Read the summary of the text and correct some technical mistakes.

Gotthard base tunnel in Alps is one of the largest civil engineering projects of recent years. It passes through difficult geology and at great depths beneath the Alps. Simultaneous work from three work sites will reduce construction time with the first train due to run through in 2011. The hardest part of the project – creating running tunnel through the most difficult geology. the rock is a type of sugar-crystal dolomite varying from water bearing rock to almost liquid. To chose the best technologies many exploratory bores were made.

The direct rail-based excavation was possible and to minimize the environmental impact it was decided to transport 50% of materials for the tunnel by rail. Special railway lines were constructed including signaling, power supplies and extra passing loops. The most of the materials for the tunnel transported by rail will be metal. Much of the tunnel spoil will be brought out by rail too.

A funicular railway has been installed to transport workers up and down the hillside.

Workfaces for the running tunnels will include:

- a cavern at the bottom of the Sedrun shaft to provide space for moving equipment,

- creating passageways and initial tunnel sections through the easy geology,

- the twin tunnels and crosspassages which should connect with a drive from the Amsteg access,

- a second face at Sedrun boring the tunnels south,

- fitting out on the outer ends of the tunnel.

Many technical challenges lie ahead, but this huge project promises to transform the heart of Europe’s rail network.

Make a list of technical aspects that you should consider when designing a deep hard rock tunnel.

These statements about tunnels and viaduct in Hong Kong are all false. Read the text below and correct them.

1) Kwai Tsing tunnels pass in easy geology.

2) A mixed-face earth pressure balance TBM has been used for the second time in Hong Kong to excavate a key section.

3) With an 8∙ 7 m diameter with a cutting head, the TBM is capable of digging only hard rock.

4) Tai Lam tunnel was excavated using shield-driven tunneling method.

5) The elevated alignment through the north-west New Territories avoids cutting across roads and disrupting the flow of water down drainage channels in flood-prone areas but doesn’t provide minimizing land take.

6) Viaduct noise preventing measures include a 1 m high parapet, train skirts and fixed slab track mounted on wood pads and resilient baseplates.