How long is the Golden Gate bridge?
San Francisco Bay and the Pacific Ocean are connected by the Golden Gate Bridge.Both U.S. Route 101 and California State Route 1 cross the strait on their way to Marin County.One of the most well-known symbols of San Francisco and California is the bridge.It was originally designed by an engineer.The American Society of Civil Engineers declared it a Wonders of the Modern World.[7]
The Golden Gate Bridge is the most photographed bridge in the world according to the Frommer's travel guide.It was the longest suspension bridge in the world at the time of its opening in 1937, with a main span of 4,200 feet and a total height of 746 feet.10
The only way to get between San Francisco and Marin County before the bridge was built was by boat.A regularly scheduled ferry service began in the 1840s for the purpose of transporting water to San Francisco, and began as early as 1820.[2]
The Golden Gate Ferry Company, a Southern Pacific Railroad subsidiary, was the largest ferry operation in the world by the late 1920s.Once for railroad passengers and customers only, Southern Pacific's automobile ferries became very profitable and important to the regional economy.The ferry crossing between the Hyde Street Pier in San Francisco and the Sausalito Ferry Terminal in Marin County took 20 minutes and cost $1.00 per vehicle.The price was reduced to compete with the new bridge.The trip from the San Francisco Ferry Building took 27 minutes.
The bridge would connect San Francisco to Marin County.The largest American city still served by ferry boats is San Francisco.The city's growth rate was below the national average because it did not have a permanent link with communities around the bay.Many experts said that a bridge could not be built across the 6,700-foot (2,000-metre) strait, which had strong, swirling tides and currents, with water 372 ft (113 m) deep at the center of the channel.According to experts, blinding fogs and ferocious winds would prevent construction and operation.[15]
The idea of a bridge over the Golden Gate was first proposed in 1916 in a San Francisco Bulletin article by a former engineering student.San Francisco's City Engineer estimated the cost at $100 million, which was impractical for the time.He asked if the bridge could be built for less.One who responded was an ambitious engineer and poet who had designed a railroad bridge across the Bering Strait for his graduate thesis.The scale of the new project was not known at the time.The central suspension segment was promised to be built for $17 million, which is equivalent to $404 million today.[2]
The local authorities agreed to proceed only after they were assured that the design would be changed and that they would get input from experts.Recent advances in metallurgy made a suspension-bridge design the most practical.[2]
In Northern California, he spent more than a decade drumming up support.The bridge faced opposition from many sources.The Department of War was worried about the bridge.The entrance to one of the main harbors was feared to be blocked by a ship collision or sabotage.Local workers were demanded to be favored for construction jobs.The Southern Pacific Railroad, one of the most powerful business interests in California, opposed the bridge as competition to its ferry fleet and filed a lawsuit against the project, leading to a mass boycott.[2]
In May 1924, Colonel Herbert Deakyne held the second hearing on the Bridge on behalf of the Secretary of War in a request to use federal land for construction.On behalf of the Secretary of War, Deakyne approved the transfer of land needed for the bridge structure and leading roads to the "Bridging the Golden Gate Association" and both San Francisco County and Marin County.The automobile industry supported the development of roads and bridges to increase demand for automobiles.There are no comments at this time.
