Rail - Railway Tunnels

Tunnel projects of Shinagawa Central Ring Road are very essential to reallocate the traffic jam in Tokyo as well as to establish easier accesses to the suburbs out of Ring Road. Most of tunnels are built of caisson placed underground and need to be waterproofed. Sika acquired one section “Ohi Section” with total spray area of 6000 m2.

The tunnel was part of ’Bahn 2000’ (a major extension and renewal project for much of the Swiss rail network).However, only 10 years after completion, arch cracks occurred at about 40 meters due to excessive swelling of Gypsum Keuper in the surrounding geology, so substantial repair works were urgently required. The forces exerted had actually lifted the tunnel invert by up to 70 mm over a 40 m section. To permanently solve this problem, additional concrete beams were installed as abutments along the lifted section and these were firmly anchored with rock bolts, to transfer any future forces directly into the bedrock of the mountain.

The Dubai Metro is a driverless, fully automated metro network that will already be the largest in the world, at over 70 kilometres, when the second ‘Green Line’ of the four planned lines is fully open in 2011. These first two lines that are nearing completion have elevated sections for 58.7 km and underground sections in tunnels for 12.6 km.