Tsing Ma Bridge
Encyclopedia
The Tsing Ma Bridge is a bridge
Bridge
A bridge is a structure built to span physical obstacles such as a body of water, valley, or road, for the purpose of providing passage over the obstacle...

 in Hong Kong
Hong Kong
Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour...

. It is the world's seventh-longest span suspension bridge
Suspension bridge
A suspension bridge is a type of bridge in which the deck is hung below suspension cables on vertical suspenders. Outside Tibet and Bhutan, where the first examples of this type of bridge were built in the 15th century, this type of bridge dates from the early 19th century...

, and was the second longest at time of completion. The bridge was named after two of the islands at its ends
Islands and peninsulas of Hong Kong
Hong Kong comprises the Kowloon peninsula and 263 islands over 500 m2, the largest being Lantau Island and the second largest being Hong Kong Island. Ap Lei Chau is one of the most densely populated islands in the world....

, namely Tsing Yi and Ma Wan
Ma Wan
Ma Wan is an island of Hong Kong, located between Lantau Island and Tsing Yi Island, with an area of 0.97 km². Administratively, it is part of Tsuen Wan District....

 . It has two decks and carries both road
Road
A road is a thoroughfare, route, or way on land between two places, which typically has been paved or otherwise improved to allow travel by some conveyance, including a horse, cart, or motor vehicle. Roads consist of one, or sometimes two, roadways each with one or more lanes and also any...

 and rail
Rail transport
Rail transport is a means of conveyance of passengers and goods by way of wheeled vehicles running on rail tracks. In contrast to road transport, where vehicles merely run on a prepared surface, rail vehicles are also directionally guided by the tracks they run on...

 traffic, which also makes it the largest suspension bridge of this type. The bridge has a main span of 1377 metres (4,518 ft) and a height of 206 metres (676 ft). The span is the largest of all bridges in the world carrying rail traffic.

The 41 metres (135 ft) wide bridge deck carries six lanes of automobile traffic, with three lanes in each direction. The lower level contains two rail tracks. There are also two sheltered carriageways on the lower deck for maintenance access and as backup for traffic when particularly severe typhoons strike Hong Kong. Though road traffic would need to be closed in that case, trains could still get through in either direction.

History

Construction of the bridge was carried out by a Costain
Costain Group
Costain Group plc is a British construction and civil engineering company headquartered in Maidenhead. It was part of the original Channel Tunnel consortium and is involved in Private Finance Initiative projects.-History:...

 / Mitsui
Mitsui
is one of the largest corporate conglomerates in Japan and one of the largest publicly traded companies in the world.-History:Founded by Mitsui Takatoshi , who was the fourth son of a shopkeeper in Matsusaka, in what is now today's Mie prefecture...

 / Trafalgar House
Trafalgar House (company)
Trafalgar House Public Limited Company was a British conglomerate with interests in property investment, property development, engineering, construction, shipping, hotels, energy and publishing...

 joint venture. Construction work of the bridge began in May 1992 and ended in May 1997. It cost HK$7.2 billion. The Lantau Link
Lantau Link
The Lantau Link, formerly known as the Lantau Fixed Crossing, is a series of infrastructures linking Hong Kong International Airport to the urban areas in Hong Kong. It was officially opened on 27 April 1997, and it opened to traffic on 22 May the same year.-Infrastructure:The Lantau Link is 3.5 km...

, of which the bridge is an integral part, was opened on April 27, 1997. The ceremony was inaugurated by the former British Prime Minister Margaret Thatcher
Margaret Thatcher
Margaret Hilda Thatcher, Baroness Thatcher, was Prime Minister of the United Kingdom from 1979 to 1990...

.

Operation

The Tsing Ma Bridge links Tsing Yi island on the east to Ma Wan island on the west over Ma Wan Channel
Ma Wan Channel
Ma Wan Channel is a channel between Ma Wan and Tsing Yi Island in Hong Kong. The north end of the channel is Ting Kau where it joins the Rambler Channel. To the west it joins with the Kap Shui Mun channel running to the south of Ma Wan, leading into Urmston Road. To the east it divides into the...

. It is part of the Lantau Link
Lantau Link
The Lantau Link, formerly known as the Lantau Fixed Crossing, is a series of infrastructures linking Hong Kong International Airport to the urban areas in Hong Kong. It was officially opened on 27 April 1997, and it opened to traffic on 22 May the same year.-Infrastructure:The Lantau Link is 3.5 km...

