The Golden Gate Bridge is a suspension bridge spanning the Golden Gate, a mile wide (1.6 km) that connects San Francisco Bay and the Pacific Ocean. This structure connects the American city of San Francisco, California - the northern tip of the San Francisco Peninsula - to Marin County, carrying both Route 101 and California State Route 1 across the channel. This bridge is one of the most internationally recognized symbols of San Francisco, California, and the United States. It has been declared as one of the Wonders of the Modern World by the American Society of Civil Engineers.
Frommer's guide describes the Golden Gate Bridge as "the most beautiful bridge, certainly the most photographed, in the world." At the time of its opening in 1937, it was the longest and highest suspension bridge in the world, with a main span of 4,200 feet (1,280 m) and a total height of 746 feet (227 m).
Video Golden Gate Bridge
History
Ferry service
Before the bridge was built, the only practical short route between San Francisco and the current Marin County is by boat across the San Francisco Bay section. The ferry service began in 1820, with regularly scheduled services beginning in the 1840s for the purpose of transporting water to San Francisco.
The Sausalito Land and Ferry Company service, launched in 1867, eventually became the Golden Gate Ferry Company, a subsidiary of Pacific Railroad South, the world's largest ferry operation in the late 1920s. Once for rail and customer passengers, the Southern Pacific car ferry becomes very profitable and important to the regional economy. The ferry crossing between Hyde Street Pier in San Francisco and Sausalito in Marin County takes about 20 minutes and costs US $ 1.00 per vehicle, the price then reduced to compete with the new bridge. The journey from San Francisco Ferry Building takes 27 minutes.
Many want to build a bridge to connect San Francisco to Marin County. San Francisco is the largest American city still serviced mainly by ferries. Because it does not have a permanent relationship with people around the bay, the city growth rate is below the national average. Many experts say that the bridge can not be built in a width of 6,700 feet (2,042 m), which has strong currents and currents circling, with a water depth of 372 feet (113 m) in the center of the channel, and often strong. wind. Experts say that high winds and dazzling fog will prevent construction and operation.
Conception
Although the notion of a bridge covering the Golden Gate is not new, the final proposal was made in a 1916 San Francisco Bulletin article by former engineering student James Wilkins. San Francisco City Engineers estimated the cost of $ 100 million, which would be $ 2.12 billion in 2009, and not practical for the time being. He asked the bridge engineers if it could be built for less. One who answered, Joseph Strauss, was an ambitious engineer and poet who, for his graduation thesis, designed a 55-mile (89 km) railway bridge across the Bering Strait. By this time, Strauss had completed some 400 drawbridges - most of which were land - and nothing in the new project scale. Strauss's initial image is for a large cantilever on each side of the strait, connected by a central suspension segment, which Strauss promised could be built for $ 17 million.
The local authorities agreed to proceed only with the assurance that Strauss would change the design and receive input from some consultant project experts. The suspension bridge design is considered the most practical, due to recent advances in metallurgy.
Strauss spent more than a decade to rally support in Northern California. The bridge faces opposition, including litigation, from various sources. The War Department is concerned that the bridge will disrupt the vessel traffic. The Navy was worried that a ship's collision or sabotage to the bridge could block the entrance to one of its main ports. Unions are demanding assurances that local workers will be favored for construction work. The Southern Pacific Railroad, one of California's most powerful business interests, opposed the bridge as a competition for the fleet and filed a lawsuit against the project, which led to a massive boycott of ferry services.
In May 1924, Colonel Herbert Deakyne held a second hearing on the Bridge on behalf of the Secretary of War in a request to use federal land for development. Deakyne, on behalf of the Secretary of War, approved the transfer of land necessary for the structure of the bridge and led the way to "Bridging the Golden Gate Association" and both San Francisco and Marin County Districts, while awaiting further bridge plans by Strauss. Another ally is the burgeoning auto industry, which supports the development of roads and bridges to increase demand for cars.
The name of the bridge was first used when the project was initially discussed in 1917 by M.M. O'Shaughnessy, San Francisco city engineer, and Strauss. The name became official with the passage of the Golden Gate Bridge and the Highway District Law by the state legislature in 1923, creating a special district to design, build and finance bridges. San Francisco and most counties along the Northern Coast of California join the Golden Gate Bridge District, with the exception of being Humboldt County, whose population is opposed to bridge construction and the traffic it will generate.
