The Golden Gate: Building an Impossible Bridge | The B1M

The Golden Gate: Building an Impossible Bridge | The B1M

In the 1920’s, long before the technologies
and advancements of today’s construction industry, a scheme was conceived to build
an impossible bridge across the Golden Gate Strait in California. Today that structure remains one of the world’s
most famous landmarks, but to truly appreciate the magnitude of this achievement, you need
to understand the bridge’s story. The Golden Gate Strait is a mile-wide channel
between San Francisco Bay and the Pacific Ocean. Many of northern California’s waterways
and mountain slopes run into San Francisco Bay and out to the ocean through this channel,
generating fast flowing, treacherous water. Up to the 1920’s, before the existence of
the bridge, the only way to cross the channel without taking an extended drive around the
bay, was by ferry. With the rise of cars and the growth of San
Francisco during the boom years, some 2.5M car trips a year were being made across the
water by 1929. The congestion led to growing calls for a
bridge to be attempted across the gap. Many felt such a feat was impossible. The channel’s
width, combined with a depth of over 372 feet (which is about 113 meters), and the harsh
environmental conditions were seen by many as too great to overcome. The city turned to the renowned bridge engineer
Joseph Strauss to consider the feasibility of such a scheme. Strauss had a high pedigree
in developing bridges but was infamously difficult to work with and had a reputation for creating
unattractive designs. His first proposal was widely disliked, and
the city’s authorities insisted that he could only proceed if he accepted design input
from others. That input came from Leon Moisseiff, Irving Morrow and Charles Alton Ellis, and
led to the development of the bridge as we know it today. Despite public support, gaining approval for
the bridge was not easy. The Golden Gate Bridge District, a holding company established to
construct and operate the bridge, faced opposition on a number of fronts. First they had to contend with the Southern
Pacific Railroad Company who operated the highly profitable ferry service. The operator
filed over 2,300 legal disputes in an attempt to prevent the bridge proceeding. Then they had to deal with the US Department
of War (as it was then known). They feared enemy planes bombing the bridge and collapsing
it into the strait, trapping navy ships in the bay. They also voiced concerns about vessels
colliding with the bridge during rough weather or in San Francisco’s infamous fog. The
Department of War even pushed for the bridge to be painted black with yellow stripes to
make it highly visible. Eventually, opposition gave way and plans
to develop the bridge proceeded. But just as that milestone had been reached, the financial
crash and great depression hit. Government funding evaporated and the bridge’s future
looked very uncertain. Determined to boost their economy with all
the benefits that the bridge could bring, the city’s authorities took matters into
their own hands. To secure funding, they proposed a bond measure secured against the properties
of their citizens in San Francisco and in the counties north of the bay. In a remarkable step, this decision was put
to a referendum and those Californian’s decided to proceed with the bond, despite
the widespread concerns about the bridge’s feasibility. The bridge’s USD $35M cost
and associated the finance fees were only paid off in 1971. This historic vote combined with an initial
USD $5M credit line from the Founder of the Bank of America enabled construction works
to commence. For all the struggle that had gone in up to this point, the hardest days
still lay ahead. Construction began in January 1933 with the
erection of the bridge’s towers. Each of these structures weighs 22,000 tonnes and
stands 746 feet tall; about 227 meters above the waters of the bay. They carry the entire
weight of the bridge. The first step was to create footings and
erect the north tower on the banks of Marin County. Construction of the south tower out
in the waters of the strait was far more challenging. First, the team built a temporary pier 1100
feet (or 335 meters) out into the ocean. This pier was destroyed twice during the works,
once by a storm and again by a steamer ship travelling in the fog. At the end of the pier, pilot bombs were dropped
down shafts to break up the rock under the sea bed. Seagulls swarmed over this operation
as stunned fish floated to the surface. With the bedrock loosened, the area was dredged
before the first underwater concrete pour. The area was then pumped out, and the remainder
of the concrete was dry poured. Simultaneously, the concrete anchorages that
