Case Study

HS2 Rail Road Buckinghamshire

Following working on the South Portal of the Chiltern Tunnels we moved on to the central section haul road

Lime and cement stabilisation
two and a half years and counting (at December 2021)


HS2 Central Section Haul Road

We are involved in constructing the 69 mile long haul road that is required to facilitate the main railway construction works on two of the central sections, C2 and C3, of the first phase of HS2. This phase is 140 miles long in total stretching from London to Birmingham and is the main civils works element is divided contractually into seven sections.

The 7.5m wide haul road will be used by construction traffic and feature differing solutions dependent on the subgrade conditions. Lime or lime/cement binders are being used to achieve the 15% or 30% CBR requirements. Alternative binders marketed under proprietary names were also tested but it was found that the EN Standard lime or lime/cement binders we always use achieved similar or better results. And with considerable cost benefit. Finishes to the single or two layer depth will include roller compacted concrete, MoT Type 1 aggregate and, potentially, blacktop.

As we have had regular and early involvement in the project we have continuously assessed the need to invest in increasing the size of our fleet of plant and equipment. This has been carefully managed to achieve the HS2 requirement of seven teams at peak and six on average whilst having no detrimental impact on our regular customers and sectors. The fleet is now around twice the size it was only a few years ago.

This is not our first experience of HS2 as we are also involved in central area contract C1. We worked at the south tunnel portal works (see image above) for the twin bore 10 mile long Chilterns Tunnel and the embankment works adjacent to the portals. In addition areas for the tunnel arising temporary storage, the project compound and car parks have been completed during the two and a half years we have worked on the project. And we are now treating the tunnel arisings following commencement of tunnelling operations.