing bar, each level of the grid has been carefully designed by the engineers for maximum strength. When the reinforcing steel is buried in concrete, the finished foundation, called a "footing," will have to carry the weight of hundreds of thousands of tons.
It's shortly after dawn on a chilly December morning when the first concrete pour begins. For the next 15 hours, trucks will arrive every seven minutes, loads of concrete in all. The concrete arrives already prepared. A sample from each load is tested just before it's poured to make sure it has the right consistency, too much water will weaken it, too little will create air pockets when it hardens, reducing its strength.
After testing, all the concrete needed for this footing, about two thousand tons of it, is pumped through a long pipe to the crew in the cofferdam below.
The pour cannot be stopped once it begins. It has to be continuous, to ensure that the concrete sets properly. Twelve feet below these men, the reinforcing is so tightly placed that the concrete won't flow without help from electric vibrators. But isn't easy to keep your balance on the slippery steel. Sometimes, it's like down in that hole. If a guy would make a wrong move down there and you'd be singing soprano the rest of your life.
So you never know what's going to happen on a construction job, you know? Things be going along good and all at once everything starts going bad.
But today, the work has gone smoothly, but there's nothing more serious than the usual aches and pains. The pour is essentially complete. We probably got another half hour to go yet. The men have done their jobs well today, and you have to consider they've been here since 7 o'clock this morning and it's now getting close to 10 o'clock. The same crew's been at it all day. And you can imagine their arms and legs are pretty tired.
Oh, that's a job, buddy. That was a day's work. All of these hidden things, and that which was built below water are very important. The foundation for this bridge, itself, is one of the most important things we could have because that is what holds this whole thing up.
If we had pilings that weren't driven properly or weren't driven to the right bearing or to rock, we could have a possibility of the whole thing sagging to one side or the other. So these things that can't be seen is what the public puts a good deal of trust in engineers to make sure that this stuff is properly installed.
The next step is the construction of the foundations for the Missouri approach to the bridge. Here the engineers have had to be unusually innovative because the river is 70 feet deep on the Missouri side and the pressure at the bottom would crush a conventional cofferdam.
Their solution is to build a platform on stilts 40 feet up from the bottom where the water pressure is much less. This platform will then serve as the base of the cofferdam. Next, 24 steel tubes are hammered all the way to bedrock and filled with reinforcing and concrete to become the permanent supports of the Missouri approach foundations. Then the walls of the cofferdam are built panel by panel. The holes in the concrete slab where the tubes go through must now be plugged by hand.
The work is handled by a few men taking risks that most would shun. They begin one frigid morning. It's pretty cold down there. You can make it about an hour before you get real cold, and we'll be taking turns, me and him, we'll be taking turns doing it. He'll probably be in there 45 minutes or so. There's no visibility at all. You just feel around down there. I have my hands on the pipe. Drop a little one in there. Here comes a little one. There's a concrete pad down there that is supported by these rebar and these 30 inch pilings are drove through there and he's sandbagging around the piling so when they pour the seal down there, that the concrete doesn't run out around the pipes.
Throw me about four. Four big ones, Tom. The bags contain sand and cement that once submerged will harden into concrete, sealing the holes. Only then can the coffer dam be pumped free of water.
But the diver's work isn't over yet. Two sections of reinforcing steel must still be lowered into each of the tubes before they're filled with concrete. But while the crew is working several sections break loose in some of the tubes. When the crew fails to fish them up with a hook, they have to send down a diver. The 30 inch pipe, and it's a, well real close quarters. You got claustrophobia, you'd never get down there. The diver's lifeline is an air hose connected to a compressor. After he descends, he'll feel for the top section of the steel with his feet.
When he reaches it, sixty feet down, he'll tie on a lifting line and signal to be hauled up. Ten minutes later, the signal comes. It's an exhausting and dangerous dive, but it's only the beginning. Three more sections of reinforcing steel will be snared by the diver in this cofferdam alone before the day is done. While construction continues, the river flows inexorably towards winter.
If anything, the pace has quickened. Barges and tugs by the dozens pass Alton each day filled with every conceivable type of commodity. Leviathans of steel, dwarfing other vessels, they are piloted by the inheritors of Mark Twain's legacy. Steve Wedding has been a river pilot for 25 years.
I've got soy beans, corn and wheat. About 21 thousand tons overall here, total tonnage. Twelve of the loads came out of St. Finished me out to 15, which is as much as we need to bring out here south, and that's all the locks will hold, for that matter, is fifteen loaded barges southbound.
