HS2 cross passage construction will be the subject of the British Tunnelling Society’s December lecture.

Speakers from Skanska Costain Strabag (SCS), the joint venture responsible for Main Works Lots S1 and S2 on the high-speed rail project, will discuss an integrated method for safely constructing the cross passages in challenging geological conditions between two TBM-driven running tunnels.

Of the 20 cross passages to be constructed, artificial ground freezing (AGF) is being used on 14, and dewatering and depressurisation methods on three.

Traditionally, AGF has been used primarily for rescue operations and its application in the UK has been limited because of cost and time constraints. Its use on HS2 is the most extensive AGF application undertaken on a single project in the UK.

Strabag UK tunnel agent Ala Hammad, Strabag UK tunnel engineering manager Phil Allvey, and SCS JV lead tunnel engineering manager Dave Terry will also discuss lessons learned from this approach, providing insights for future projects.

The lecture will be held at the Institution of Civil Engineers, 1 Great George St, London SW1P 3AA on December 12 and will also be streamed live.