In the spring of 2012, Bermingham was contacted by one of Quebec’s largest general contractors, Pomerleau Inc, to partner with them on the construction of the largest deep water port of its kind in North America. Pomerleau brought Bermingham’s marine rock socketing expertise and ability to quickly design and build custom equipment in on a joint venture basis.
This multi-users dock was to be constructed in the Gulf of St Lawrence in the town of Sept-Iles, Quebec. This dock will have the ability to service two Chinamax ships simultaneously. These ships hold 7 times the volume of a traditional large ocean freighter. The project was awarded in the fall of 2012 and had an almost immediate start-up.
The piles supporting the massive dock were up to six feet in diameter, 195 feet long, and weighed 65 tons. These huge piles were installed and driven to bedrock in one piece and were both vertical and battered.
The rock borings indicated soft rock of 85 MPa. As Bermingham did not have large diameter underreaming bits, they ordered them from a UK supplier. Unfortunately, the bits did not perform as the actual rock strength was 185 MPa - near the upper limit of rotary drilling. Bermingham in house engineering and fabrication came to the rescue - quickly designing and building new bits that could take the downforce (crowd) required to cut this very hard rock.
The drilling was done with our BHD-80 Reverse Circulation Drilling system on a flying lead capable of applying the high crowd loading required.
The work was executed through two challenging winter seasons under significant tidal conditions. Bermingham built bubble systems and utilized underwater sound monitoring to enable construction during the regulated whale mating season.
Bermingham’s rapid response to the changed rock conditions and engineered workaround of the ‘whale window’ enabled the rock socketed piling to be finished just on time.