Design
Strauss is the chief engineer responsible for the overall design and construction of the bridge project. However, since it has little understanding or experience with cable-suspension design, the responsibility for much engineering and architecture falls on other experts. Strauss's initial design proposal (two double cantilever ranges connected by the central suspension segment) is unacceptable from a visual point of view. The final graceful suspension design was conceived and championed by Leon Moisseiff, engineer from Manhattan Bridge in New York City.
Irving Morrow, the relatively unknown residential architect, designed the overall shape of the bridge tower, lighting scheme, and Art Deco elements, such as tower decorations, streetlights, fences, and walkways. The famous International Orange color was originally used as an insulator for the bridge. The US Navy wanted it painted with black and yellow stripes to ensure visibility with passing ships.
Senior engineer Charles Alton Ellis, working remotely with Moisseiff, is the project's principal engineer. Moisseiff produces the basic structure design, introducing its "deflection theory", a thin and flexible path will bend in the wind, greatly reducing stress by emitting power through the suspension cables to the bridge tower. Although the design of the Golden Gate Bridge has proven to be strong, the newer Moisseiff design, the original Tacoma Narrows Bridge, collapsed in a powerful windstorm soon after its completion, due to unexpected aeroelastic flutter. Ellis was also assigned to design a "bridge within the bridge" in the south, to avoid the need to destroy Fort Point, a pre-war stone fortress you were seen, even then, worthy of historical preservation. He wrote an elegant steel arch that stretched the fort and brought the road to the southern port of the bridge.
Ellis was a Greek scholar and mathematician who at one time was a professor of engineering at the University of Illinois despite not having a degree of engineer. He eventually earned a degree in civil engineering from the University of Illinois before designing the Golden Gate Bridge and spent the last twelve years of his career as a professor at Purdue University. He became an expert in structural design, writing a standard textbook at the time. Ellis does a lot of technical and theoretical work that builds bridges, but he does not receive any credit in his life. In November 1931, Strauss fired Ellis and replaced him with his former subordinate, Clifford Paine, as if wasting too much money sending telegram back and forth to Moisseiff. Ellis, obsessed with the project and unable to find work elsewhere during the Depression, continued to work 70 hours per week unpaid, eventually changing ten volumes of hand calculations.
With his eyes on self-promotion and posterity, Strauss played down the contributions of his collaborators who, despite receiving little recognition or compensation, were largely responsible for the final form of the bridge. He managed to make himself valued as the person most responsible for the design and vision of the bridge. Only long then the contributions of the others in the design team are well rewarded. In May 2007, the Golden Gate Bridge District issued an official report on 70 years of renowned bridge stewardship and decided to grant Ellis great credit for the design of the bridge.
Financial
The Golden Gate Bridge and Highway District, endorsed by the legislative act of California, was established in 1928 as an official entity to design, build, and finance the Golden Gate Bridge. However, after Wall Street Crash in 1929, the District was unable to raise development funds, thus lobbying for a $ 30 million bond size. Bonds were approved in November 1930, with votes in bridge affected areas. The construction budget at the time of approval is $ 27 million. However, the District was unable to sell bonds until 1932, when Amadeo Giannini, founder of Bank of America based in San Francisco, agreed on behalf of his bank to buy all the problems to help the local economy.
Construction
Construction began on 5 January 1933. The project cost more than $ 35 million, ($ 493 million dollars 2016) completed ahead of schedule and $ 1.3 million under budget. The construction project of the Golden Gate Bridge was carried out by McClintic-Marshall Construction Co., a subsidiary of Bethlehem Steel Corporation founded by Howard H. McClintic and Charles D. Marshall, both from Lehigh University.
Strauss remains the project's head, oversees day-to-day construction and makes some innovative contributions. A graduate from the University of Cincinnati, he placed a brick from McMicken Hall destroyed his alma mater in the southern port before the concrete was poured. He was innovating using a safety net moving under construction sites, which saved the lives of many unprotected iron workers. Of the eleven people killed by falling during construction, ten were killed on February 17, 1937, when the bridge was nearly completed when the net failed under the pressure of scaffolding that had fallen. The worker's platform attached to the hanger rolled over the track collapsed when the bolts connected to the track were too small and too heavy to bear. The platform crashed into the safety net, but it was too heavy and the net was detached. Two of the twelve workers survived the fall of 200 feet (61 m) into the cold waters, including a foreman of 37 years, Slim Lambert. Nineteen others who were rescued by nets during the construction process became their Half Way members to the Hell Club.
