BAUER Foundations Canada was awarded the construction of 9 piles, with 2000mm diameter permanent liners and a rock-socket of 1850 mm diameter, 5 to 8m long, for four bridges along the highway 1 in New Brunswick: over Letang, Digdeguash, Lepreau and Magaguadavic rivers. The length of the piles varies from 10m to 66m and a 1m embedment of the liners is required in the bedrock.
The length of the piles varies from 10m to 66m and a 1m embedment of the liners is required in the bedrock. Because of the various locations of the rivers along the project, different types of bedrock were encountered. If at Letang River and Lepreau River the bedrock consists of metasilstone rock, a highly to moderate weathered rock and very weak to very strong strength, at Digdeguash River a very strong Basalt,slightly weathered, was encountered. At Magaguadavic River, a medium to very strong rock was encountered.
BFCA had to mobilize and demobilize the BG40 rig at each river location as soon as the client prepared the working platform, even once on a trestle because of the big change of water depth caused by the tides, leading the original barge option to be obsolete. The challenge was getting bigger on Magaguadavic River where the bedrock is very deep, from 54 to 57m from platform level.
BFCA decided to mobilize an oscillator from Germany to install the permanent casings in sound bedrock and a cable grab to excavate the soil until bed rock is reached. To drill the rock socket, our powerful BG40 with a 72m Kelly bar was used to reach the maximum required depth of 66m.
All work was completed at the full satisfaction of the client and on schedule.