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Sixty suspended bridge deck units assembled
Sixty steel deck units for the Tsing Ma Bridge have been assembled at a site in Shatian in Dongguan, southern China.
A total of 96 units are required for the suspended span, which measures 1,732 metres, including the 1,377-metre main span.
About 900 engineers, technicians, welders and other skilled workers are working on the assembly of these units, said Project Director of the Lantau Fixed Crossing Management Office, Highways Department, Mr K C Yeung,
On average, six or seven units are assembled at the site every month. Each unit weighs about 420 tonnes and the total weight of steel parts to be assembled will be around 40,000 tonnes.
Each unit is 18 metres long, 7.5 metres high and 41 metres wide.
The four-hectare site in Shatian is conveniently located by the Pearl River for easy loading and unloading.
"The main frames of the deck units are fabricated in the UK and Japan, while some ancillary components are produced in Australia and Korea," Mr Yeung said.
The parts are shipped to the site. They are cleaned and grit-blasted before being coated with anti-corrosive paint.
In a sub-assembly stage, the smallest units are bolted or welded together to form intermediate units. These are then similarly connected to become a single deck unit.
Mr Yeung noted that assembly work began in October 1993 with the arrival of the first batch of components. The last shipment is due to arrive this month.
"Deck units adjacent to each other are assembled to form 36-metre long "assembled units". The fit-up between these assembled units will be checked to avoid problems in fitting the units when erection takes place in Hong Kong," he said.
"Assembled units will then be transported by barges down the river to the Tsing Ma Bridge site.