The project was completed and opened on 27 May 1937. The Bridge Round House restaurant is then incorporated at the southeastern end of the Golden Gate Bridge, adjacent to a renovated tourist plaza in 2012. The Bridge Round House, an Art Deco design by Alfred Finnila was completed in 1938 , has been popular for many years as a starting point for various commercial tours of bridges and unofficial souvenir shops. The restaurant was renovated in 2012 and the gift shop was later removed as a new official souvenir shop has been put in the adjacent square.
During the bridge work, California Civil Engineer Assistant Alfred Finnila has overseen all the ironworks of the bridge as well as half of the roadwork of the bridge. With the death of Jack Balestreri in April 2012, all the workers involved in the original construction are now dead.
Opening celebrations, 50th birthday, and 75th
The opening celebration of the bridge began on May 27, 1937 and lasted for one week. The day before vehicle traffic was allowed, 200,000 people crossed on foot or with roller skates. On the opening day, Mayor Angelo Rossi and other officials drove the ferry to Marin, then crossed the bridge in the motorcade through three "barrier" ceremonies, the last of which was the beauty queen blockade that required Joseph Strauss to present the bridge to the Highway District before letting him pass. The official song, "There's a Silver Moon at the Golden Gate", was chosen to commemorate the event. Strauss wrote a poem that is now on the Golden Gate Bridge entitled "Mighty Tasks Done." The next day, President Roosevelt hit the button in Washington, D.C. signifies the official start of vehicle traffic over the Bridge during the day. When the celebration was out of control there was a small riot in the town of Polk Gulch. The weeks of civil and cultural activities called "Fiesta" follow. Strauss's statue was moved in 1955 to a site near the bridge.
In May 1987, as part of a 50th anniversary celebration, the Golden Gate Bridge district again closed the bridge for vehicular traffic and allowed pedestrians to cross the bridge. However, this celebration attracts 750,000 to 1,000,000 people, and ineffective mass control means the bridge becomes overcrowded with about 300,000 people, causing the middle span of the bridge to flatten under its weight. Although the bridge is designed to flex it in that way under heavy loads, and is not expected to exceed 40% of the voltage generated from the suspension cables, the bridge officer states that uncontrolled pedestrian access is not considered part of the 75th anniversary on Sunday, May 27, 2012, due to additional law enforcement fees required "since 9/11".
Maps Golden Gate Bridge
Structural specifications
Until 1964, the Golden Gate Bridge had the longest suspension bridge range in the world, at 4,200 feet (1,300 m). Since 1964 the span of the main span has been exceeded by ten bridges; now has the second longest major span in the United States, after Verrazano-Narrows Bridge in New York City. The total length of the Golden Gate Bridge from abutment to abutment is 8,981 feet (2,737 m).
The permission of the Golden Gate Bridge above the mean water height is 220 feet (67 m) while its towers, at an altitude of 746 feet (227 m) above the water, are the highest in the world on suspension bridges until 1993 when the bridge was overpassed by the Bridge Mezcala, in Mexico.
The weight of the road is suspended from 250 pairs of vertical suspender ropes, attached to two main cables. The main cable passes through the two main towers and remains in the concrete at each end. Each cable is made of 27,572 pieces of wire. The total length of galvanized steel wire used to make both cables is estimated at 80,000 miles (130,000 km).
This bridge has about 1,200,000 total rivets.
Aesthetics
The bridge color is officially orange orange called international orange . The color was chosen by architect consultant Irving Morrow as it complemented the natural environment and increased the visibility of the bridge in the fog. Aesthetics are the main reason why Joseph Strauss's first design was rejected. After the redeployment of his bridge construction plans, he added details, such as lighting, to deciphering cables and bridge towers. In 1999, it was ranked fifth on the American Favorites' Favorite Architecture List by the American Institute of Architects.
The bridge was initially painted with red lead primers and a lead-based overcoat, which was touched as needed. In the mid-1960s, a program was initiated to improve corrosion protection by stripping the original paint and repainting bridges with zinc and vinyl silicate primers. Since 1990, acrylic topcoat has been used as a substitute for air quality reasons. The program was completed in 1995 and is now managed by 38 painters who touch the paint in which it becomes very rusty.
Traffic
Most maps and signposts mark the bridge as part of a concurrency between Flight 101 and the State Route of California 1. Although part of the National Highway System, the bridge is not officially part of the California Highway System. For example, under California Streets and Highways Code Ã,§ 401, Route 101 ends in "approach to the Golden Gate Bridge" and then proceeds to "point in Marin County opposite San Francisco". The Golden Gate Bridge, the Highway, and the Transport District have jurisdiction over the highway segment that crosses the bridge instead of the California Department of Transport (Caltrans).