The bridge's name was first used in 1917.O'Shaughnessy is the city engineer of San Francisco.The Golden Gate Bridge and Highway District Act was passed by the state legislature in 1923, creating a special district to design, build and finance the bridge.San Francisco and most of the counties along the North Coast of California joined the Golden Gate Bridge District despite residents opposing the bridge's construction.[22]
The overall design and construction of the bridge was overseen by the chief engineer.The responsibility for much of the engineering and architecture fell on other experts because he had little experience with cable-suspension designs.The initial design proposal was not acceptable from a visual standpoint.Leon Moisseiff was the engineer of the Manhattan Bridge in New York City.[ 24]
The overall shape of the bridge towers, the lighting scheme, and Art Deco elements were designed by Irving Morrow, a relatively unknown residential architect.Morrow chose the International Orange color over other possibilities, including the US Navy's suggestion that it be painted with black and yellow stripes to ensure visibility by passing ships.[15][25]
Senior engineer Charles Ellis was the principal engineer of the project.The basic structural design was created by Moisseiff, who introduced his "deflection theory", in which a thin, flexible roadway would flex in the wind, greatly reducing stress on the bridge towers.Although the Golden Gate Bridge design has proved sound, a later Moisseiff design, the original Tacoma Narrows Bridge, collapsed in a strong windstorm soon after it was completed, because of an unexpected aeroelastic flutter.Ellis was tasked with designing a "bridge within a bridge" in the southern abutment to avoid the need to demolish Fort Point, a pre–Civil War masonry fortification viewed, even then, as worthy of historic preservation.He built a steel arch over the fort to carry the roadway to the bridge's southern anchorage.[28]
Ellis had no engineering degree but was a professor of engineering at the University of Illinois.He earned a degree in civil engineering from the University of Illinois and spent the last twelve years of his career as a professor.The standard textbook of the time was written by him.Ellis did a lot of technical work on the bridge, but he didn't get any credit in his lifetime.Ellis was fired in 1931 and replaced by a man who was supposedly for wasting too much money sending telegrams back and forth to Moisseiff.Ellis, obsessed with the project and unable to find work elsewhere during the Depression, continued working 70 hours per week on an uncompensated basis, eventually turning in ten volumes of hand calculations.[29]
Despite being largely responsible for the final form of the bridge, the contributions of his collaborators were downplayed.He was credited with being the person most responsible for the design and vision of the bridge.The contributions of the others on the design team were not appreciated until much later.The Golden Gate Bridge District gave Ellis major credit for the design of the bridge after issuing a report on 70 years of stewardship.
The Golden Gate Bridge and Highway District was incorporated in 1928 as the official entity to design, construct, and finance the bridge.After the Wall Street Crash of 1929, the District was unable to raise the construction funds, so it lobbied for a $30 million bond measure.The bonds were approved by the people of the affected counties.The construction budget at the time was $27 million.The District was unable to sell the bonds until the founder of Bank of America agreed to buy the entire issue in order to help the local economy.[2]
On January 5, 1933, construction began.The project cost more than $35 million and was completed ahead of schedule and under budget.The Golden Gate Bridge construction project was carried out by a subsidiary of Bethlehem Steel Corporation founded by Howard H. McClintic and Charles D. Marshall.
The head of the project remained, and he was responsible for day-to-day construction.A graduate of the University of Cincinnati, he placed a brick from the demolished McMicken Hall in the south anchorage before the concrete was poured.The use of safety nets beneath the construction site saved the lives of many ironworkers.On February 17, 1937, ten construction workers were killed when the net failed under the stress of a scaffold that had fallen.When the bolts that were connected to the track were too small, the platform that was attached to it collapsed.The net gave way after the platform fell into it.Slim Lambert, the foreman, was one of two workers who survived the 200 foot fall into the icy waters.Nineteen people who were saved by the net over the course of construction became members of the Half Way to Hell Club.[35]
The project opened on May 27, 1937.The Bridge Round House diner is located in the southeastern end of the Golden Gate Bridge.The Bridge Round House, an Art Deco design by Alfred Finnila, has been popular for many years as a starting point for various commercial tours of the bridge and an unofficial gift shop.In 2012 the diner was renovated and the gift shop was removed to make way for a new shop in the plaza.[37]
The Assistant Civil Engineer of California Alfred Finnila oversaw the entire iron work and half of the bridge's road work.Jack Balestreri's death in April 2012 made all the workers involved in the original construction dead.