A lot of these bridges up here on these rivers were built for old time packet boats, paddle wheelers. They weren't the size of this boat alone, much less a thousand feet of barges in front of you. I'm a hundred and five feet wide and when you're trying to stick a thousand feet of this through there with a cross current running through it, it can be very ticklish. My grandfather and his brothers pushed old wooden barges and carried cider out of Calhoun County, down here to a vinegar plant in Alton, and they had a small boat and dredge and they dredged to begin with, was dredging sand on the Missouri River and started a fleet over here, and it just grew from there.
The Mississippi has always been a working river, attracting men like Steve Wedding and his ancestors. Twenty-three hundred miles long, it's the nation's greatest waterway. But at more than a mile wide in many places, it is also a great divide splitting the country in two. Until the mid's, there wasn't a single bridge that spanned it. A pioneer family heading west might wait days for a raft to take them across. For years, even the people who lived in the river towns had to rely on ferries.
Inevitably, the fast growing but bridgeless cities on the west side of the river felt cut off from the eastern side and its commerce. Crossing the river became even more important with the coming of the railroad, tying the country together in a fast growing network of transportation. Finally, ina new era began when the first bridge across the Mississippi was built between Rock Island, Illinois and Davenport, Iowa.
But there was trouble almost immediately when a steamer rammed the bridge and sued the railroad. Arguing for the defense was a young lawyer named Abe Lincoln.
Lincoln won the case and bridges have spanned the Mississippi ever since. Although most of the earliest ones have long since disappeared, a few remain, triumphs of design and engineering. These are the ancestors of the new Clark Bridge at Alton. When the main span foundations are finished, it's time to build the towers on top of them, section by section until they rise three hundred feet above the water. McCarthy Brothers Construction of St. Louis has less than a year to finish the towers.
Ted Downey is the project manager. Working over water is one of the toughest things you can do. You have to plan every morning, which we do, we meet every morning with the staff for just a few minutes because you can't just walk out and take something or drive out and get somebody.
Everything has to be maneuvered by tugboats and barges. At 7 in the morning, the McCarthy crew of about 30 is taken by boat to the site. Already, the dike has been extended to the Illinois main span foundation by the Army Corps of Engineers.
Today's job is to add more reinforcing steel to the foundation as the tower grows. This wire will hold the horizontal reinforcing bars in place until concrete is poured. But the vertical reinforcing will get special treatment because it must carry more weight. It needs a connection as strong as the steel, itself.
So on the end of each vertical bar, there's a steel cylinder, or sleeve, guided over the end of a ridged bar already embedded in the foundation. Then a splice is made by a special tool called a swager. It squeezes the sleeve so tightly, that both ends of the bar are joined together in a permanent bond. After 3 months, the first sections of reinforcing steel are covered by concrete.
The towers are now 70 feet above the water. But in the late Fall here, the weather often takes a turn for the worse. A rising wind is the harbinger of winter. Just as the steel forms for the next concrete pour are hoisted by crane, the wind decides to gust.
Lately our luck's been running pretty sour to be honest with you. We, and behind us here, that form above on ten, we had problems with that. We attempted to set that form three times, and had to set it back down. You've got to control it. The wind controls it. In other words, you don't control it.
Yeah, if the form would happen to spin, like I said before, and got hung up in this boom, that could be bad. He could loose the boom. Or it could knock somebody off, you know, off the column. Or it could damage the existing concrete, the re-steel or even a form if it got, you know, got away from us.
But those are one, those are some of the hazards of setting, you know, these big forms like this in these high winds. And we're talking about 30 to 35 mile per hour gusts. Yep, and what you see is what we're going to get for the rest of the day.
The 39 Most Amazing Bridges In The World | HiConsumption
It's not going to let up any. You don't think we could just get up there and tie it to it and ease it up and slip it down over the re-steel? It'll catch a lot of wind. I'd rather not do it. Better not do it. That afternoon rain arrives on the heels of the wind.
But on the ground, work continues on a new section of reinforcing steel. When it's finished, it will be lifted to the top of the tower in one piece. The iron workers have special guides or jigs on the deck to make sure they assemble the bars in the right pattern. The reason for all this intricate lay-out work is that this tower tapers ever so slightly from elevations say all the way up to So each band that we make has to be individually laid out, which is very unusual for reinforcing steel work.
