SDS Limited proposed a non-piled solution – dynamic compaction/replacement – which would significantly reduce the construction programme and contribute a significant cost saving of 10% of the overall €50million build cost
It will be the first time this dynamic compaction/replacement technique has been used in Ireland. Instead of piles and a heavy foundation and floor, standard pad foundations and a standard ground bearing slab can be utilised. This technique comprises granular pillars of 1.5m-2.0m on a typical grid of approximately 4.0 x 4.0m. The pillar itself is formed using granular material 0/400 with a fines content <15%, which would be free draining and alleviate water pressure build up. This design will achieve a bearing resistance (SLS) of 150kPa and the budget cost of this ground improvement is approximately €1.2million for a floor area of almost 60,000sqm.