K & C POWER HOUSE REPAIR

59 CLEAR LAKE ROAD NORTH, KAPUSKASING, ONTARIO, P5N 2X7

TEL: (705) 337-5211

FAX: (705) 335-6364

TIE DOWN ANCHORS

After doing engineering studies of some of the older generation stations, it was determined that the safety factor was not great enough to prevent over turning or sliding under extreme circumstances. One example would be a sudden thaw, creating high water, along with a massive build-up of ice in the forebay. It was found that the way these dams were anchored to bedrock plus the weight of the structure itself did not leave the desired safety factor. This left several options; one - add weight by adding more concrete, this would have been very costly. Working closely with the owners and Geocon-Engineering, it was decided to have K & C POWER HOUSE REPAIR install double corrosion protection anchors. These anchors are designed to secure the dam to existing bedrock. To install these anchors, 4 3/4" holes were drilled through the dam and 25 ft. into the existing bedrock. Due to limited working area, conventional drilling would not work. K & C POWER HOUSE REPAIR used a down-the-hole hammer mounted on a standard core drilling rig. When steel was encountered, the hammer was removed and diamond bits were used to cut through the steel. Using this method, K & C POWER HOUSE REPAIR was able to drill about 70 ft./day. After all holes were drilled, washed out, and pressure tested, the anchors were installed. To do this, K & C POWER HOUSE REPAIR built a 40 ft. tower mounted on a barge to lift the anchors prior to lowering them down the hole. When the anchors were in place, they were grouted to the top of the existing bedrock. After 7 days, the anchors were loaded to predetermined capacities, then grouted to the top of the existing concrete. All anchors were recessed 12 inches into existing concrete to preserve the same neat lines. These anchors can be chipped out and retested at any date in the future.