Balfour Beatty Ground Engineering (BBGE) is carrying out its first use of pencol rigid inclusions in Scotland to improve the ground conditions ahead of construction of a new warehouse.
The technique is being used on the site of a new distillery warehouse in London Road, Glasgow to support raft foundations for main contractor Muir Construction.
BBGE originally assessed the suitability of the soils for ground improvement using vibro stone columns but these were ruled out due to the soft organic, silty nature of the soils. The traditional alternative in these circumstances would have been to use piles with a reinforced slab but BBGE proposed using the pencol as an more financially viable solution.
As the technique is new to the Scottish market, BBGE hosted a demonstration of the pencol method at the Glasgow site for more than 30 customers, engineers and contractors.
“I believe Pencol has a role to play in the ground engineering market,” said BBGE ground improvement director Vincent O’Hara. “Rigid inclusions sit somewhere between stone columns and a piled solution. It allows us to provide an alternative to piling and we believe there are many benefits to its use.”
O’Hara believes that pencol offers an effective ground improvement technique to provide enhanced bearing capacity and settlement control in very weak or organic soils. It works by injecting concrete through an auger to form closely spaced grouted columns or rigid inclusions, so the ground between the columns carries a proportion of the load.