Monday, 15 October 2018

Golden Gate Bridge

Golden Gate Bridge 

GoldenGateBridge-001.jpg

The Golden Gate Bridge is a suspension bridge spanning the Golden Gate, the one-mile-wide (1.6 km) strait connecting San Francisco Bay and the Pacific Ocean. The structure links the American city of San FranciscoCalifornia – the northern tip of the San Francisco Peninsula – to Marin County, carrying both U.S. Route 101 and California State Route 1across the strait. The bridge is one of the most internationally recognized symbols of San Francisco, California, and the United States. It has been declared one of the Wonders of the Modern World by the American Society of Civil Engineers.
The Frommer's travel guide describes the Golden Gate Bridge as "possibly the most beautiful, certainly the most photographed, bridge in the world."[8][9] At the time of its opening in 1937, it was both the longest and the tallest 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).

Design

South tower seen from walkway, with Art Deco elements
Strauss was chief engineer in charge of overall design and construction of the bridge project.However, because he had little understanding or experience with cable-suspension designs,[22]responsibility for much of the engineering and architecture fell on other experts. Strauss's initial design proposal (two double cantilever spans linked by a central suspension segment) was unacceptable from a visual standpoint. The final graceful suspension design was conceived and championed by Leon Moisseiff, the engineer of the Manhattan Bridge in New York City.
Irving Morrow, a relatively unknown residential architect, designed the overall shape of the bridge towers, the lighting scheme, and Art Deco elements, such as the tower decorations, streetlights, railing, and walkways. The famous International Orange color was originally used as a sealant for the bridge. The US Navy had wanted it to be painted with black and yellow stripes to ensure visibility by passing ships.
Senior engineer Charles Alton Ellis, collaborating remotely with Moisseiff, was the principal engineer of the project. Moisseiff produced the basic structural design, introducing his "deflection theory" by which a thin, flexible roadway would flex in the wind, greatly reducing stress by transmitting forces via suspension cables to 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 also 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 penned a graceful steel arch spanning the fort and carrying the roadway to the bridge's southern anchorage.
Below Golden Gate Bridge
Ellis was a Greek scholar and mathematician who at one time was a University of Illinois professor of engineering despite having no engineering degree. He eventually earned a degree in civil engineering from the University of Illinois prior to 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 the standard textbook of the time. Ellis did much of the technical and theoretical work that built the bridge, but he received none of the credit in his lifetime. In November 1931, Strauss fired Ellis and replaced him with a former subordinate, Clifford Paine, ostensibly 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 unpaid basis, eventually turning in ten volumes of hand calculations.
With an eye toward self-promotion and posterity, Strauss downplayed the contributions of his collaborators who, despite receiving little recognition or compensation, are largely responsible for the final form of the bridge. He succeeded in having himself credited as the person most responsible for the design and vision of the bridge. Only much later were the contributions of the others on the design team properly appreciated. In May 2007, the Golden Gate Bridge District issued a formal report on 70 years of stewardship of the famous bridge and decided to give Ellis major credit for the design of the bridge.
The height, depth, and length of the span from end to end, looking west
The Golden Gate Bridge at sunset, as seen from just north of Alcatraz Island

Structural specifications

On the south side of the bridge a 36.5-inch-wide (93 cm) cross-section of the cable, containing 27,572 wires, is on display.
Until 1964, the Golden Gate Bridge had the longest suspension bridge main span in the world, at 4,200 feet (1,300 m). Since 1964 its main span length has been surpassed by thirteen bridges; it now has the second-longest main span in the United States, after the 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 Golden Gate Bridge's clearance above high water averages 220 feet (67 m) while its towers, at 746 feet (227 m) above the water, were the world's tallest on a suspension bridge until 1993 when it was surpassed by the Mezcala Bridge, in Mexico.
The weight of the roadway is hung from 250 pairs of vertical suspender ropes, which are attached to two main cables. The main cables pass over the two main towers and are fixed in concrete at each end. Each cable is made of 27,572 strands of wire. The total length of galvanized steel wire used to fabricate both main cables is estimated to be 80,000 miles (130,000 km).
In 1961, BART completed a study that determined the bridge's suspension section was capable of supporting planned rapid transit rail service on a new lower deck.These plans were not followed out.
The bridge has approximately 1,200,000 total rivets.[citation needed]

