London, UK

The Crossrail concept goes all the way back to the 1880s. In 1944, it was considered as part of the Greater London Plan, which was developed to reduce population density in London. However, it was put on hold due to World War II until being finally discussed by parliament in the 1980s.

In 1985, a waterfront redevelopment called the Canary Wharf Project was announced, but unable to raise the enormous construction cost of 14.8 billion pounds (about 2.5 trillion yen), the project was again put on hold for 30 years until the Crossrail Act 2008.

Then Prime Minister Gordon Brown held high hopes for this project, but constructing the foundations for the station building, at the bottom of a canal and under 10 meters of water, was very difficult. The GIKEN Group was able to achieve what conventional construction methods were determined unable to do. At the groundbreaking ceremony, which was broadcast on television across the UK, Mayor of London Boris Johnson and Transport Minister Lord Adonis pressed the start button on the SILENT PILER™ for tubular piles to install the first pile.

In addition to being London’s business district, the construction site comprised hard ground with a maximum N-equivalent value of 750. The Hard Ground Press-in Method is a vibration- and noise-free construction method able to work in hard ground without requiring temporary work platforms, and it is able to work in canals without polluting the water with drilling sediment. The superiority of this method over conventional continuous wall concrete construction was recognised in the construction method screening process, and the method was specially chosen as the designated construction method. Time for construction was also dramatically reduced with two machines using this one-step approach (combining temporary work with main work).

In addition, high-quality construction materials (cast-in-place concrete piles and composite structural piles) were manufactured in a factory for the continuous press-in work, achieving stable, high-strength wall construction.