what materials is the golden gate bridge made of

Full Answer

Is the Golden Gate Bridge made of steel?

The bridge is 8,981 feet long (1.7 miles) and contains about 83,000 tons of steel. The total weight of the bridge is 887,000 tons. There are two towers that hold up the two steel cables anchoring the bridge. Also, there are approximately 80,000 miles of wire inside each of the two steel cables.

What kind of steel was used in the Golden Gate Bridge?

Galvanized steelGalvanized steel is a lighter-weight construction material than concrete, which makes it ideal for long-spanning bridges. Additionally, the production process has significantly improved over time. When the Golden Gate bridge was built in the 1930s, it used 83,000 tons of steel.

What makes the Golden Gate Bridge strong?

HONEYCOMB LEGS – STRONG BUT LIGHT This innovation introduced by the Golden Gate Bridge provided the strength to withstand the tremendous weight transferred to the tops of the towers by the cables, and also to resist horizontal loads due to wind and earthquakes.

Is the Golden Gate Bridge made of real gold?

Some visitors wonder why the bridge isn't gold, like made from actual gold (or at least gold painted). Others, like me, have long mistaken it for red. The color is actually called 'international orange' - a variation on the color used now for many astronaut jumpsuits. It was a beautiful accident.

How does the Golden Gate Bridge not rust?

The zinc protects the steel, because zinc corrodes more easily than steel. Zinc serves as a sacrificial metal, so the steel does not rust when zinc is present. On top of that zinc primer is a top coat of paint in the Golden Gate Bridge's signature color called International Orange.

How long will the Golden Gate Bridge last?

The bridge, like other infrastructure, has a lifespan. But Bauer and Mohn say with proper maintenance, the Golden Gate Bridge will endure. The retrofit project alone will buy the span another 150 years, Bauer estimated.

Why is Golden Gate red?

The Golden Gate Bridge has always been painted orange vermilion, deemed "International Orange." Rejecting carbon black and steel gray, Consulting Architect Irving Morrow selected the distinctive orange color because it blends well with the span's natural setting as it is a warm color consistent with the warm colors of ...

How much does Golden Gate Bridge cost?

Golden Gate Bridge Tolls RatesNumber of Axles (see chart)FasTrak TollLicense Plate Account & One-Time Payment2 Axles/ Motorcycles$8.40$8.803 Axles$25.20$26.404 Axles$33.60$35.205 Axles$42.00$44.003 more rows

How much did the Golden Gate Bridge cost in today's money?

Construction began on January 5, 1933. The project cost more than $35 million ($530 million in 2020 dollars), and was completed ahead of schedule and $1.3 million under budget (equivalent to $25.7 million today).

Why isn't the Golden Gate Bridge painted gold?

The military eventually gave its approval, but it wanted the bridge to be covered in garish stripes. The Navy, concerned about visibility for passing ships in foggy conditions, pressed for black and yellow stripes to be painted on the Golden Gate Bridge.

Who owns Golden Gate Bridge?

Golden Gate Bridge, Highway and Transportation DistrictThe Golden Gate Bridge, Highway and Transportation District is a special district of the State of California which operates and maintains the Golden Gate Bridge and two unified public transit systems – Golden Gate Transit and Golden Gate Ferry – connecting the counties of Marin, Sonoma, San Francisco, and Contra Costa.

What are 5 facts about the Golden Gate Bridge?

5 Fun Facts About the Golden Gate BridgeThe bridge is actually not golden at all! It's a bright red-orange.It was named one of the Seven Wonders of the Modern World.It took four years to build.There are approximately 600,000 rivets in each of the bridge's towers.It's the most photographed bridge in the world.

How deep is the water under the Golden Gate Bridge?

At around 377 feet at its deepest point, the waters underneath the Golden Gate Bridge are bound to hold more than one ghostly tale from the past.

How much weight can the Golden Gate Bridge hold?

Bridge Deflection, Load Capacity The maximum upward deflection is 5.8 ft (1.8 m). The maximum transverse deflection, at center span is 27.7 ft (8.4 m). Live load capacity per lineal foot is 4,000 lbs (1,814.4 kg).

Why is the Golden Gate Bridge red and not gold?

The Golden Gate Bridge has always been painted orange vermilion, deemed "International Orange." Rejecting carbon black and steel gray, Consulting Architect Irving Morrow selected the distinctive orange color because it blends well with the span's natural setting as it is a warm color consistent with the warm colors of ...

How was the Golden Gate Bridge built underwater?

The barrier was made by sending concrete through funnels into wooden forms that were set in place by divers. Once the barrier was above water, workers called it a "giant bathtub." Next they filled the bottom portion of the barrier with concrete to serve as the foundation of the tower.

