Challenges
We were working from platforms attached to the dam face and on the narrow crest of the dam with precipitous drops on both sides, where every move of equipment, tools and technicians had to be calculated. In addition, meeting the condensed schedule required devising a cutting pattern which allowed the saws to run simultaneous to prep the 20,000-60,000 lb. cut blocks for removal.
In order to initiate cutting and secure the horizontal saw frames, we core drilled 4” wire access holes through the dam’s 28’ width. Using these core holes as access for traditional wire saws, we were able to cut vertical slots into which we placed our patented rail saw frames which would do the horizontal cutting. Because our rail saws are custom designed and fabricated for the job, they could be used on the ogee crest for precision cutting both vertically and horizontally. Our team stacked two horizontal saws and two vertical saws into position on the ogee crest and operated all saws simultaneously, significantly accelerating cut times. We arranged the cutting patterning in a way that gave Kiewit access to drill, install and grout the rods needed to lift blocks at the same time we were cutting, and the cutting plan allowed for efficiently positioning cranes, which also enhanced the schedule.
Solutions
Outcome
Our patented rail saw design, its reliability and efficiency, and the expertise of Bluegrass technicians at planning, setting and operating the saws, resulted in Bluegrass precision cutting over 20,000 SF of concrete into blocks at an average rate of 20 SF/hr with no safety incidents.