Median median barrier between lanes was moved several times each day to adjust to traffic patterns. On a weekday morning, traffic flows mostly south to the city, so four of the six lanes run south. Conversely, on a weekday afternoon, four lanes run north. During the off-peak and weekend periods, traffic is divided by three lanes in each direction.
From 1968 to 2015, the opposite traffic was separated by small plastic poles, and during that time, there were 16 deaths resulting from 128 head collisions. To improve safety, the speed limit on the Golden Gate Bridge was reduced from 50 to 45 mph (80 to 72 km/h) on October 1, 1983. Despite discussions about the installation of a moving barrier since the 1980s, only in March 2005, the Board of Directors of the Board of Directors committed to seeking funding to complete the $ 2 million worth of studies needed before the installation of a moveable median barrier. Installation of the resulting barrier was completed on January 11, 2015, after 45.5 hours of closure for private vehicle traffic, the longest in the history of the bridge. The new barrier systems, including zippered trucks, cost about $ 30.3 million to buy and install.
Use and tourism
The bridge is popular with pedestrians and cyclists, and is built with sidewalks on both sides of the six-lane vehicular traffic. Initially, they were separated from the traffic lane by only the metal sidewalks, but a fence between the footpath and the traffic lane was added in 2003, primarily as a move to prevent cyclists from falling into the streets.
The main road is on the east side, and is open for use by pedestrians and bicycles in the morning until late afternoon during weekdays (5 am to 3:30 pm), and for pedestrians only for the rest of the day (up to 6 hours , or 9 pm during DST). The eastern path is provided for pedestrians on weekends (5 am to 6 pm, or 9 pm during DST), and is open exclusively to cyclists at night and night, when closed for pedestrians. The west path is only open for cyclists and only during the hours when they are not allowed on the eastern road.
The bus service across the bridge is provided by two public transport agencies: San Francisco Muni and Golden Gate Transit. Muni offers Saturday and Sunday services on the Marin Headlands Express bus line, and the Golden Gate Transit runs many bus lines throughout the week. The southern end of the bridge, near the toll plaza and parking lot, is also accessible daily from 5:30 am to midnight by the 28th Muni line. The Marin Airporter, a private company, also offers a cross-bridge service between Marin County and San Francisco International Airport.
The visitor center and souvenir shop, nicknamed "Pavilion Bridge", is located on the San Francisco side of the bridge, adjacent to the southeast parking lot. It opened in 2012, in time for the 75th anniversary celebration of the bridge. A cafe, outdoor exhibits and restroom facilities are located nearby. On the Marin side of the bridge, accessible only from the northern path, is H. Dana Bower Rest Area and Vista Point, named after the first landscape architect for California Division of Highways.
The land and waters beneath and around the bridge are home to a wide variety of wildlife such as bobcats and sea lions. Three species of cetaceans that have been absent in the area for years have shown recent recovery/(re) colonization around the bridge, and researchers are studying it to strengthen protection, about action by the public and recommend to watch whales from both bridges and nearby. , or use local whale watching operators.
Tolls
When the Golden Gate Bridge opened in 1937, the toll was 50 cents per car, collected in every direction. It was reduced to 40 cents each way in 1950, then lowered to 25 cents in 1955. In 1968, the bridge was changed to collect only tolls from traffic to the south, with the number of tolls resumed back to 50 cents.
The last of the construction bonds had been retired in 1971, with $ 35 million in principal and nearly $ 39 million in interest raised entirely from the bridge toll. Toll continues to be collected and then gradually raised; in 1991, it cost $ 3.
The bridge began receiving tolls through FasTrak's electronic toll collection system in 2002, with $ 4 of tolls for FasTrak users and $ 5 for those who pay cash. In November 2006, the Golden Gate Bridge, Highway and Transport District recommended a corporate sponsorship program for the bridge to overcome its operating deficit, which is projected at $ 80 million over five years. The district promised that a proposal, called a "partnership program," would not include renaming the bridge or putting up an advertisement on the bridge itself. In October 2007, the Council unanimously decided to suspend the proposal and seek additional income through other means, most likely to increase the toll. The district then increased the number of tolls in 2008 to $ 5 for FasTrak users and $ 6 to those who pay cash.
