M27 Motorway - So Many Junctions!
Reworking and installing the drainage, lighting and communications facilities around a fully operational motorway when it is being widened creates almost as much cost and effort as the simple preparation of the new surface.
The brief was simple – carry all required services across the new motorway with zero traffic interference (i.e. 3 lane traffic flow must be maintained!).
This four month project meant working from the central reservation and out to both sides, augering a steel 508mmØ /610mmØ casings out to each hard shoulder.
Adopting our single phase guided system, alongside BM400 & BPU 800 TBMS, we achieved gravity drainage lines, levels & tolerances without any exit shafts or attendances
A blind finish allowed Costain to install product pipe & finish off when needed.
Once the motorway was fully reinstated and working with tolerances of less than 20mm we had to do a “golden shot”, hitting a 110.5 mm target in manhole, at a depth of 1.6m within the completed central reservation, across a 26m length (both ways) – and we hit it first time!
Extreme weather conditions and nightwork made this one of our more difficult jobs.
“Chiltern Thrust Bore just run themselves – they’re a breeze compared to so many sub contractors I have to work with.” Amy Wilford, Costains.