Tips & News - April 2012

TIPS NEWS &

approaching Winterwas fast "

After the helicopter patrol found the problem, a ground-based patrol went out to assess the situation. The site is marshy and during the winter the frost heaves the ground up and down. This movement tore some of the diagonals off of the grillage footing. Without the support of the diagonal members, the main foundation legs bent and the foundation began to give way. Three structures had partially collapsed, but they hadn’t completely tipped. A quick repair was required to prevent a complete failure of the foundations, but access to the structures with large equipment/crane was not possible without extensive road construction. Instead, a temporary repair was made. Our travelling line crew out of Sudbury installed blocking to carry the weight of the structures, until permanent repairs could be made. Deciding on a Solution Back in the 1980’s, Hydro One had used some CHANCE ® piles under similar conditions, but no one who worked on that project was still around and the work was not well documented. But, after reviewing the situation, it was decided that horizontal beams welded onto helical piles would be the best option. With this approach, we would not need to excavate or remove and replace the existing foundations. Therefore, we would not need to bring in big earthmoving equipment. Winter was fast approaching and it was too late to do anything else in 2008.

" and itwas too late todoanything in2008.

Members that were broken off by ice

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