There are nearly four miles of steel in this section. It weighs forty-five tons. The section is so heavy, a warning siren goes off on the tower crane, which can't bear the weight alone. Once in the air, it can only be handled by another more powerful crane on a barge. The crew must now match up each splice with its mate.
It will take a day and a half to finish the job. From now on the towers will grow in these forty foot increments. And the efficiency and safety of it all depends heavily on one of the most isolated men on the job, the tower crane operator. He can make the difference between profit and loss. I detest heights, but up there I'm inside of a cab and it doesn't bother me when I'm high.
But, it, no, it really doesn't bother me. Just take a beam this size and put that thing ten feet off the ground and I couldn't walk it. But something like that, if I'm inside of something, it's like a safety factor for me. That's the way I am, it's the way I've been all my life and I always will be.
Just getting up there, it gets you awful winded. It's a long climb. That's my home for nine or ten hours a day up there. On a clear day I can probably see twenty miles. When I get here, they go to work. Once the steel forms are in place, the next concrete pour can begin. At first, everything seems to be normal. There's only one problem: I took a hammer and chipped some of the concrete off the surface and I noticed that it was very soft, it was very lightweight.
I took a sample down with me to the field office and I noticed it was so light weight, it would actually float on the water. When you're stuck with over hundred cubic feet of bad concrete, your options are extremely limited. In fact, you have only one: We're in the process now of taking it down to a certain elevation that the state says where's good concrete.
Probably as you know it throws us way off. Completely shuts, you know, basically the whole job down, as far as pouring. No one likes to hang around because of a supplier's mistake, especially when you're losing money. With the bad concrete, there's a greater temptation to make up for lost time by speeding up the work and taking more risks. There's a danger, yes. If you get too involved with the bridge, I mean if it becomes your sole thought in life, you begin to forget about the human beings that are actually building it, and that's something that in the building of these things you can never do.
It's pretty dangerous work for these guys, it's very dangerous work, as a matter of fact. But we're extra careful out there, we put a life belt on anything that moves, you know, that's just the way it is. It's the nature of the beast. Every construction worker knows someone in the trade who was in the wrong place at the wrong time. We had a friend of ours who was just killed a couple weeks ago, you know? Accidents, some unforeseen thing. He hooked onto a load and evidently he was under it or in the path of it and in some kind of a way it worked out of the chokers and fell on him, you know?
Broke, you know, a number of bones in his body and a couple of weeks after he died. So, most of the guys out here are really safety conscious, the company is safety conscious, itself. We don't want to see nobody get hurt.
To be safety conscious is not always enough, though, as each worker knows. Consider the case of Tim Summers, a carpenter, who owes his life to a stroke of luck.
Some would call it a miracle. If you got a picture of those tower cranes that's over there, he basically fell maybe a foot, it was quite a fall, just lucky he didn't, you know, he didn't get killed. That's the, you know. I don't know how to swim, so this life vest is the only thing that did it for me.
The she bolt gave on the scaffolding and I fell about 75, 80 feet. I hit my head on something on the way down, I'm not quite sure what it was. I hit the water, I missed the barge by 12, 15 feet I guess.
That was where I lucked out and I just popped up.
The 39 Most Amazing Bridges In The World
Just came right out of the water and grabbed onto the ladder, it was right there, and climbed right out. Like nothing ever happened. It was like something happened, I just happened to luck out and not hit the barge and the ladder was there, otherwise I'd have been right underneath the barge.
The kind of stoic understatement rules here, but it doesn't take outsiders long to figure out just how dangerous this job really is. All you have to do is look around. Just watch as two iron workers finish off the latest section of reinforcing steel, feet above the water. So far, no one has been seriously injured on the job. Then again, there are still 20 months to go.
It's now February 10th. A typical 8 hour shifts beings at 7 a. Most of the workers live within 15 miles of the site, but some had to travel more than an hour to get here. Today, it's cold and raw, but the camaraderie of the crew is, if anything, stronger.
Let's go to work. If you're a construction worker, you have to show up no matter how miserable the weather, because you won't get paid unless you do. The workers pride themselves on their toughness. But winter on the river is especially hard. The sky promises more snow. An hour later, it begins to fall lightly, then more heavily. It's good weather to get frostbite and stuff. There's just no need to take a chance. It's a little unbearable up there this morning.
