Tips & News - April 2012

HELICAL piles: New foundation design revives c o l l ap s i ng 500 kV t owe r s by Doug Hudspeth Front Line Manager Hydro One Networks Inc. Ontario, Canada

Late in 2008, an aerial patrol discovered three 500kV towers with partially- collapsed foundations on the power line between the Pinard Transformer Station and Porcupine Transformer Stationon theHydroOne system. Itwas a serious problem. The line transmits power from the Otter Rapids, Harmon and Kipling Generating Stations 100 miles down toTimmins.

30,000 km " of high-voltage transmission lines inOntario. Those towers are ‘V’ shaped, supported by a single pedestal foundation and four guy wires. The buried, pedestal foundations are constructed of lattice steel — four legs of angle irons that taper out as they extend down until they are 3 feet wide. From there they extend straight down an additional 5 feet. The angles are supported by diagonal members (flat bars and angle irons). The pedestal sits on top of a network of steel angles and timber mats. No concrete is involved. HydroOneowns almost "

www.hubbellpowersystems.com

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