The bridge was closed on December 1, 1951, after a windstorm revealed swaying and rolling instabilities.The bridge was retrofitted with bracing that connected the lower two sides of the bridge.The bracing stiffened the bridge deck in order to resist the types of twisting that destroyed the Tacoma Narrows Bridge in 1940.40
The bridge had a concrete deck.Salt carried by fog or mist can cause concrete spalling.The original bridge deck was replaced with 40% lighter and stronger steel panels over the course of a year.The outside curb lane width was 11 feet instead of 10 because the roadway was widened by two feet.The deck replacement cost over $68 million and was the bridge's greatest engineering project.[41]
The bridge- opening celebration lasted for a week.The day before vehicle traffic was allowed, 200,000 people crossed on foot or roller skates.On opening day, the mayor and other officials rode the ferry to Marin, then crossed the bridge in a motorcade past three ceremonial "barriers" to get to the Highway District.The song "There's a Silver Moon on the Golden Gate" was chosen to commemorate the event.The poem is on the Golden Gate Bridge.The President pushed a button in Washington, D.C. to start vehicle traffic over the Bridge at noon.There was a small riot in the Polk Gulch area as the celebration got out of hand.There were weeks of civil and cultural activities.There is a statue near the bridge that was moved in 1955.[17]
Pedestrians were allowed to cross the Golden Gate Bridge in May 1987 as part of the 50th anniversary celebrations.Ineffective crowd control meant the bridge became congested with 300,000 people, causing the center span to flatten out under the weight.Although the bridge is designed to flex in that way under heavy loads, and was estimated not to have exceeded 40% of the yielding stress on the suspension cables, bridge officials stated that pedestrian access was not being considered for the 75th anniversary on Sunday, May.[47]
The Golden Gate Bridge was the longest suspension bridge in the world until 1964.It has the second-longest main span in the Americas after the Verrazzano-Narrows Bridge in New York City.The total length of the Golden Gate Bridge is 8,981 feet.48
The Golden Gate Bridge's towers were the tallest on a suspension bridge until 1993 when they were surpassed by the Mezcala Bridge.
The weight of the roadway is hung from two main cables and 250 pairs of vertical suspender ropes.The main cables go over the two main towers.27,572 strands of wire are used to make each cable.The total length of galvanized steel wire is 80,000 miles.Each of the bridge's two towers has 600,000 rivets.[49]
When the Bay Area Rapid Transit system was being planned, the engineering community had differing opinions about the feasibility of running train tracks north to Marin County over the bridge.The bridge's suspension section was found to be able to support service on a new lower deck.In July 1961, one of the bridge's consulting engineers disagreed with their conclusion.In January 1962, the bridge's board of directors appointed an engineering review board to analyze all the feasibility reports.In 1962, the review board concluded that running BART on the bridge was not advisable.[52]
The first design of Joseph Strauss was rejected because of its Aesthetics.He added details to outline the bridge's cables and towers after re-submission of his bridge construction plan.In 1999, it was ranked fifth on the List of America's Favorite Architecture by the American Institute of Architects.
International orange is the color of the bridge.The consulting architect Irving Morrow chose the color because it enhances the bridge's visibility in fog.[57]
The bridge was originally painted with red lead primer and a lead-based topcoat.In the 1960's, a program was started to improve the protection of the bridge by stripping the original paint and painting it with zinc silicate primer and vinyl topcoats.Air-quality reasons have led to the use of acrylics.The program was completed in 1995 and is now maintained by 38 painters.The painting of the bridge is ongoing.60
The bridge is marked on most maps and signs between U.S. Route 101 and California State Route 1.The bridge isn't part of California's Highway System.Route 101 goes from the approach to the Golden Gate Bridge to a point in Marin County.The Golden Gate Bridge, Highway and Transportation District is in charge of the section of highway that crosses the bridge.
The median barrier is moved a lot to conform to traffic patterns.Four of the six lanes run south on weekday mornings.Four lanes run north on weekday afternoons.During off-peak periods and weekends, traffic is divided into three lanes.[62]
Between 1968 and 2015, opposing traffic was separated by plastic pylons, resulting in 16 deaths from 128 head-on crashes.On October 1, 1983, the speed limit on the Golden Gate Bridge was reduced from 50 to 45 mph.In March 2005, the Bridge Board of Directors committed to finding funding to complete a $2 million study prior to the installation of a barrier.Installation of the resulting barrier was completed on January 11, 2015, following the longest private vehicle traffic closure in the bridge's history.The cost to purchase and install the new barrier system is $30.3 million.It was 63 and 65.