, which, with two long span bridges links the New Territories
New Territories
New Territories is one of the three main regions of Hong Kong, alongside Hong Kong Island and the Kowloon Peninsula. It makes up 86.2% of Hong Kong's territory. Historically, it is the region described in The Convention for the Extension of Hong Kong Territory...

 and Lantau Island
Lantau Island
Lantau Island , based on the old local name of Lantau Peak , is the largest island in Hong Kong, located at the mouth of the Pearl River. Administratively, most of Lantau Island is part of the Islands District of Hong Kong...

, and eventually leads to the Hong Kong International Airport
Hong Kong International Airport
Hong Kong International Airport is the main airport in Hong Kong. It is colloquially known as Chek Lap Kok Airport , being built on the island of Chek Lap Kok by land reclamation, and also to distinguish it from its predecessor, the closed Kai Tak Airport.The airport opened for commercial...

 on Chek Lap Kok
Chek Lap Kok
Chek Lap Kok was an island in the western waters of Hong Kong. Together with the smaller Lam Chau, it was leveled and merged via land reclamation into the platform for the current Hong Kong International Airport, which opened for commercial operations in 1998...

 via North Lantau Highway
North Lantau Highway
North Lantau Highway is part of Route 8 of Hong Kong, linking Hong Kong International Airport and Lantau Island with the rest of the territory. It is an expressway with three lanes in each direction for its entire length with full width hard shoulders for emergencies and breakdowns...

. The other bridge is the Kap Shui Mun Bridge
Kap Shui Mun Bridge
The Kap Shui Mun Bridge in Hong Kong is one of the longest cable-stayed bridges in the world that transports both road and railway traffic, with the upper deck for motor vehicles, and the lower deck for both vehicles and the MTR. It has a main span of 430 metres and an overall length of 750 metres...

 linking Ma Wan to Lantau Island over Kap Shui Mun
Kap Shui Mun
Kap Shui Mun or Throat Gates is a major channel, between Lantau Island and Ma Wan, in Hong Kong. It is part of major sea route along the coast of South China, from Victoria Harbour to the Pearl River. It joins north with Urmston Road...

. The two bridges are connected over Ma Wan by Ma Wan Viaduct
Ma Wan Viaduct
Ma Wan Viaduct is a viaduct built over Ma Wan, an island in the Hong Kong Special Administrative Region of the People's Republic of China. The viaduct connects the Tsing Ma Bridge and Kap Shui Mun Bridge, and is part of the Lantau Link and Route 8...

.

The Tsing Ma Bridge has been an important gateway to Lantau Island. It is Route 8 expressway, which connects the Lantau Link, the West Kowloon
West Kowloon
West Kowloon is a part of Kowloon, Hong Kong situated within the Yau Tsim Mong District. It is bounded by Canton Road to the east, Victoria Harbour to the west and the south, and Jordan Road to the north. Further to the north, the area extends to Tai Kok Tsui to the west of the West Kowloon...

 expressway, Cheung Sha Wan
Cheung Sha Wan
Cheung Sha Wan is an area between Lai Chi Kok and Sham Shui Po in New Kowloon, Hong Kong. It is mainly residential to the north and south, with an industrial area in between. Administratively it is part of Sham Shui Po District. The Sham Shui Po District includes Mei Foo as well as Lai Chi...

 and Shatin. The rail line is part of MTR
MTR
Mass Transit Railway is the rapid transit railway system in Hong Kong. Originally opened in 1979, the system now includes 211.6 km of rail with 155 stations, including 86 railway stations and 69 light rail stops...

's Tung Chung Line and Airport Express
Airport Express (MTR)
The Airport Express is one of the lines of the Mass Transit Railway serving Hong Kong. It links the principal urban areas of Hong Kong to Hong Kong International Airport and the associated AsiaWorld-Expo exhibition and convention centre....

.

The bridge, together with other highway, bridge and tunnel connections in the area, are part of the Tsing Ma Control Area
Tsing Ma Control Area
Tsing Ma Control Area is an area covering Lantau Link and related road networks in Hong Kong, including the Tsing Ma Bridge, Kap Shui Mun Bridge, Ma Wan Viaduct , Cheung Tsing Highway, Cheung Tsing Tunnel, Rambler Channel Bridge , Ting Kau Bridge...

 under the Tsing Ma Control Area Ordinance (Cap. 498) in Hong Kong Law. The control area has been managed by Tsing Ma Management Limited since opening. The control area's traffic management system was developed by Delcan Corporation of Toronto
Toronto
Toronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...

. Special regulations and by-laws are carried out in the area.