Why was the Golden Gate Bridge named after the Golden Gate Bridge?

The gateway to the San Francisco Bay was named Chrysopylae, or “Golden Gate”, by explorer John Charles Fremont Fremont in 1846 because I felt the Great Entrance would be advantageous for trade. Before the construction of the Golden Gate Bridge, people served by the ferries that travel between San Francisco and Marin to make the journey or to carry spring water from Sausalito to San Francisco.

How long did the Golden Gate Bridge last?

One of the most recognizable structures in the world, the Golden Gate Bridge was also at the time of its completion in 1937, the longest suspension bridge, and remained so for 27 years. Between its two tall towers of steel pass 1280 meters open water.

How many pillars are there on a suspension bridge?

The suspension bridges have two central pillars supporting the entire structure. From these pillars arise cables that support the weight of the roadway. Each pillar supports the weight of the section of bridge from the abutment to the end, and the section of bridge from the abutment to the middle of the bridge.

How much deformation is in the towers?

Transverse deformation of the towers: 0.32 m

How many times has the Golden Gate Bridge been closed?

In the last seven decades, endured countless earthquakes, including the devastating 1989 of 7.1 on the Richter scale. In fact, the bridge has been closed only three times in its history due to high winds.

What is the maximum deviation of the cross in the center?

The maximum deviation of the cross in the center includes: 8,4 m

What caused the road deck to deteriorate?

Over the years, salt and moisture from fog and the ocean has caused the road deck began to show signs of deterioration. In response, the largest engineering project since the construction of the bridge was carried out with the replacement of the original deck with lightweight concrete, steel orthotropic stronger asphalt and covered with epoxy

How is iron ore extracted?

Most iron ore is extracted through opencast mines [3] and mining causes air pollutions [4] . The process of extracting iron from haematite releases carbon dioxide that contributes to the greenhouse effect, carbon monoxide which is poisonous and sulfur dioxide which is also poisonous and causes acid rain [5].

What is coarse aggregate?

Coarse and fine aggregate are the filler materials for concrete, and commonly consist of gravel, pebbles, stones, and sand. Aggregates can be natural or man-made; natural aggregate comes from pits, rivers, lakes, and sea beds; where as one example of man-made aggregate can be gravel coming from quarries.

What materials were used to build the Golden Gate Bridge?

It is a suspension bridge that was built in 1937. The main materials used in building the Golden Gate Bridge include concrete, steel and paint.

How many people work on the Golden Gate Bridge?

Maintenance of the of the Golden Gate is a constant process but does not require a lot of labor. A crew of 33 painters and 16 iron workers continuously repair and monitor the bridge (Golden Gate Transportation District). Most of the embodied energy goes into chemical energy as new materials are made for the continual maintenance of the bridge. As mentioned earlier the painting is a continual process, where surveyors inspect the bridge and make note of places where the steel is corroding. 40,000 gallons of paint are needed each time and as we know there is a lot of embodied energy in the harvesting and processing of paint primary materials. Other maintenance projects like surveying and replacing corroded bolts, and support cables, are done on an as needed basis and systematically to prevent an accident but embody chemical, thermal, and mechanical energy in the production and replacing of said parts.

What is the first step in the product life cycle?

The first step in any product life cycle is, the harvesting of the raw materials to be processed into secondary materials. Of the three components analyzed, concrete was the most abundant by weight with 788,000 tons poured during the construction (Golden Gate Transportation District). The bridge’s foundations in both the land and sea were made from concrete as well as the providing structure on the steel spans for the road. The embodied energy in the harvesting and creation of concrete, is primarily thermal, mechanical and chemical energy. Concrete is can be made from different formulas but a common one is comprised of 41% gravel, 10% cement, 25% sand, 6% air, and 18% water (Penttala). Cement is the key ingredient because it acts as the bonding agent to harden concrete after it is poured. Cement is made up of a few different raw materials (limestone, sand, clay) and then processed by being baked and pulverized until correct consistency is met (Portland Cement Association). Studies on how much energy all these processes use to make cement have estimated that it takes about 1.4 GJ (giga-Joule) per ton of regular concrete and 2.5 GJ per ton of reinforced concrete (Penttala). Therefore, I estimate it took about 1,970,000 GJ of energy to make all the concrete for the Golden Gate. I used 2.5 GJ per ton because a mix of both were used in construction and these are more modern studies as well so the actual efficiencies could have been worse in the 1930’s.

How long did it take to build the Golden Gate Bridge?