the suspension cables would connect to were cast on either bank. The scale of concrete
being poured across the bridge site led to an on-site mixing plant being established.
With the southern footing in place, the steel south tower was erected. The next step was to suspend cables from the
bridge, a process which began in the summer of 1935. The cables used are in fact formed
of many individual wires – 27,572 wires to be precise, totalling some 80,000 miles
in length – enough to circle the globe three times over. With shipping lanes closed, the first wires
were dragged across the bay by a coastguard vessel and lifted by crane into the 150 tonne
curved cable cradles on top of each tower. A mid-span working platform was then slid
across. With this successfully achieved, the painstaking process of bundling and draping
strands of wire back and forth across the bridge began. Those at the top of towers worked for months
in 45mph winds, 746 feet above the water. Despite the hostile environment, productivity
was high and in one record-breaking shift a gang managed to spin 1,000 miles of wire
across the strait. As each wire crossed they were tightened at
their opposing end, eventually forming the bridges two main cables, each 3 feet wide
in diameter. Wooden pallets were then hung beneath the cables creating a catwalk for
workers to weave, compact and bond the wires before painting them to create a watertight seal. With the main cables in place, smaller vertical
cables were dropped down towards the water. Steel trusses were then attached to them,
creating the deck for the concrete roadway to be poured on. Throughout the construction process, many
workers fell from the bridge. A fall to the water from the road deck was fatal in most
instances, as impact speeds reached 75mph. Thanks to a then-innovative safety net, many
construction workers who fell were saved from hitting the water and became members of what
was dubbed the “half-way to hell club”. Tragedy struck in February 1937 when a paving
machine fell into the net taking a number of workers with it. The net collapsed under
the weight of the machinery and 10 people were killed in the incident. As construction progressed, so too did the
debate around what colour the bridge should be painted. It was the bridge’s orange steel
primer that struck a chord with the public and suited the Department of War’s requirements
for visibility. This shade is actually known as “international orange”; a stand-out
tone that is also used on NASA astronauts and American footballs. Just four years after construction work started
and with 600,000 steel rivets in place, the bridge was complete. It opened on 27 May 1937
with a pedestrian walk over day, cars followed 24 hours later. Traffic was stopped and the walk over day
repeated for the bridge’s 50th Anniversary in 1987. However, serious overcrowding occurred
and the bridge deflected by 10 feet, flattening out under the weight of the crowd. This extremely
dangerous incident has led officials to commemorate anniversaries in different ways ever since. The bridge has been a huge cultural and economic
success since its completion. Over 2 billion cars have now crossed the deck and the Golden
Gate has gone on to become an American icon, synonymous with the city of San Francisco.
Such status has led to increased security, particularly in the post-9/11 era. Steps have also been taken to better protect
the bridge from seismic activity, especially as technology and research in this area has
moved on from 1930’s understanding. The bridge sits between the San Andreas and Hayward
fault lines and is at risk of high-magnitude quakes. Energy dissipating devices have been
subtlety retrofitted and the towers supporting the approach ramps have been completely replaced. Maintenance of the bridge is an ongoing task
and falls to a team of 110 full time personnel who look after every aspect. In maintenance
terms, the bridge is very similar to an offshore oil platform. It must contend with ocean climates
and the onslaught of the elements this entails. Re-painting is done by specific areas, based
on corrosion monitoring, whilst an onsite steel fabrication shop is able to create replacement
components. Larger scale refits have taken place, including
a complete replacement of the suspension ropes in the 1970s and a new lighter steel road
deck in the 80s. Now 80 years old, the bridge remains one of
the single most important elements of US road infrastructure. A key piece of cultural and
construction heritage and an iconic symbol of what human engineers are truly capable of. If you enjoyed this video and would like to
get more from the definitive video channel for construction, subscribe to The B1M.

