Trelleborg supplies sealing systems to Hong Kong immersed tunnel project

Hong Kong, China – Trelleborg AB’s marine and infrastructure operation has supplied tunnel sealing systems for the immersed tunnel section of Hong Kong’s new Sha Tin to Central Link project.

Under construction by Hong Kong’s Mass Transit Railway (MTR) Corp., the new line will enable easier travel between Kowloon and Hong Kong Island.

The line, which partly opened in February, includes a 1.7-kilometre immersed tunnel section in Hong Kong’s Victoria Harbor, for which Trelleborg supplied to two sealing system, the Swedish supplier announced 3 June. 

Trelleborg said it provided its Gina gasket, which is able to withstand extreme pressure to prevent water ingress, as well as its Omega seal, which serves as a secondary safety seal and can endure severe ground movements.

Commenting on the project, John McLeod project director at contractor company Penta-Ocean China State Joint Venture (PCJV) said that Trelleborg's sealing systems were easy-to-install when connecting 1,660 metres of the tunnel’s concrete panels. 

Gina gaskets, he said, are made of a softer rubber compared to other sealing systems available on the market, allowing them to be closed more easily upon initial compression. 

“This meant that our installers could deploy a lighter jacking force to seal the deeper joints and reduce the time it took to close the seals, which also reduced costs,” he added.

According to Trelleborg, the combination of the two sealing systems enables the transfer of hydrostatic loads and movements between the tunnel ends, caused by soil settlement, creep of concrete, temperature effects and earthquakes.
 
Trelleborg also supplied two additional sealing systems to the temporary works to facilitate the construction of the tunnel’s closure joint. 

The additional seals included a dome seal and a side panel seal, which are primarily designed to prevent water ingress.

The tunnel is the sixth immersed tube tunnel in Hong Kong and the first such project for 20 years.
 
This latest project follows Trelleborg’s participation in other major Chinese construction programmes, including the Hong Kong-Zhuhai-Macao Bridge and the ShenZhong Link – the world’s widest immersed tunnel.
 
The cross-harbour section of the Sha Tin to Central Link is expected to open in 2022, and will run from Hung Hom Station in Kowloon, to Admiralty Station on Hong Kong Island.