It, that wind's blowing about 25 to 30 miles an hour, and it's about zero. When you got to depend upon climbing around and your finger's are getting cold and stuff, it's just too dangerous for me up there. I don't feel comfortable. A few of the carpenters, we had that, the weather sock blew off the top. We got it pulled down, but I think they're all gonna come down, too, before long, when they get a little taste of it up there.
They just come up after we did. Can't keep a hard hat on. Your hard hat blew off. Like I said, I just think it's too dangerous up there this morning. There will be more snow throughout the winter. It's a constant struggle to keep from falling behind. Despite the weather, the two towers are nearly finished by the spring. Within a few days, one crew puts in the first steel girders that will support the road deck.
At the same time, another crew is getting ready for the final stage in the tower's construction. This curved, saddle-like structure will crown each tower and hold the bridge's cables. It goes up in two pieces which must be joined at the top. Later, this space beneath will be filled with concrete, permanently supporting the plates and the cables that will drape over them.
And so for the last time, buckets of concrete are sent to the top of the towers. When the concrete has set, the steel forms are removed. The towers are finished at last, the end of a long struggle against time. The towers aren't the only part of the project, however. On the Illinois shore, another contractor must build the approach leading to the bridge and he's already running late.
Things quickly go from bad to worse. An accident stops construction in its tracks only a few weeks after it begins.
A crane is tipped over while trying to lift an oversized load. Worse, the operator may be hurt, although how badly isn't known yet. He'll be taken to the nearest hospital for tests. This is the moment that everyone dreads, the possibility of a serious injury. Fortunately, the man will recover, but the same can't be said for the schedule. There are further delays when dredging begins for the underwater foundations.
Something is down there that the crew didn't expect. We couldn't complete the excavation cause we hit something and couldn't get through it, around it or under it, so we sent a diver down to take a look at what we had and that's when we found out we had a barge. And they're chopping through the inner bottom right now and it could be up to two hundred feet long, and all's we need is a section big enough out to get our pier in right here. We can't do any work here on Pier Number 13 until this is resolved.
And one of our cofferdams is directly over this sunken barge. So until that barge is removed, we can't go to work on Pier Number Number 13, that's a lucky number isn't it? That's part of the risk of doing business. With this huge square of rusty steel removed, the crew can finally go ahead with Pier Number But the river yields to the bridge only with the greatest reluctance. Even though at the present time things look relatively calm with the river, we know that it can give us problems, that it's, and it tends to be rather unforgiving.
Some writers have even referred to it as a great brown God, and I think that's one of the things that some of us, anyway, those of us who have worked on a river before, certainly have a healthy respect, and will always attempt to maintain a healthy respect.
But respect may not be enough in the months to come when even the bridge, itself, will be threatened by the river's might. It's now two years after construction began, and the most challenging and nerve-wracking phase lies ahead. For the next 16 months the crew will have to wrestle with untested techniques, costly mistakes and even the river, itself.
By the summer, the main span towers are finished and the crew is getting ready to install the first cable stays which will support the road deck.
Each cable stay will run from one side of the deck over the top of a tower and then down to the other side. A stay consists of from 19 to 46 steel cables housed in a protective steel tube called a banana pipe, named for its color, and a flexible black plastic pipe for weather proofing.
At the ends are anchorage devices to help fasten the stay to the deck. The cable for the stays is made in Jacksonville, Florida. They're about miles of it wound in spools. Specialized machines spin the cable out of seven strands of high strength steel. To resist corrosion, the cable is then coated with epoxy. It's also covered with white grit. The grit will keep the cables from slipping once they're bound together.
The last stage is the water proofing test - crucial, because even minute spots of corrosion on the steel can lead to a devastating failure. Another potential problem is the enormous length of the cables, because they're designed to drape over the top of the tower in a continuous strand.
As it turns out, the extra long stays quickly make for a construction nightmare. Initially, we were pulling the cables through the banana pipe up there, one and two at a time. By the time we got 37 cables pulled through, why a good deal of the cables were unusable in the pack. This was the method he had chose to use and we thought it's up to him to give it a try. And after he had done that, we took it apart and looked at it and this is what we found. One cable is actually rubbing over the top of another cable.
As you can see here, it took off some of the epoxy coating, which we don't want. This coating that's on the cable stays is very abrasive and as one cable was pulled across the other, it actually cut into the cross-sectional area of the steel, itself, which would detract from the strength of the cable. A month and a half has been wasted, along with thousands of feet of cable. There's no other choice but to start over from scratch.