Aesthetics

The color of the bridge is officially an orange vermilion called international orange. The color was selected by consulting architect Irving Morrow because it complements the natural surroundings and enhances the bridge's visibility in fog. Aesthetics was the foremost reason why the first design of Joseph Strauss was rejected. Upon re-submission of his bridge construction plan, he added details, such as lighting, to outline the bridge's cables and towers. In 1999, it was ranked fifth on the List of America's Favorite Architecture by the American Institute of Architects.
The bridge was originally painted with red lead primer and a lead-based topcoat, which was touched up as required. In the mid-1960s, a program was started to improve corrosion protection by stripping the original paint and repainting the bridge with zinc silicate primer and vinyl topcoats. Since 1990, acrylic topcoats have been used instead for air-quality reasons. The program was completed in 1995 and it is now maintained by 38 painters who touch up the paintwork where it becomes seriously corroded.

Wind

Since its completion, the Golden Gate Bridge has been closed because of weather conditions only three times: on December 1, 1951, because of gusts of 69 mph (111 km/h); on December 23, 1982, because of winds of 70 mph (113 km/h); and on December 3, 1983, because of wind gusts of 75 mph (121 km/h).
An anemometer, placed midway between the two towers on the west side of the bridge, has been used to measure wind speeds. Another anemometer was placed on one of the towers.

Seismic vulnerability and improvements

South approach sub-structure with seismic isolators (short black cylinders) added as part of the Seismic Retrofit Construction Project
Doyle Drive Replacement Project progress in October 2013
Modern knowledge of the effect of earthquakes on structures led to a program to retrofit the Golden Gate to better resist seismic events. The proximity of the bridge to the San Andreas Fault places it at risk for a significant earthquake. Once thought to have been able to withstand any magnitude of foreseeable earthquake, the bridge was actually vulnerable to complete structural failure (i.e., collapse) triggered by the failure of supports on the 320-foot (98 m) arch over Fort Point. A $392 million program was initiated to improve the structure's ability to withstand such an event with only minimal (repairable) damage. One challenging undertaking is completing this program without disrupting traffic. A complex electro-hydraulic synchronous lift system was custom built for construction of temporary support towers and a series of intricate lifts, transferring the loads from the existing bridge onto the temporary supports. This was completed with engineers from Balfour Beatty and Enerpac, accomplishing this task without disrupting day-to-day San Francisco commuter traffic. The retrofit was planned to be completed in 2012.
The former elevated approach to the Golden Gate Bridge through the San Francisco Presidio, known as Doyle Drive, dated to 1933 and was named after Frank P. Doyle, President and son of the founder of the Exchange Bank in Santa Rosa, and the man who, more than any other person, made it possible to build the Golden Gate Bridge. The highway carried about 91,000 vehicles each weekday between downtown San Francisco and the North Bay and points north. The road was deemed "vulnerable to earthquake damage", had a problematic 4-lane design, and lacked shoulders, and a San Francisco County Transportation Authority study recommended that it be replaced. Construction on the $1 billion replacement, temporarily known as the Presidio Parkway, began in December 2009. The elevated Doyle Drive was demolished on the weekend of April 27–30, 2012, and traffic used a part of the partially completed Presidio Parkway, until it was switched onto the finished Presidio Parkway on the weekend of July 9–12, 2015. As of May 2012, an official at Caltrans said there is no plan to permanently rename the portion known as Doyle Drive.
Comparison of the side elevations of the Golden Gate Bridge and some notable bridges at the same scale. (click for interactive version)
San Francisco with two bridges (Western section of Bay Bridge in the left background), Coit Tower (in background to the left of north tower), and Fort Mason (on the San Francisco waterfront in the background behind the north tower) from Marin

