World’s longest cross-sea bridge installed

Chinese engineers have installed a 6,000-ton key structure of the world’s longest cross-sea bridge linking Hong Kong, Zhuhai and Macao.

Lin Ming, chief engineer of the island and tunnel section of the bridge, said the wedge, 12-metre-long and weighing over 25 Airbus A380 jets, was lowered to connect the immersed tubes of the underground tunnel of the bridge.

The 55-kilometre bridge connects Zhuhai in Guangdong Province with Hong Kong and Macao.

It includes a 22.9-kilometre bridge and 6.7-kilometre underground tunnel.

Before the wedge was installed on Tuesday, 33 immersed tubes, each 180 metres long and weighing 80,000 tons had been installed.

According to Chen Yue, director of the engineers’ office of the bridge’s island and tunnel section, there is only one wedge for a tunnel, and they cannot afford to fail in its installation.

“It took two years to prepare for today, the installation procedure took about six hours.

“The margin of error for the wedge is 1.5 centimetres. We have to measure precisely the influence of wind, current and buoyancy force.

“It is like putting a needle through a hole – a truly unprecedented event in the history of transportation,’’ Lin said.

A gigantic crane, which was transformed from a tanker, was used to hoist the wedge, lowering it to the desired destination between the underwater tubes.

“The wedge will be welded and finished by June,’’ Lin said.

Zhu Yongling, director of the bridge management bureau added that by the end of the year, the bridge would be open to traffic.

Report says construction began in December, 2009 at Zhuhai. The Y-shaped Bridge starts from Lantau Island in Hong Kong with branches to Zhuhai and Macao.

Zhu said the bridge would cut travel time from Hong Kong to both Zhuhai and Macao from three hours on the road to a 30-minute drive.