Tsing Ma Bridge

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Tsing Ma Bridge Traditional Chinese: 青馬大橋

Carries	6 lanes of roadway (upper) 2 MTR rail lines, 2 lanes of roadway (lower)
Crosses	Ma Wan Channel
Locale	Ma Wan Island amd Tsing Yi Island
Design	Double-decked suspension bridge
Longest span	1,377 metres (4,518 ft)
Width	41 metres (135 ft)
Opening date	April 27, 1997
Toll	HK$30 (cars)
Coordinates	22°21′05″N, 114°04′27″E

Tsing Ma Bridge is a bridge in Hong Kong, China. It is the world's sixth largest suspension bridge. The bridge was named after two of the islands in Hong Kong, namely Tsing Yi and Ma Wan . It has two decks and carries both road and rail traffic, which also makes it the largest suspension bridge of this type. The upper deck carries a dual three-lane carriageway and there are two tracks of railway and a two-lane emergency roadway in the lower deck for maintenance and the diversion of traffic during high winds. It has a main span of 1,377 metres (4,518 ft) (more than the famous Golden Gate Bridge in San Francisco) 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, 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 car traffic would need to be closed in that case, trains could still get through in either direction. Along with the Ting Kau Bridge and Kap Shui Mun Bridge, it is closely monitored by the Wind and Structural Health Monitoring System (WASHMS).

The Tsing Ma Bridge links Tsing Yi Island on the east to Ma Wan island on the west over Ma Wan Channel. It is part of the Lantau Link, which, with four long span bridges links the New Territories and Chek Lap Kok, where the Hong Kong International Airport is located. The other three bridges are the Ma Wan Viaduct which continues the route of the Tsing Ma Bridge, the Kap Shui Mun Bridge linking Ma Wan to Lantau Island over Kap Shui Mun, and the Ting Kau Bridge, linking Tsing Yi Island and Tuen Mun and Yuen Long, over Rambler Channel.

The rail line is part of MTR's Tung Chung Line and Airport Express.

Construction work of the bridge began in May 1992 and ended in May 1997. It cost HK$7.2 billion. The Lantau Link, 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.

Surveillance cameras were installed over the bridge to record traffic conditions. The video is available at the government website ^[1]. It is updated every two minutes.

Tsing Ma Bridge
Traditional Chinese:		青馬大橋
Mandarin
Mandarin	Hanyu Pinyin:	Qīngmǎ dàqiáo
	Wade-Giles:	Ch'ing1 ma3 ta4 ch'iao2
Cantonese
Cantonese	Jyutping:	cing1 maa5 daai6 kiu4

The Tsing Ma Bridge has been an important gateway to Lantau. It will become part of the planned Route 8 expressway, which will connect the Lantau Link, the West Kowloon expressway, Cheung Sha Wan and Shatin.

Tsing Ma Bridge by day (October 2004)

1 Five major components in its construction
2 The wind tunnel
3 As a tourist sight
- 3.1 Ways to get there
  - 3.1.1 To the bridge
  - 3.1.2 To the Visitor Centre and Viewing Platform
- 3.2 Operating hours of architectural lighting
4 Management
5 Tolls
6 Traffic speeds
7 Footnote
8 See also
9 External links

[edit] Five major components in its construction

Foundations and the construction of the bridge tower - one tower located on Wok Tai Wan 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.
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.
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.
Suspended deck - The steelwork for the deck structure was fabricated in Britain and Japan. After delivery, they were further processed and assembled in Dongguan 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 gantries that could manoeuvre along the main cable.
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 which allowed for a maximum thermal movement of ± 835 mm was also provided and located inside the approach span section.

[edit] The wind tunnel

The objectives of the wind tunnel studies were to demonstrate the safety of the structure under construction and once completed, both with respect to aerodynamic stability 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.

It is a 1 to 80 scale section model of the deck in the erection stage and 1 to 400 scale full aeroelastic model of the entire bridge. It is a Monte-Carlo 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 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.

[edit] As a tourist sight

A panoramic view of the Tsing Ma bridge (June 2006)

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 Visiting Centre is opened from 10:00 am to 5:00 p.m. on weekdays; 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 and Kap Shui Mun Bridge. 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 located about 2 km north of the Bridge.

There is no sidewalk on the Bridge. Parking is also prohibited on this gigantic Bridge.

[edit] Ways to get there

[edit] To the bridge

There are several ways to travel along the upper deck of the Bridge. The cheapest way is to take a bus running between the Hong Kong International Airport (or Tung Chung or Hong Kong Disneyland Resort as well) and the city. These Citybus and Long Win Bus routes have the route number prefixes "A", "E" and "R". (except route R8)

[edit] To the Visitor Centre and Viewing Platform

Only cars, taxis and private coaches can reach the Visitor Centre. Taxis can be caught at the nearest MTR station, Tsing Yi Station, which cost around HK$30. There are parking places for cars and coaches.

[edit] Operating hours of architectural lighting

There is night lighting which makes the bridge even more gorgeous. The operating hours of the lights are as follows:

Monday to Sunday: 6:00 p.m. to 12:00 midnight (October – February) and 7:30 p.m. to 12:00 midnight (March – September)

Special Event: 6:00 p.m. to 1:00 a.m. of the following day (October – February) and 7:30 p.m. to 1:00 a.m. of the following day (March – September)

[edit] Management

The bridge, together with other highway, bridge and tunnel connections, formed Tsing Ma Control Area under Tsing Ma Control Area Ordinance (Cap. 498) in Hong Kong Law. The control area has been managed by Tsing Ma Management Limited since its grand opening. The control area's traffic management system was developed by Delcan Corporation of Toronto. Special regulations and by-laws are carried out in the area.

[edit] Tolls

The double tolls of the Lantau Link for motor cycle, private car, public double-decked bus and heavy goods vehicle are HK$20, $30, $60 and $80 respectively.

[edit] Traffic speeds

There are speed restrictions on the bridge. The maximum speed limit is usually 80 km/h for automobiles. Such speed limit may be lowered upon roadwork or under strong wind. Traffic may also be directed to the sheltered carriageways on the lower deck when there are very strong winds.