The Kap Shui Mun Bridge (KSMB) in Hong Kong, part of

Lantau Link The Lantau Link, formerly known as the Lantau Fixed Crossing, is a roadway in Hong Kong forming part of Route 8 linking Lantau Island to Tsing Yi, from which other roads lead to the urban areas of Kowloon and the rest of the New Territories ...

of Route 8, is one of the longest

cable-stayed bridge A cable-stayed bridge has one or more ''towers'' (or ''pylons''), from which cables support the bridge deck. A distinctive feature are the cables or stays, which run directly from the tower to the deck, normally forming a fan-like pattern o ...

s in the world that transports both road and railway traffic, with the upper deck used for motor vehicles and the lower deck used for both vehicles and the MTR. It has a main span of and an overall length of . It spans the

Kap Shui Mun Kap Shui Mun () or Throat Gates (historically spelled Capsuimoon) is the 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 nor ...

marine channel between

Ma Wan Ma Wan is an island of Hong Kong, located between Lantau Island and Tsing Yi Island, with an area of .Lantau Lantau Island (also Lantao Island, Lan Tao) is the largest island in Hong Kong, located West of Hong Kong Island and the Kowloon Peninsula, and is part of the New Territories. Administratively, most of Lantau Island is part of the Islands Dis ...

and has a vertical clearance of above

sea level Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardised g ...

. The bridge was completed in 1997.

Structural information

The total length of the Kap Shui Mun Bridge includes a approach span on the Lantau side. There is a column in each of the back spans of the cable stayed bridge, making four spans, adding to the main span. This makes the total length . The Ma Wan Viaduct was constructed under the same contract as the KSMB. The viaduct connects the KSMB to the

Tsing Ma Bridge Tsing Ma Bridge is a bridge in Hong Kong. It is the world's 16th-longest span suspension bridge, and was the second longest at time of completion. The bridge was named after the two islands it connects, namely Tsing Yi and Ma Wan. It has tw ...

, forming the Lantau Link, which was built to provide access to the new airport. The navigation clearance of is part of the reason that the H-shaped towers are tall. The Kap Shui Mun Bridge is not symmetrical, in that the back span length (two spans) is less than half of the main span length (which would be ). To provide the balance that symmetry will normally provide, part of the bridge has a composite structure. The center of the main span uses a steel-concrete composite to make the structure lighter. The back spans and the rest of the main span are concrete. Using the lighter steel cross section in the majority of the main span serves to equalize the horizontal forces on the towers and balance the bridge. Because the lower deck carries both rail and traffic, the cross section is designed as a

Vierendeel truss A truss is an assembly of ''members'' such as beams, connected by ''nodes'', that creates a rigid structure. In engineering, a truss is a structure that "consists of two-force members only, where the members are organized so that the assembl ...

. This means that there are no diagonal members in the cross section and that vehicles and rail cars drive through the openings provided by the Vierendeel design. Along with the

and

Ting Kau Bridge Ting Kau Bridge is a long cable-stayed bridge in Hong Kong that spans from the northwest of Tsing Yi Island and Tuen Mun Road. It is near the Tsing Ma Bridge which also serves as a major connector between the Hong Kong International Airport ...

, it is closely monitored by the Wind and Structural Health Monitoring System (WASHMS). Concrete strength of towers: Grade 50/20 or 50MPa

Crane strike

The bridge has a height restriction of 41 metres for vessels passing underneath. On 23 October 2015, a barge attempted to pass under the bridge with a broken-down crane that could not be lowered. The crane had a maximum height of 43 metres, but was tilted slightly to 41 metres. The bridge has an actual clearance of 47 metres, but potentially due to the high tide and wave action, the crane struck the bridge and damaged its underside. The Tsing Ma Bridge has a higher height clearance of 53 metres but a source said the captain of the tugboat towing the barge may have opted to take Kap Shui Mun to save time. The strike triggered the Ship Impact Detection System to issue an alarm and both the road and railway were shut down immediately, severing Lantau Island and the airport from the city from about 7:40 pm to 10:00 pm. The government's contingency plan to implement emergency ferry service between Tsuen Wan and Tung Chung failed as the ferry operator took almost two hours to ready the service. Some travelers attempted to reach the airport via the Discovery Bay Ferry Pier, although many missed their flights. The

Highways Department Highways Department is a department of the Hong Kong Government responsible for developing Hong Kong's road and railway network as well as road maintenance. History The department was previously an office within the former Civil Engineering De ...

inspected the bridge and found that only the inspection platform rails were damaged by the collision, and that the structural integrity of the bridge was not jeopardised. In the days following the incident there were calls in local media for the government to build a second link to the airport. In fact, such a link was already under construction: the

Tuen Mun–Chek Lap Kok Link The Tuen Mun–Chek Lap Kok Link (, abbreviated as TM–CLKL) is a road project in the New Territories, Hong Kong. It comprises two elements: the "Northern Connection" and the "Southern Connection". The Northern Connection comprises an undersea tu ...

road tunnel was being constructed as part of the

Hong Kong–Zhuhai–Macau Bridge The Hong Kong–Zhuhai–Macau Bridge (HZMB) is a bridge–tunnel system consisting of a series of three cable-stayed bridges, an undersea tunnel, and four artificial islands. It is both the longest sea crossing and the longest open-sea fixe ...

project. This opened in 2020.

References

External links

*
Yokogawa Bridge project page
{{HK routes, r8; Bridges completed in 1997 Double-decker bridges Bridges in Hong Kong Route 8 (Hong Kong) Road-rail bridges Railway bridges in Hong Kong Cable-stayed bridges in Hong Kong Tsuen Wan District Vierendeel truss bridges

Structural information

Crane strike

See also

References

External links