Holes were 1 3/8″ diameter x 54″ deep
Not really, if you know how to do it, and you have the right equipment. But how do you tear out a 20’ x 20’ x 5’ concrete footing without the use of a conventional wrecking ball or hydraulic hoe ram? This was the question facing Flintco, Inc., a contractor who was building the new Oklahoma State University Interdisciplinary Science and Research Building. The footing was poured to accommodate the use of an overhead crane used in the construction of the new building. After the construction was complete, and the overhead crane was no longer needed, the footing needed to be removed. But due to buried utilities and seismic equipment in use, normal demolition methods were not allowed. Flintco contacted John Jackson with Wittwer Construction Company in Stillwater, OK. Jackson worked with E-Z Drill to fabricate a “special” vertical E-Z Drill system that was modified to drill up to 54” deep. Wittwer drilled about 500 vertical holes, 1 3/8” in diameter, through the footing. A product called “cracker” was poured into the holes. The material would then expand and bust the concrete into smaller pieces for easier removing.
The E-Z Drill vertical drill system took approximately 2 1/2″ minutes to drill one hole. All of the drilling and removal of the concrete was completed in about 4 days.