100 Replies to “The Golden Gate: Building an Impossible Bridge | The B1M”

  1. It's nice and very helpfull but the city is terrible. Not everyone or everywhere, just the driver's, the road's, and the piggly wiggly's.

  2. I crossed it twice a day for years. And have ridden my bike across it hundreds of times. It’s truly marvelous. ❤️

  3. Could you please elaborate on the challenges that were faced in constructing the "southern tower"? Great video! Very informative!

  4. Could you please elaborate on the challenges that were faced in constructing the "southern tower"? Great video! Very informative!

  5. Could you please elaborate on the challenges that were faced in constructing the "southern tower"? Great video! Very informative!

  6. Could you please elaborate on the challenges that were faced in constructing the "southern tower"? Great video! Very informative!

  7. A concise and enjoyable accounting of how America's greatest bridge survived enormous economic and engineering challenges. It was constructed in only four years, and smack in the middle of the Great Depression. Compare that to 14 years required for the recent construction of the much smaller Oakland extension of the Bay Bridge. That project went billions over budget and years behind schedule, and now there are complaints that is cables are rusting prematurely.

  8. 7:38 That would have sucked if the overcrowding of humans, on the anniversary date, led to the bridge's collapse. Phewww.

  9. I'm curious if this bridge had been built 50-75 years with it's exact material and design (I know probably the steel didn't exist 75 years prior.. but just for the sake of argument) if in 1906 it would of survived the quake of San Francisco. I'm curious if it being slightly aged and some rust (regardless of it's maintained year round work of painting) if it will last another quake equal or greater to 1906. the quake in 1989 was only a large moderate. not a great quake. so it had pretty much 0 affect on the bridge as far as damages went. it's a 113 years gone by. 1906 quakes happen about every 75-100 years. as a matter of fact a quake the size or even greater happened in 1880 in San Francisco. and one in 1862 I believe in Stockton. so.. yeah we're pretty much overdue for a huge quake

  10. Would like to see a vid on Roebbling Bridge, aka suspension bridge between Covington, Kentucky and Cincinnati, Ohio. Good story.

  11. Now in SF…. Transbay transit center takes twice as long to build, cost 4 times as much (adjusted) and broke after 2 weeks….zonks

  12. As a local these photos are amazing to see people just walking around on the bridge. You know the first person to drive across this bridge was the first mayor of Santa Rosa ca? Helped put together the blue prints for the bridge.

  13. My great Grandfather was one of the cable workers for the Golden Gate Bridge in the 30's. He also made the newspaper for his work on fixing the cables. I have photographs and the newspaper with his article in it.

  14. And now San Francisco is a haven of homelessness, street tents, public defecation & urination, hypodermic drug needles, pot holes, growing crime, rampant drug use, unaffordable housing, high taxes and corrupt politicians. ?

  15. Eric Holder openly claims there is nothing great about America. Does he know about the Golden Gate Bridge?

  16. They couldn’t build something like this, the scale, impressive beauty, and in 4 years today because everything known to the state of California causes cancer, birth defects and reproductive harm.

  17. it would have been 100% perfect if this was explained by an American. Who has NO accent. I bet some people are having a hard time understanding him. I am from California, San Francisco, I grew up in San Francisco and move during my college years. This guy is murdering the information of Golden Gate Bridge. I really wish an American should have explained the Golden Gate Bridge. This guy is not even from American, let along San Francisco, California. I resent this. No, I WILL NOT subscribe to you channel.

  18. Its almost $200 dollars to cross the dam bridge i live here and it seems to me the price raises every dam year! Another california scam to get money from everyone.My dad was a painter on Dumbarton bridge he said he freezes his ass off can you imagine GG.

  19. San Francisco is my home my love and my life, I love it even though it's hard to make friends and hard to get laid lol.

  20. I live about 45 mins away from the bridge, ive been there tons of times, i know ppl who have been living in the area and never walked or even crossed the bridge wtf

  21. And now, San Francisco is like a dumpster. I last visited it few months ago and it looked even worse than San Jose. Walking in union square would smell urine and see so many homeless. San Francisco gives out needles to drug users everyday. It even create a place for drug users to shoot up. It also gives monthly check payment to homeless for them to spend. It’s sad to see how San Francisco is turning into a dumpster.

  22. Shame on the video editor who is guilty of committing the video atrocity of BBC (Blow-up, Blur, Crop) the ~4:3 photos to fill the 16:9 frame. Doing "click to fill" may look OK on a computer screen (other than the unnaturally overly large images) but on a TV there is a loss of resolution and you are also altering/censoring the carefully composed and framed images by the historical photographers.

  23. what is so impossible about the GG bridge >>China is building bigger and longer bridges everyday and faster with better technologies than the GG bridge

  24. Weird to say but this bridge is sexy. Is also the best thing about SF if you are vistiing as a tourist. See the bridge but don't go to the city specially downtown. Belive me !

  25. Most Americans don't know that Lisbon, capital of Portugal, in Europe, has a similar bridge made by the same company. U can see here:

  26. Instead of wasting $200 million on a useless net that's slows people from jumping use that money to fix up the bridge its needs it bad

  27. You know what's messed up about the crash, how the value of property rockets through the roof while wages stay low, even that said though today there are in fact over 14 million people considered to be millionaires on the planet.

  28. “It took 4 years to build the most famous bridge on Earth”

    It’s taken 5 years to build the Starbucks right down the street!

  29. As a young kid in 1961 I used to sit on the shores of Alameda, CA (near NAS Alameda) and watch ships sail under the Golden Gate bridge. I used always wonder were they were going. Those were fun and simple days.

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