Burj Khalifa

Burj khalifa

Burj Khalifa.jpg


Construction of the Burj Khalifa began in 2004, with the exterior completed five years later in 2009. The primary structure is reinforced concrete. The building was opened in 2010 as part of a new development called Downtown Dubai. It is designed to be the centrepiece of large-scale, mixed-use development. The decision to construct the building is based on the government's decision to diversify from an oil-based economy, and for Dubai to gain international recognition. The building was originally named Burj Dubai but was renamed in honour of the ruler of Abu Dhabi and president of the United Arab Emirates, Khalifa bin Zayed Al Nahyan; Abu Dhabi and the UAE government lent Dubai money to pay its debts. The building broke numerous height records, including its designation as the tallest buildingin the world.
Burj Khalifa was designed by Adrian Smith, of Skidmore, Owings & Merrill, whose firm designed the Willis Tower and One World Trade Center. Hyder Consulting was chosen to be the supervising engineer with NORR Group Consultants International Limited chosen to supervise the architecture of the project. The design is derived from the Islamic architecture of the region, such as in the Great Mosque of Samarra. The Y-shaped tripartite floor geometry is designed to optimize residential and hotel space. A buttressed central core and wings are used to support the height of the building. Although this design was derived from Tower Palace III, the Burj Khalifa’s central core houses all vertical transportation with the exception of egress stairs within each of the wings. The structure also features a cladding system which is designed to withstand Dubai's hot summer temperatures. It contains a total of 57 elevators and 8 escalators.
At a certain point in the architectural and engineering process, the original Emaar developers ran into financial issues, and required more money and economic funding. Sheikh Khalifa, the ruler of the United Arab Emirates, granted monetary aid and funding, hence resulting in the changing of the name to "Burj Khalifa". The concept of profitability derived from building high density developments and malls around the landmark have proven successful. Its surrounding malls, hotels and condominiums in Downtown Dubai have generated the most considerable revenue from the project as a whole, while the Burj Khalifa itself made little or no profit.
Critical reception to Burj Khalifa has been generally positive, and the building has received many awards. There were complaints concerning migrant workers from South Asia who were the primary building labor force. These centered on low wages and the practice of confiscating passports until duties were complete. Several suicides were reported.


Former namesBurj Dubai
Record height
Tallest in the world since 2008[I]
Preceded byTaipei 101
General information
StatusComplete
TypeMixed-use
Architectural styleNeo-futurism
LocationDubai
Address1 Sheikh Mohammed bin Rashid Boulevard
CountryUnited Arab Emirates
Coordinates25°11′49.7″N55°16′26.8″E
Named forSheikh Khalifa
Construction started6 January 2004
Topped-out17 January 2009
Completed1 October 2009
Opened4 January 2010
CostUS$1.5 billion
OwnerEmaar Properties
Height
Architectural828 m (2,717 ft)
Tip829.8 m (2,722 ft)
Top floor584.5 m (1,918 ft)
Observatory555.7 m (1,823 ft)
Technical details
Structural systemReinforced concrete, steel, and aluminium
Floor count154 + 9 maintenance
Floor area309,473 m2(3,331,100 sq ft)
Lifts/elevators57
Design and construction
ArchitectAdrian Smith
Architecture firmSkidmore, Owings & Merrill
Structural engineerBill Baker
Main contractorSamsung C&T
Other information
Parking2 subterranean levels

Statue of Unity

Statue of Unity

एकता क प्रतिमा
StatueofUnity.png
The Statue of Unity is a monument in India dedicated to Indian independence movement leader Vallabhbhai Patel located in the Indian state of Gujarat. It will be located facing the Narmada Dam, 3.2 km (2.0 mi) away on the river island called Sadhu Bet near Vadodara in Gujarat. This statue will occupy over 20,000 square meters, and will be surrounded by a 12 square km artificial lake. It is the world's tallest statue with the height of 182 metres (597 ft). Sardar Vallabhbhai Patel Rashtriya Ekta Trust (SVPRET), a special purpose vehicle was established by the Gujarat government and the outreach programme was carried out across India starting December 2013.
Initially the total cost of the project was estimated to be about ₹3,001 crore(US$420 million) by the Indian government. Later Larsen & Toubrowon the contract in October 2014 for its lowest bid of ₹2,989 crore(US$420 million) for the design, construction and maintenance. The construction was started on 31 October 2014. The construction of statue was completed in mid-October, 2018. It will be inaugurated on 31 October 2018 by Prime Minister Narendra Modi.