The actual construction of the bridge took over four years but its unclear on how many people worked on the project at any given moment (Golden Gate Transportation District). The energy embodied during the construction was kinetic, thermal, electrical, chemical, and animate to power all the machines, ships, trucks, and workers used to assemble and transport the and parts of the bridge. Initially the foundations were built on both sides of the bay and a pier was made to access the tower foundations in the middle of the ocean. Kinetic and chemical energy was embodied in the removal of all the rock and sea bed, for the foundation of the anchorages and towers in the middle of the bay. They often used dynamite (chemical) and other crude but effective ways of removing chunks of land (PBS). Chemical energy was embodied in the boats, trucks, and machines that helped lift and move materials for the workers. Finally, thermal and electrical energy was embodied in all the welding and riveting of the entire structure. The amount energy exactly associated was very hard to extrapolate on though. The numbers of machines and workers was not well documented across all the contracts used in during the construction of the Golden Gate so coming up with estimates would be a little difficult. What I can assume is that this part of the life cycle embodies less energy, as there are fewer processes taken place and much of the work was animate, or done by humans. The amount of energy expendable by human force is not as great as the amount of energy used by fossil fuel machines to gather, produce, and transport the resources.

What happened to the concrete on the bridge?

In the entire history of the bridge, the only maintenance involving the bridges concrete was the removal of the cement paved deck of the bridge. This was done to the deck because the salt and moist air of from the ocean caused the concrete deck to deteriorate, thus a steel orthotropic deck was the choice to replace the old decrepit deck. Once the deck was removed, what most likely happened to the wasted concrete was that it was recycled and used as aggregate for more concrete somewhere else. Instead of dumping all the excess concrete in landfills, which was the common practice, the waste concrete was instead trucked to a processing facility where the wasted concrete was crushed into aggregate to be used in more concrete for another project.

How much does a bridge weigh?

Weight of Bridge, excluding anchorages and approaches, and including the suspended structure, main towers, piers and fenders, bottom lateral system and orthotropic redecking (1986) is 419,800 tons (380,800,000 kg *).

How many bundles of galvanized wire are there in a cable?

Number of bundles or strands of galvanized steel wire in one main cable is 61. Average number of galvanized steel wires in each of the 61 bundles is 452. Weight of both main cables, suspender cables, and accessories is 24,500 tons (22,200,000 kg).

How many feet are cable bands?

Main Cable bands are located every 50 feet along the main cables and the vertical suspender ropes are hung from the cable bands. Following the addition of the lower lateral bracing system in 1953 and 1954, it was found that the normal working of the Bridge, along with the addition of the lower lateral bracing system, had caused the main cable band bolts to lose as much as 50 percent of their specified tension. In 1954, the main cable bolts were re-tensioned by J. H. Pomeroy & Co., Inc and constituted the first application of calibrated impact wrenches for the tightening of cable band bolts.

Why is the downward deflection of a cable so high?

The maximum downward deflection is due to a condition with maximum live load on the center span, no live load on the side spans and maximum design temperature to elongate the main cables; and

What is the maximum transverse movement?

The transverse deflection is due to a sustained transverse wind load. The maximum transverse movement of 27.7 ft is based on the maximum allowable longitudinal movement of the wind locks at the support towers;

How far does the bridge move at midspan?

At midspan, the maximum downward deflection (or the distance the Bridge was built to move downward) is 10.8 ft (3.3. m). The maximum upward deflection is 5.8 ft (1.8 m).

How much weight is on a cable tower?

The load on each tower from main cables is 61,500 tons (56,000,000 kg).

What is the Golden Gate Bridge?

Golden Gate Bridge, suspension bridge spanning the Golden Gate in California to link San Francisco with Marin county to the north. Upon its completion in 1937, it was the tallest and longest suspension bridge in the world. The Golden Gate Bridge came to be recognized as a symbol of the power and progress of the United States, ...

Why is the Golden Gate Bridge important?

The Golden Gate Bridge came to be recognized as a symbol of the power and progress of the United States, and it set a precedent for suspension-bridge design around the world.

How long is the Verrazzano-Narrows Bridge?

The main span, 1,280 metres (4,200 feet) long, is suspended from two cables hung from towers 227 metres (746 feet) high; at midpoint the roadway is 81 metres (265 feet) above mean high water. Until the completion of the Verrazzano-Narrows Bridge in New York City in 1964, it had the longest main span in the world.

What is an encyclopedia editor?

Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. ...

When was the Verrazzano-Narrows Bridge opened?