Along with the Ting Kau Bridge
Ting Kau Bridge
Ting Kau Bridge is a 1,177-metre long cable-stayed bridge in Hong Kong that spans from the northwest of Tsing Yi Island and Tuen Mun Road. It is adjacent to Tsing Ma Bridge which also serves as major connector between the Hong Kong International Airport on Lantau Island and the rest of Hong Kong....

 and Kap Shui Mun Bridge
Kap Shui Mun Bridge
The Kap Shui Mun Bridge in Hong Kong is one of the longest cable-stayed bridges in the world that transports both road and railway traffic, with the upper deck for motor vehicles, and the lower deck for both vehicles and the MTR. It has a main span of 430 metres and an overall length of 750 metres...

, the bridge is closely monitored by the Wind and Structural Health Monitoring System (WASHMS). Surveillance cameras are also installed over the bridge to record traffic conditions. The video is available at the government website. It is updated every two minutes.

Toll payable on the Lantau Link, of which Tsing Ma Bridge is part, for motor cycle, private car, public double-decked bus and heavy goods vehicle are HK$20, $30, $60 and $80 respectively, payable only for the direction from Lantau to Tsing Yi. The normal speed limit
Speed limit
Road speed limits are used in most countries to regulate the speed of road vehicles. Speed limits may define maximum , minimum or no speed limit and are normally indicated using a traffic sign...

 on the bridge is 80 km/h, subject to lowering in the event of road work or strong wind. Traffic may also be directed to the sheltered carriageways on the lower deck when there are very strong winds. There is no sidewalk
Sidewalk
A sidewalk, or pavement, footpath, footway, and sometimes platform, is a path along the side of a road. A sidewalk may accommodate moderate changes in grade and is normally separated from the vehicular section by a curb...

 on the Bridge. Parking is also prohibited on the bridge.

Wind tunnel testing

The objectives of the wind tunnel
Wind tunnel
A wind tunnel is a research tool used in aerodynamic research to study the effects of air moving past solid objects.-Theory of operation:Wind tunnels were first proposed as a means of studying vehicles in free flight...

 studies were to demonstrate the safety of the structure under construction and once completed, both with respect to aerodynamic stability
Flight dynamics
Flight dynamics is the science of air vehicle orientation and control in three dimensions. The three critical flight dynamics parameters are the angles of rotation in three dimensions about the vehicle's center of mass, known as pitch, roll and yaw .Aerospace engineers develop control systems for...

 as well as the possible effects of extreme typhoon wind speeds. A further objective was to provide dynamic response data at several key locations to compare with full scale data from the ongoing monitoring program, conducted by the Highways Department of Hong Kong.

A 1 to 80 scale section model of the deck in the erection stage, and a 1 to 400 scale full aeroelastic model of the entire bridge were constructed. It is a Monte-Carlo
Monte Carlo method
Monte Carlo methods are a class of computational algorithms that rely on repeated random sampling to compute their results. Monte Carlo methods are often used in computer simulations of physical and mathematical systems...

 simulation of the typhoon wind climate. The full model was tested in different stages of construction in turbulent boundary layer flow, complete with the local topography
Topography
Topography is the study of Earth's surface shape and features or those ofplanets, moons, and asteroids...

 in order to model the wind conditions at the site. The model tests identified critical stages of erection that allowed the construction schedule of the bridge to be tailored to avoid the typhoon season. The comparison of model test results and the full scale monitoring will assist engineers to better understand the behaviour of long span bridges in wind and to improve current design methods.

Major components

  1. Bridge tower foundations - one tower located on Wok Tai Wan
    Wok Tai Wan
    Wok Tai Wan was a bay on the northwest coast of Tsing Yi Island, Hong Kong. The beach in the bay was once nudist paradise. Its hardness to accessing the bay on foot, with high hills surrounded, or by small boat, with turbulence in the nearby sea, made it the idea place for nudists to swim and...

     of Tsing Yi side and the other on a man-made island 120 m from the coast of Ma Wan Island. Both towers are 206m above sea level and founded on relatively shallow bedrock. The towers are two-legged with trusses at intervals, in the form of portal beam design. The legs were constructed with high-strength concrete of 50 MPa (concrete grade 50/20) strength, using a slipform system in a continuous operation.
  2. Anchorages - the pulling forces in the main suspension cables is taken up by large gravity anchorages located at both ends of the bridge. They are massive concrete structures deeply seated on bedrock on the landside of Tsing Yi and Ma Wan island. The total weight of concrete used in the Tsing Yi anchorage is 200,000 tonnes and Ma Wan Anchorage is 250,000 tonnes.
  3. Main cables - The cables were constructed by an aerial spinning process. The process involved drawing wires from a constant-tension supply, and pulling loops of these wires from one anchorage to the other, passing a 500-tonne cast-iron saddle on top of each bridge tower seating the cable. A total of 70,000 nos. galvanised wires of 5.38 mm diameter were placed and adjusted to form the 2 nos. of 1.1 m diameter main cables.
  4. Suspended deck - The steelwork for the deck structure was fabricated in Britain
    United Kingdom
    The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

     and Japan
    Japan
    Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

    . After delivery, they were further processed and assembled in Dongguan
    Dongguan
    Dongguan is a prefecture-level city in central Guangdong province, People's Republic of China.An important industrial city located in the Pearl River Delta, Dongguan borders the provincial capital of Guangzhou to the north, Huizhou to the northeast, Shenzhen to the south, and the Pearl River to...