Project[edit]

Statue of Unity under construction, January 2018
The monument statue of Vallabhbhai Patelis being constructed facing the Narmada Dam, 3.2 km away on the river island called Sadhu Bet. The total height of the statue from its base will be 240 metre consisting base level of 58 metre and statue of 182 metre. It is being constructed with steel framing, reinforced cement concrete and bronze coating. The statue will need 75000 cubic metres of concrete, 5700 metric tonne steel structure, 18500 tonne reinforced steel rods, 22500 tonne bronze sheets for construction. In the first phase, a bridge connecting the memorial to the main land, a memorial, visitor centre buildings, a memorial garden, a hotel, a convention centre, an amusement park, research centres and institutes is being constructed.
The Statue of Unity is being designed as a naturalistic and historically accurate representation of Sardar Patel, wearing characteristic garments, in a walking stance. Some highlights of this project:
  • Bronze cladding on the Statue.
  • Fast elevators to reduce transit time for visitors.
  • The three-level base of the Statue - exhibit floor, mezzanine and roof - will contain a Memorial Garden and a large continuous museum/exhibition hall, comprising exhibits that focus on the life and contributions of Sardar Vallabhbhai Patel.
  • The observation deck, situated at a height of around 500 ft from river bed, will accommodate up to 200 people at a time. It will provide visitors a panoramic view, enabling them to see the beautiful Satpura and Vindhyachal mountain ranges, the 212 km long Sardar Sarovar Reservoir, and the 12 km long Garudeshwar Reservoir. For the comfort of the visitors against high wind forces, a 400-ton Tuned Mass Damper system has been provided above the observation deck.
  • Access to the Statue via a 5 km boat ride.
  • A large modern canopied public plaza, overlooking the Narmada River and the Statue, comprising food stalls, ornate gift shops, retail kiosks and other amenities, that will provide visitors a well-rounded tourist experience.

Finance

The monument is being built on a PPP model, with most of the money raised by Gujarat Government. The Government of Gujarat has allotted ₹100 crore for the project in the budget for 2012-13 and ₹500 crore in 2014-15. In the 2014-15 Union Budget announced on 10 July 2014, ₹2 billion (US$28 million) have been allocated for the construction of the statue.

Construction 

A consortium of Turner Construction (project manager of Burj Khalifa), Michael Graves and Associates and Meinhardt Group, is supervising the project. It will take 56 months to complete the project; 15 months for planning, 40 months for construction and two months for handing over by the consortium.The total cost of the project was estimated to be about ₹2,063 crore (US$290 million) by the government. The tender bids for the first phase were invited in October 2013 and were closed in November 2013.
The then Chief Minister of Gujarat Narendra Modi, (currently the Prime Minister of India) laid the foundation stone of statue on 31 October 2013, the 138th birth anniversary of Sardar Vallabhbhai Patel. He along with L. K. Advaniannounced to the public that after completion of the project, it will be the tallest statue of the world.
Indian infrastructure company Larsen & Toubro won the contract on 27 October 2014 for its lowest bid of ₹2,989 crore (US$420 million) for the design, construction and maintenance. They commenced the construction on 31 October 2014 and is expected to complete it by 2018. In the first phase of ₹2,989 crore (US$420 million) project, ₹1347 crore are for the main statue, ₹235 crore for exhibition hall and convention centre, ₹83 crore for the bridge connecting the memorial to the main land and ₹657 crore for the maintenance of the structure for 15 years after its completion. Accenture provides digital media outreach programme.
The monument is designed by Ram V. Sutar.
The statue is near completion. It will be inaugurated on 31 October 2018 by Prime Minister Narendra Modi.

Statue of Unity is located in Gujarat
Statue of Unity
Location of construction site in Gujarat state
Coordinates21°50′16″N 73°43′08″E
LocationSadhu bet, Near Sardar Sarovar Dam, Garudeshvar weir, GujaratIndia
DesignerRam V. Sutar
TypeStatue
MaterialSteel framing, reinforced concrete, bronze coating[1]
Height
  • statue: 182 metres (597 ft)
  • including base: 240 metres (790 ft)
[1]
Beginning date31 October 2014; 3 years ago
Dedicated toSardar Patel
Websitewww.statueofunity.in