The bridge opened to vehicular traffic on May 28, 1937, under budget and ahead of schedule. The main span, 1,280 metres (4,200 feet) long, is suspended from two cables hung from towers 227 metres (746 feet) high; at midpoint the roadway is 81 metres (265 feet) above mean high water. Until the completion of the Verrazzano-Narrows Bridge in New York City in 1964, it had the longest main span in the world.

How Long Is the Golden Gate Bridge?

A marvel of modern engineering, the Golden Gate Bridge is 1.7 miles long and 90 feet wide. Its 4,200-foot main span between the two towers was the longest for a suspension bridge until 1981, while its 746-foot towers made it the tallest bridge of any type until 1993.

Why was the Golden Gate Bridge closed?

The Golden Gate Bridge withstood the destructive Loma Prieta earthquake of 1989, and was closed to traffic only three times in its first 75 years due to weather conditions.

How deep was the first bridge support?

As a 1,100-foot trestle extended off the San Francisco side, divers plunged to depths of 90 feet through strong currents to blast away rock and remove detonation debris.

How much did Strauss buy in 1932?

Desperate, Strauss personally sought help from Bank of America President Amadeo Giannini, who provided a crucial boost by agreeing to buy $6 million in bonds in 1932. Construction commenced on January 5, 1933, with the excavation of 3.25 million cubic feet of dirt to establish the bridge’s 12-story-tall anchorages.

How many people died in the Halfway to Hell Club?

However, the near-spotless safety record was blemished when a scaffold fell and tore through the net in February 1937, resulting in the deaths of 10 workers.

When was the trestle of the trestle destroyed?

The trestle was damaged when it was struck by a ship in August 1933 and again amid a powerful storm late in the year, setting construction back five months.

When did the bridge and highway district get its bond money?

In November 1930 , a measure passed to allow for the issuance of $35 million in bonds to pay for the project. However, the Bridge and Highway District struggled to find a financial backer amid the difficulties of the Great Depression, a problem exacerbated by years of expensive legal proceedings.

Where Does The Name “Golden Gate” Come From?

What many people do not know is that the Golden Gate Bridge is so named because the body of water it passes over is called the Golden Gate Strait.

Why is the Golden Gate Bridge named after the bridge?

Therefore, the Golden Gate Bridge is simply named so because it is the bridge that passes over the Golden Gate Strait.

How much money did the Golden Gate Bridge cost?

This project not only wowed engineers, architects and the public alike but also was completed almost $2 million under budget at only $35 million. More than 2 billion cars have passed over the bridge and 10 million people travel to see the bridge every year.

How many miles of wire is on the Golden Gate Bridge?

In fact, the cables of the iconic bridge are actually made up of 27,000 individual pieces. Together, there are over 80,000 miles of wire on the Golden Gate Bridge. That’s enough wire to wrap around the earth more than 3.5 times.

Why was it harder to build the south tower of the Golden Gate Bridge?

The north tower was built first then the south one. It was harder to build the south tower because it was further out into the water.

How much did Joseph Strauss spend on the Golden Gate Bridge?

When Joseph Strauss took on the Golden Gate Bridge project, he was sure he could complete the project for $25 - 30 million. His plan was to build a 4,000-foot long bridge that would be an icon both in design and engineering.

How was the first wire laid?

The first wire was laid with the help of the Coast Guard. Shipping lanes in the Golden Gate Strait were closed down and Coast Guard ships dragged the wires from tower to tower through the ocean water. Cranes were then used to lift the wires up and attach them to the top of the towers.

How does the Golden Gate Bridge dance?

It is interesting how the Golden Gate Bridge ‘dances’ up and down depending on the temperature. Hot days with high temperature cause the metal to expand; steel cables elongate and the bridge’s deck lowers. This is especially visible in its central part.

How many pairs of cables are there on the bridge?

As for the vertical suspended cables, they tie the bridge’s deck to the main cables. There are 250 pairs of them; they are spaced 50 feet apart from each other and measure from 2 to 16 inches in diameter. All of the vertical ropes were replaced between 1972 and 1976.

What is the Golden Gate Bridge?

San Francisco’s Golden Gate Bridge is one of the most iconic bridges in the world. It is a so-called suspension bridge: the deck is supported by vertical cables attached to upper larger cables, which -in turn- extend between supporting towers and are anchored at the ends. The bridge’s construction begun in 1933 and gave chances ...

Why paint the red bridge?

In fact, the paint applied to the steel prevents both corrosion and rust that the air with high salt content in may cause .

When were suspension cables built?

On-site construction of the suspension cables began in 1935. All the bridge’s cables are made of galvanized carbon steel wires and they were laid by a ‘spinning’ technique. The two main cables alone account for 61,500 tons of weight load on the two 746-ft-tall (227 m) towers!