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Tsing Ma Bridge

Tsing Ma Bridge, Hong Kong

VSL Hong Kong (a subsidiary of the Bouygues Group) undertook the sub-contract (written and negotiated by their Commercial Manager Brett K. Jamieson) for the works which consisted of constructing all the superstructure concrete for the bridge. The sub-contract value was HK$ 300 million.

The works were divided up into three areas consisting of; construction of the two main tower pylons by the Slipform method including fabrication and Heavy Lifting of eight steel trusses being subsequently concreted and post-tensioned, construction of the four sets of approach piers by the Climbform method, and prestressing of the anchor blocks for the suspension cables.

The 196 m high pylons are of reinforced concrete incorporating some 42,100 m3 of concrete and 7,300 tonnes of reinforcing steel. The eight steel trusses were fabricated from over 980 tonnes of structural steel which later form part of the horizontal portal beams These also incorporate 550 tonnes of prestressing Due to the tight programme, height and dimensional complexity of the towers, a continuous 24 hours per day formwork system was adopted. To form the conical structure VSL worked closely with Gleitbau, the Austrian specialist slipform company. The use of the slipform system allowed a continuous average upward movement of 1.7 m per day to be obtained.

For temporary stabilisation of the towers, four steel trusses were installed between each of the two tower legs. These trusses also provided support for formwork, reinforcement and the post-tensioning ducts. The largest truss was 12 m high, 33 m long, 2.7 m wide and weighed 420 tonnes. Delivered to site by barge, each truss was off loaded to a low loader which delivered it onto sliding rails where VSL Heavy Lifting slid the trusses directly under the tower legs.

The trusses were then lifted vertically by VSL Group teamwork shapes the worlds longest road and rail suspension bridge.

The Lantau Fixed Crossing links Tsing Yi, Ma Wan and Lantau Islands by an elevated structure over 3 km long. The crossing is made up of three elements, namely the Tsing Ma Bridge, the Ma Wan Viaduct and the Kap Shui Mun Bridge. The Tsing Ma Bridge, which was the first main Airport Core Project under the Hong Kong Port & Airport Development Strategy (PADS) has been constructed by the Anglo-Japanese Consortium. The total contract value of this huge suspension bridge (2nd longest in the world) was just under 1 billion U.S. dollars.

It was in August 1992, that Mitsui-Costain J. V. awarded the sub-contract to VSL Hong Kong for carrying out a substantial portion of their allotted scope of works, with a site set-up and mobilization starting almost immediately. After two negotiated acceleration agreements, the first prepared for VSL by Brett K. Jamieson for HK$ 30 million and second by Gerard Muldoon for HK$14 million, both of whom were seconded to VSL by Dragages et Travaux Publics, These agreements allowed VSL’s on-site works to be complete by April 1994 .

Main Participants

Client: Hong Kong Government

Engineer: Mott MacDonald Hong Kong Ltd.

Main Contractor: Anglo-Japanese Consortium J.V. (Dorman Long - Costain - Mitsui)

Sub-Contractor: Mitsui - Costain Joint Venture

Work-Contractor: VSL Hong Kong Limited

40 m for the lowest and up to 157 m for the upper most truss. Lifting speeds of 20m per hour enabled installation in one day including horizontal translation of the upper two trusses. Each portal beam was concreted in 6 pours, has tendons contain 55 strands and required 1000 tonne jacks for stressing. Stressing was carried out from work platforms erected at the anchorages.

The Tsing Ma Bridge has four sets of approach piers which are reinforced concrete and between 54 and 58 m in height. VSL Climbform was chosen as it provided both high quality and compliance with the strict site safety standards.

Four Climbform Systems were used on the project, two of the systems being re-used three times on the piers of identical shape. Typical cycle time for the 4.1 m height concrete pours was 3 days, with only 6 men running two Climbforms concurrently.

On both Tsing Yi and Ma Wan, huge excavations were dug removing over 100,000 m3 of rock for the suspension bridge’s two anchor blocks. To ensure that each anchor block acts as a single unit 540 tonnes of post-tensioning tendons are used to tie each block together. VSL supplied and installed all of individually greased and sheathed strand. Typically, tendons are composed of 30 strands and 460 tonne jacks were used for primary stressing and subsequent re-stressing.

The Tsing Ma Bridge is probably the most impressive of all the Airport Core Projects. The size and scale of the structure has already led to international interest and reporting on its construction. VSL’s involvement in this mammoth task has reflected the belief that the VSL specialist systems and engineering experience in projects of this nature are to such a standard and level of quality, as to make VSL prime candidate for this type of work.

A clear navigable span of 1377 m will separate Tsing Yi and Ma Wan Islands.

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Thursday, May 04, 2006 04:48:15 AM