     of China into standard deck modules. A total of 96 modules, each 18 m long and about 480 tonnes in weight, were prepared. These deck modules were brought to the site by specially designed barges and raised into the deck position by a pair of strand jack
    Strand jack
    Strand jacks are jacks used to lift very heavy loads for construction and engineering purposes...

     gantries that could manoeuvre along the main cable.
  5. Approach span on Tsing Yi side - similar in form and cross-section to the suspended deck, but the approach span was supported on piers instead of cable-support. The first span was assembled on the ground and raised into position using strand jacks. Further erection then proceeded in cantilever in smaller sections, using derrick cranes stationed on the deck level. An expansion joint
    Expansion joint
    An expansion joint or movement joint is an assembly designed to safely absorb the heat-induced expansion and contraction of various construction materials, to absorb vibration, to hold certain parts together, or to allow movement due to ground settlement or earthquakes...

     which allowed for a maximum thermal movement of ± 835 mm was also provided and located inside the approach span section.

Tourism

Tsing Ma Bridge has become a favourite scenic spot as well as a famous landmark. In order to watch and get further information about it, one can go to the Lantau Link Visitor Centre and Viewing Platform which is located at the northwest corner of Tsing Yi Island, just next to the Bridge's Tsing Yi end. Pictures and the structure of the Lantau Link and Ting Kau Bridge are on display at the Centre. The Visitors Centre is opened from 10:00 am to 5:00 p.m. on weekdays (closed on Wednesday); from 10:00 am to 6:30 p.m. on Saturdays, Sundays and most of the public holidays. From the Scenery Viewing Platform, one can also see the Ting Kau Bridge
Ting Kau Bridge
Ting Kau Bridge is a 1,177-metre long cable-stayed bridge in Hong Kong that spans from the northwest of Tsing Yi Island and Tuen Mun Road. It is adjacent to Tsing Ma Bridge which also serves as major connector between the Hong Kong International Airport on Lantau Island and the rest of Hong Kong....

 and Kap Shui Mun Bridge
Kap Shui Mun Bridge
The Kap Shui Mun Bridge in Hong Kong is one of the longest cable-stayed bridges in the world that transports both road and railway traffic, with the upper deck for motor vehicles, and the lower deck for both vehicles and the MTR. It has a main span of 430 metres and an overall length of 750 metres...

. They are the other two bridges listed in the world's "Three Mosts" as well. Visitors can also have a different spot at the Airport Core Programme Exhibition Centre
Airport Core Programme Exhibition Centre
The Airport Core Programme Exhibition Centre, is housed in a single-storey distinctive white structure situated at 401 Castle Peak Road, Ting Kau, New Territories in Hong Kong. The exhibition centre is run by the Home Affairs Department for the Airport Core Programme often referred to as the Rose...

 located about 2 km north of the Bridge.

See also

  • List of buildings and structures in Hong Kong
  • List of longest suspension bridge spans
  • List of streets and roads in Hong Kong: Bridges
  • Tunnels and bridges in Hong Kong
    Tunnels and bridges in Hong Kong
    -Victoria Harbour crossings:-Tunnels on Hong Kong Island:-Tunnels in Kowloon:-Tunnels between Kowloon and the New Territories:-Tunnels in the New Territories:-Bridges:-See also:* Transport in Hong Kong...

  • Hong Kong-Zhuhai-Macau Bridge
    Hong Kong-Zhuhai-Macau Bridge
    The in-construction Hong Kong-Zhuhai-Macau Bridge is a series of bridges and tunnels that will connect the west side of Hong Kong to Macau and the Guangdong province city of Zhuhai, which are situated on the west side of the Pearl River Delta. The proposed link is expected to cost US$10.7 billion....


Further reading

  • Y. L. Xu, J. M. Ko and Z. Yu. "Modal analysis of tower-cable system of Tsing Ma long suspension bridge". Engineering Structures. Volume 19, Issue 10, October 1997, pp. 857–867.

External links

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