HS2: Construction Begins on First Giant Pier for UK’s Longest Rail Bridge

Work on the first of 56 giant concrete piers that will support the Colne Valley Viaduct – the UK’s longest railway bridge once built – has begun.

The viaduct will cross a number of lakes outside of London and measure 3.4km in length.

The Colne Valley Viaduct under constructionThe Colne Valley Viaduct under construction

© HS2 Ltd

The first pier was cast by HS2 main works contractor Align JV, which comprises Bouygues Travaux Publics, Sir Robert McAlpine and VolkerFitzpatrick, and working in partnership with Kilnbridge.

This concrete pier weighs around 370 tons. Measuring 6m in height, it was cast on site by engineers using a specially-designed formwork to create the right shape. Four days after casting this formwork was removed.

Every pier is designed to support the full weight of the deck above and will stand on concrete piles going up to 55m into the ground. This foundation work started earlier in 2021.

The construction of the first four jetties across the lakes that allow equipment to be moved into position has also been completed. Where the viaduct crosses the lake, the piles will be bored directly into the lakebed. A cofferdam will be used to hold back the water while the pier is being constructed.

source= https://railway-news.com/hs2-construction-begins-on-first-giant-pier-for-uks-longest-rail-bridge/