Alongside Arsenal's accelerating Premiership campaign since Christmas, contractors on the club's new stadium have been gathering steam a stone's throw away from the Gunners' 34,500 capacity home at Highbury in north London.
Work on a new, bigger stadium for this year's champions started on site a year ago. But the project had to be mothballed in April 2003 when the deal to finance the stadium fell through, pushing the completion date back from summer 2005 to summer 2006.
Just after Christmas, main contractor Sir Robert McAlpine reactivated the site, amid signs that a firm financing deal was ready to be completed.
New tower cranes started to appear and steelwork for two massive footbridges arrived.
These will cross railway lines around the site boundary, linking the east side of the stadium to Drayton Park, a local road and access point for the underground and suburban rail lines (see box).
A week before the finance deal was sealed foundations subcontractor Stent was back on site blazing the trail for construction of the stadium bowl. NCE understands that Sir Robert McAlpine was so keen to crack on that it agreed to underwrite work after the restart until financing contracts were signed. In the event the guarantees were not needed.
Slipforming subcontractor Byrne Brothers also arrived and began casting the first of eight massive 25.7m high shear cores now taking shape around the edge of the stadium footprint.
These will house stairwells and carry loads from the stands.
For Stent, the challenge has been to keep ahead of the slipformers. It has the task of inserting 1,635 bored CFA piles to support grandstands for the 60,000 capacity stadium. Piles come in three lengths: 20m for the shear cores, and then 18m and 16m for the middle and lower tiers. All are 600mm diameter.
Heaviest pile loadings are 2,000kN under the shear cores which will carry the roof and outer sections of the stands.
Stent is using two CFA rigs and is speeding work by using prefabricated reinforcement cages. These are stored on site in U-frame stillages which can be easily moved around by crane.
It had installed 235 piles last year before the site was mothballed. Starting back on site in February, Stent was tasked with putting in another 970 piles.
All of these will be in place by the end of this week, leaving 430 to be installed in October: The contractor is waiting to get its hands on part of the site currently occupied by a waste transfer station. At the moment it stands where the pitch will be and it overlaps the southern edge of the stadium, preventing construction of the shear cores located here. Stent will return in the autumn to complete its work once the waste transfer station has been demolished.
Piling has gone well since work restarted, although there were some initial hold ups as Stent sought to finish off work left over from last year.
Ground conditions are fairly consistent London clay with the odd obstacle, which has been broken out by demolition contractor Kelpay. Kelpay is also completing demolition of buildings from an industrial estate which occupied a large chunk of the site.
'Sir Robert McAlpine has got us well ahead of the follow-on trades. Our target was eight piles a day per rig, but we have been doing 14, ' says Stent project manager Max Gwynne.