Kap Shui Mun Bridge

Kap Shui Mun Bridge
汲水門大橋

Kap Shui Mun Bridge, with Ma Wan in the foreground
Carries 6 lanes of roadway (upper)
2 MTR rail lines, 2 lanes of roadway (lower)
Crosses Kap Shui Mun
Locale Lantau and Ma Wan
Other name(s) KSMB
Maintained by Tsing Ma Management Limited: operation and maintenance contractor for the Tsing Ma Control Area; under contract to the Highways Department of the Government of the Hong Kong[1]
Characteristics
Design Double-decked cable-stayed bridge
Total length 750 metres (2,460 ft)
Width 32.5 metres (107 ft)
Longest span 430 metres (1,410 ft)
Clearance below 47 metres (154 ft)
History
Opened May 22, 1997
Kap Shui Mun Bridge
Traditional Chinese 汲水門大橋
Simplified Chinese 汲水门大桥

The Kap Shui Mun Bridge (KSMB) 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 used for motor vehicles and the lower deck used for both vehicles and the MTR. It has a main span of 430 metres (1,410 ft) and an overall length of 750 metres (2,460 ft). It spans the Kap Shui Mun marine channel between Ma Wan and Lantau and has a vertical clearance of 47 metres (154 ft) above sea level. The bridge was completed in 1997.

Structural information

Main span 430 m (1,410 ft)
Side spans 2 80 m (260 ft) spans each side
Lantau Approach Span 70 m (230 ft)
Ma Wan Viaduct 503 m (1,650 ft)
Overall length 1,323 m (4,341 ft)
Height of towers 150 m (490 ft)
Navigation clearance 47 m (154 ft)

The total length of the Kap Shui Mun Bridge includes a 70-metre (230 ft) approach span on the Lantau side. There is a column in each of the back spans of the cable stayed bridge, making four 80-metre (260 ft) spans, adding to the 430-metre (1,410 ft) main span. This makes the total length 820 metres (2,690 ft). The 503-metre (1,650 ft) Ma Wan Viaduct was constructed under the same contract as the KSMB. The viaduct connects the KSMB to the Tsing Ma Bridge, forming the Lantau Link, which was built to provide access to the new airport.[2] The navigation clearance of 47 metres (154 ft) is part of the reason that the H-shaped towers are 150 metres (490 ft) tall.

The Kap Shui Mun Bridge is not symmetrical, in that the 160-metre (520 ft) back span length (2 80-metre (260 ft) spans) is less than half of the main span length (which would be 215 metres (705 ft)). To provide the balance that symmetry will normally provide, part of the bridge has a composite structure. The center 387 metres (1,270 ft) 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.[3]

Because the lower deck carries both rail and traffic, the cross section is designed as a Vierendeel truss. 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 Vierendiel design.[3]

Along with the Tsing Ma Bridge and Ting Kau Bridge, it is closely monitored by the Wind and Structural Health Monitoring System (WASHMS).

Stay cables
Number 8 X 22 = 176
Total length of stay cables 11 km (6.8 mi)
Movement
Vertical, at midspan 470 mm (19 in)
Lateral, at midspan 155 mm (6.1 in)
Longitudinal, at Pier 1 320 mm (13 in)

Concrete strength of towers: Grade 50/20 or 50MPa

See also

References

  1. Hong Kong Factsheet: Transport
  2. Highways Department of the Government of the Hong Kong Special Administrative Region. "Lantau Link project page". Retrieved 2007-06-16.
  3. 3.0 3.1 Leonhardt, Andrä und Partner, Consulting Engineers VBI, GmbH. "Kap Shui Mun Bridge project page". Retrieved 2007-06-16.

External links

Wikimedia Commons has media related to Kap Shui Mun Bridge.

Coordinates: 22°20′39.3″N 114°3′19.3″E / 22.344250°N 114.055361°E

Kap Shui Mun Bridge
Preceded by
Ma Wan Viaduct
Kap Shui Mun Bridge Succeeded by
North Lantau Highway