Old Tower at Memphis International Being Dismantled
Structural demolition of the old tower (186 feet tall) at Memphis International Airport, which was constructed in 1977, began earlier this month with removal of the cab, a structure that weighs between 24,000 and 26,000 pounds.
How can something so tall and so heavy be safely and efficiently dismantled? The secret begins with removal of the central concrete support shaft and the use of a diamond wire saw from inside the shaft. Five-foot sections are cut and then lowered to the ground. These saws have been used to cut reinforced concrete during demolition work for several decades. The saw features a steel cable threaded through steel beads to which diamonds have been bonded. This method creates little dust, noise, or vibration, and can cut through almost any material because of the hardness of the diamond abrasive.
A series of holes has been bored through three sides of the structure to thread cable for lifting each section and then lowering it to the ground in a stable fashion. The concrete shaft will be removed in this way down to about 50 feet in elevation. The remainder of the structure then will be excavated with a jackhammer. All the concrete, including the basement, will be removed and the hole will be filled with sand.
The removal project should be completed by mid-January.
Photo credit: John Hilbert, Flintco, LLC