The bridge has walkways on either side of the traffic lanes and is popular with pedestrians and bicyclists.The railings between the walkways and the traffic lanes were added in 2003 in order to prevent bicyclists from falling into the road.66
The Golden Gate Bridge carries about 112,000 vehicles a day.[67]
During the day, the main walkway is open for use by both pedestrians and bicycles, but only for the remaining daylight hours.The eastern walkway is only open to bicyclists in the evening and overnight when it is closed to pedestrians.During the hours when the eastern walkway is not open, bicyclists are only allowed on the western walkway.[68]
Two public transportation agencies provide bus service across the bridge.The Marin Headlands Express bus line has Saturday and Sunday service.The southern end of the bridge is accessible from 5 am to midnight.The Marin Airporter offers service across the bridge between Marin County and San Francisco International Airport.72
The Golden Gate Bridge Welcome Center is located on the San Francisco side of the bridge, next to the parking lot.It opened in time for the bridge's 75th anniversary.There is a cafe, outdoor exhibits, and restroom facilities nearby.The H. Dana Bower Rest Area and Vista Point are on the Marin side of the bridge.75
Animals such as harbor seals and sea lions can be found under and around the bridge.Three species of whales that had been absent in the area for a long time have reappeared recently.Researchers studying recovery/(re)colonizations in the vicinity of the bridge have encouraged stronger protections and recommended that the public use a local whale watching operator.[78]
The Golden Gate Bridge toll was 50 cents per car when it opened in 1937.In 1950 it was 40 cents each way, then 25 cents in 1955.In 1968, the bridge was only used to collect tolls from the south, with the toll amount going back to 50 cents in 2020.81
The last of the construction bonds were retired in 1971 with $35 million in principal and nearly $39 million of interest raised from bridge tolls.By 1991, the toll was $3.00, which is equivalent to $5.7 in 2020.81
In 2002, the bridge began accepting tolls via the electronic toll collection system, with $4 for users and $5 for those paying in cash, which is equivalent to $5.76 and $7.19 in 2020.The Golden Gate Bridge, Highway and Transportation District recommended a corporate sponsorship program to address its operating deficit.The District promised that the proposal, which it called a "partnership program", would not include changing the name of the bridge.In October 2007, the Board voted unanimously to seek additional revenue through toll increases.In 2008 the District increased the toll amounts to $5 for users of the system and $6 for those who pay in cash.81
In an effort to save $19.2 million over the next 10 years, the Golden Gate District voted in January of 2011.The toll taker elimination occurred in March.Over the course of eight years, the cost savings have been revised to $19 million.The Golden Gate District implemented license plate tolling and a one-time payment system for drivers to pay before or after crossing the bridge.Twenty-eight positions were eliminated.[85]
The toll for drivers who use the one time payment system was raised from $6 to $7 in April of this year.Motor vehicle traffic remains toll free.For vehicles with more than two axles, the toll rate was $7 per axle for those using license plate to Tolling or the one time payment system, and $6 per axles for FasTrak users.The discounted toll of $4 is equivalent to $4.37 in 2020 and must have been taken advantage of by drivers who had Fastrak.The Golden Gate Transportation District planned to increase the toll by 25 cents in July 2015, and then 25 more cents each of the next three years.[86]
Congestion pricing was approved by the Golden Gate Bridge District board in March of 2008.The Bay Area was able to meet the federal requirement for the funds thanks to this decision.The grant required the toll to be in place by September 2009.There are 89 and 90 items.
The congestion pricing program was ended in August of 2008 in favor of metered parking along the route to the bridge.[94]
The Golden Gate Bridge is the most used suicide site in the world.The deck is about 75 m above the water.jumpers hit the water at around 75 mph (120 km/h; 30 m/s) after a four second fall.Impact trauma is the cause of death for most.About 5% survive the initial impact but die in the cold water.95
After years of debate and an estimated more than 1,500 deaths, suicide barriers, consisting of a STAINLESS steel net extending 20 feet from the bridge and supported by structural steel under the walkway, began to be installed in April.Construction was expected to take four years at a cost of $200 million.In December of last year, it was reported that the suicide prevention net had fallen two years behind schedule because the lead contractor had been sold.The Golden Gate Bridge net's completion date was set in December of 2019.In 98 and 99.
The Golden Gate Bridge was designed to protect it from high winds.There were only three times when the bridge was closed because of weather: on December 1, 1951, December 23, 1982 and December 3, 1983.An anemometer has been placed on the west side of the bridge to measure wind speeds.One of the towers had an anemometer on it.