In an effort to save $ 19.2 million over the next 10 years, the Golden Gate District voted in January 2011 to eliminate all toll takers in 2012 and use only open highways. Furthermore, this is pending and taker removal done in March 2013. The cost savings have been revised to $ 19 million over an eight-year period. In addition to FasTrak, Golden Gate District implements the use of number plates (branded as "Pay-by-Plate"), as well as a one-time payment system for drivers to pay before or after their journey on the bridge. Twenty-eight positions are eliminated as part of this plan.
On April 7, 2014, the toll for FasTrak users is increased from $ 5 to $ 6, while tolls for drivers using tolling plates or a one-time payment system are raised from $ 6 to $ 7. Motor vehicle traffic, pedestrians and roads north remain toll free. For vehicles with more than two axles, toll fares are $ 7 per axle for those using tolling plates or a one-time payment system, and $ 6 per axle for FasTrak users. During peak hours, a carpool vehicle carrying two or more people and a motorcycle pays a discount of $ 4; drivers must have Fastrak to take advantage of this carpool rate. The Golden Gate Transport District then plans to increase the toll by 25 cents in July 2015, and then with another 25 cents every three years.
Jaming pricing
In March 2008, the Golden Gate Bridge District council approved a resolution to start congestion pricing at the Golden Gate Bridge, charging higher fees during peak hours, but up and down depending on traffic levels. This decision allows Bay Area to meet federal requirements to receive $ 158 million in federal transportation funds from the USDOT Urban Partnership grant. As a condition of the grant, the number of congestion will occur in September 2009.
The first results of the study, called Mobility, Access and Price Studies (MAPS), indicate that the congestion pricing program is feasible. Different pricing scenarios are considered to be presented in a public meeting in December 2008.
In August 2008, transport officials terminated a congestion pricing program supporting tariffs for metered parking along routes to bridges including on Lombard Street and Van Ness Avenue.
Problem
Suicide
The Golden Gate Bridge is the second largest suicide/suicide bridge in the world, after the Nanjing Yangtze River Bridge. The deck was about 245 feet (75 m) above the water. After a fall of four seconds, the jumpers hit the water at about 75 mph or about 120 km/h. Most jumpers die from trauma. About 5% of jumpers survived the initial impact but generally drowned or died of hypothermia in cold water.
After years of debate and over 1,500 deaths, suicide barriers began to be installed in April 2017. Construction will take about four years at a cost of over $ 200 million.
Wind
Since its completion, the Golden Gate Bridge has been closed due to weather conditions only three times: on 1 December 1951, due to wind gusts 69 mph (111 km/h); on December 23, 1982, due to the 70 mph (113 km/h) wind; and on December 3, 1983, due to gusts of 75 mph (121 km/h).
Anemometer, placed in the middle between two towers on the west side of the bridge, has been used to measure wind speed. Another anemometer is placed in one of the towers.
Vulnerability and seismic enhancement
Modern knowledge of the effects of earthquakes on structures causes the program to retrofit the Golden Gate to further withstand seismic events. The proximity of the bridge to San Andreas Fault puts it at a significant earthquake risk. Once considered capable of withstanding every possible earthquake, the bridge is completely vulnerable to complete structural failure (ie, collapse) triggered by a failure of support on the 320 foot (98 m) trajectory above Fort Point. The $ 392 million program was started to improve the structural ability to withstand such events with only minimal damage (can be fixed). One challenging task is to complete the program without disturbing the traffic. The complex electro-hydraulic sync removal system is tailor-made for the construction of temporary support towers and a series of elaborate lifts, transferring the load from existing bridges to temporary supporters. This was completed with engineers from Balfour Beatty and Enerpac, completing this task without disturbing the daily San Francisco commuter traffic. Retrofit is planned to be completed in 2012.
Former high approach to the Golden Gate Bridge through Presidio San Francisco, known as Doyle Drive, dated 1933 and named Frank P. Doyle, President and son of founder of Exchange Bank in Santa Rosa, and a person who, more than anyone else, Golden Gate Bridge. The highway carries about 91,000 vehicles every working day between downtown San Francisco and North Bay and heading north. The road was considered "vulnerable to earthquake damage", had a problematic 4-lane design, and had no shoulders, and a San Francisco District Transportation Authority study recommended that it be replaced. The $ 1 billion replacement construction, temporarily known as the Presidio Parkway, began in December 2009. The elevated Doyle Drive was destroyed on the weekend of 27-30 April 2012, and traffic used part of the completed Presidio Parkway, until it was transferred to Presidio Parkway finished on the weekend of 9-12 July 2015. In May 2012, an official at Caltrans said there was no plan to permanently rename the section known as Doyle Drive.
In popular culture
Source of the article : Wikipedia
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