Now we have developed a system of pulling the cables out individually and then putting them all together and pulling all of them together through the banana pipe. So they only make one trip through the banana pipe and they don't wear on each other and it looks like this is going to be the way we're going to travel here. The longest ones are like feet long. Right now, you're seeing cables that are only As we get into more cables and longer cables, we don't know if our equipment can pull them.
My gosh, we're going to be down the road a couple of blocks stringing the cables out, it's just going to present a whole new set of problems for us, but like here, why we'll just kind of have to work our way through them. Nobody had ever done this before anywhere in the world, pre-assemble these cables like this. So what we're doing here is we're cutting new ground. The next objective after the cable stays are built up is to take a configuration of cables like this and thread them through something called a wedge plate.
And a wedge plate is the device that enables us to anchor the cable stays to the structural steel of the bridge, and that's what will ultimately hold the bridge in place. It's kind of like threading 46 needles at one time. We're trying to line up 46 individual holes and thread all 46 of these through at one time.
The alignment of the individual cables as they pass through the wedge plate is critical. We want the cable to be perfectly perpendicular to the surface of the wedge plate. We also want the cable to be centered in its hole. The weight of the structure is carried by the cables. That load is transferred from the cable to the anchor assembly by these little jaw devices which are called wedges.
And they do this by small teeth that are cut into the wedges. These teeth bite through the epoxy coating into the steel of the strand, itself. They're small, but they're mighty. These wedges here have to be equally spaced around the cables to ensure a proper fitting when they stress the cable out on the bridge. If you get two of them to one side and you cause a big gap over here, they'll bite the cable incorrectly and could actually kink it or cut it, then you wouldn't have the strength from that cable, so each individual wedge gets special treatment.
You know, we look at each and every one of them and make sure that they are set right. If the problem of assembling the stays has been solved, that still leaves another: The solution here is to move very, very slowly, both on the ground and in the air. It takes three cranes to lift the stay: When the banana pipe is just above its bed, the crew begins to move it into position. Each stay has to fit perfectly into an anchorage slot. There's only a fraction of an inch to spare. When the stay is finally secured on top of the tower, other workers at the bottom turn their attention to each end.
This is what knits the bridge together. To pull the stays tight, special jacks called rams are then brought in. It costs thirteen hundred dollars a month to rent just one. But they're the only tools that can do the job. Every time the cables are tightened, it takes four rams. The cables have to be stressed in pairs, one ram on both ends of each cable. First the end of the stay is inserted into a guide pipe, then each ram is installed far below the top of the tower at the stay's anchorage point.
The cable is fed through, the ram grips it and pulls it tight, twelve inches at a time. As the ram tightens the cable, the amount of tension is carefully monitored. Each stay is tensioned to a carefully calculated degree, tight enough to support the deck and loose enough to flex in the wind. When another summer has passed, and autumn is painting the river banks orange, the surrounding countryside waits expectantly for the bridge and another harvest.
Autumn is the time of reckoning for every farmer. Here, the grain is golden in more ways than one. It's the coin of the realm. But even a fine harvest won't bring financial security to local towns. Too few people work on farms these days and too many farmers are in debt. Instead, the hope of a place like Alton is to become a more prosperous suburb of St. Louis, a bedroom community with charm.
A fine place to raise children, dogs and property values. And to keep the cash flowing, a prime tourist attraction as well, with reminders of Mark Twain's America, when Alton was at the pinnacle of its fame and fortune. But to make Alton great again will take more than echoes of the past.
Alton needs a modern bridge for a modern age, and everyone knows it. Today a class is taking a field trip to see for themselves. A model of the bridge has been set up on the banks of the river overlooking the site. What we're trying to do here is build a brand new bridge to replace that old bridge you see in the background here.
And do you all know how narrow that is and how bumpy it is? This is what the new bridge is going to look like where it crosses the middle of the river. Now there's more of the bridge on either end of it that's not shown, but this will be the main part and it'll be four lanes wide, so it'll carry at least twice as much traffic as that bridge and it'll also have a bicycle lane, so you can ride your bicycles back and forth across it.
It's going to be kind of neat to ride over the river on your bicycle. Will we have to pay higher taxes? No, you will not have to pay higher taxes to drive this bridge. Where the money comes from this bridge is every time your mother and father buys gasoline at the filling station, they pay a little bit of tax on every gallon. And right now I believe in Illinois it's about sixteen cents per gallon of whatever you pay goes into a fund to build bridges and roads and that's how all our bridges and roads are paid for in the whole country.