Looking back we see the lessons shared from the Crossrail project – now the operational Elizabeth Line – continue to be available, thanks to Transport for London (TfL) choosing to keep the Crossrail Legacy initiative active and online, its educational materials free to access. We have a run-down on what the Legacy Library holds and, in recalling the project, offer a sampling of its many scenes during major tunnel works – from SCL and caverns to visualisation and TBMs – under the heart of the capital.

A look back is also provided on the staggering number of large tunnel projects over the last three decades in China, and with more to come. The information is shared with readers in advance of the World Tunnel Congress 2024 (WTC 2024), to be held in Shenzhen, China, over 19-25 April 2024 – with a training course, conference, and multiple technical site visits to large tunnel works in the city and vicinity, including Hong Kong. The major article for T&T includes notes on those site visit plus other large tunnels being farther away, across the country.

Ahead also – and for the entire global industry – is the possibility offered by digital systems, and this issue of T&T carries an article on the convergence of BIM and Digital Twins. But data go into and out from those digital pipelines. Seasoned engineering oversight is therefore vital, and also in helping to conceive new practical possibilities with such systems. In that regard, another article discusses the challenge of access to data, while another throws a project spotlight on smart and speedy automation of data processing for ground settlement analysis.

For our technical focus on waterproofing, insights from a BTSYM workshop are shared, and also a perspective on segment accessories.

Last word, in looking back – T&T’s Annual Index is available for 2023.