For the faculty and students of Arkansas State University in Jonesboro, the demolition of the Seminole Twin Towers is the end of an era.
From 1967 to 2006, the Twin Towers housed university students. It was a place to study, to sleep and to call home for the academic year.
But those 40 years were brought to the ground by explosives May 25 in just 15 seconds.
And just another month later, the last truckload of structural debris was removed from the site.
To Trey Chandler, project superintendent of Chandler Demolition in Memphis, Tenn., the job was just a “different building, different address.”
The site was one of the easier ones, Chandler said. There were only three buildings in close proximity to the Twin Towers, a nine-story building with a concrete frame, spread footings and a concrete block back-up with brick veneer covering 175,204 sq. ft.
“This building was pretty much sitting by itself,” he said.
To ensure the neighboring structures weren’t damaged by the implosion, the windows and doors were covered by a protective black fabric. The building went down early in the morning at the time of year with the fewest number of people on campus.
While the actual implosion draws the most attention, the work started weeks beforehand.
Chandler crews first arrived April 1 to completely strip out the first, third and sixth floors and parts of the eighth floor. These were the floors in which Controlled Demolition Inc. (CDI) of Phoenix, Md., would place 200 lbs. of nitroglycerine-based explosives in 1,100 borehole locations at structural supports. On these floors, Chandler said his crews left nothing but the concrete walls and columns.
During the preparation process, the Chandler crew consisted of 15 to 20 laborers a day. To strip the wood and sheetrock debris, the workers used three Cat 262 skid steers and a Cat 305 mini-excavator.
The CDI crew joined the fray approximately three weeks before the implosion date. They used that time to drill bore holes for the explosives and make sure the building was going to come down as planned.
Chandler Demolition returned to the scene May 26, the day after the demolition to start the clearing out process.
After the crowd-drawing show, Chandler said his crews “still had half a job left to get this thing gone.” He added that the implosion went smoothly and the floors “were stacked up like a pancake” in an 18-ft.-tall (5.5 m) pile.
The first two days were spent separating the material, as the metal in the building was to be recycled.
The concrete was hauled to a local landfill.
Chandler didn’t know how much material was created by the implosion, but a university fact sheet estimates that 360 tons (326 t) of debris is usually felled per pound of explosives. That would work out to 72,000 tons (65,317 t).
During this phase of the work, Chandler called in some larger pieces of equipment: two Cat 345 excavators (one with a hydraulic thumb), a Cat 322 excavator, a rented Komatsu PC300 excavator, two Cat 262 skid steers and a Cat 325 with a hydraulic breaker.
The task of this fleet was to separate and downsize the material so it fit into the trucks to be hauled away. Chandler used three trucks from Mack and Freightliner, two with 28-yd. trailers and one with a 30-yd. dumpster roll-off, to haul away concrete. Two other trucks were dedicated to hauling scrap metal.
Including truck drivers, this phase called upon 10 to 12 crew members.
Even though the Chandler crew has hit ground level, its work isn’t over yet. Chandler said they now have to dig out the building slab and sidewalks, which should take approximately three weeks. Then the crew will fill in the building’s basement with dirt to bring it up to grade.
The site will remain green space in the near future, but may be the future site of an academic building contingent on funding.
Chandler doesn’t expect any problems meeting the Aug. 1 deadline since the process up until now has been a smooth one.
“The people at the school have been really easy to deal with,” he said. “The building is all in one fenced-in gate, so there was nothing major that could ever go wrong.”
The building that will be just a memory in a matter of weeks was constructed over six months in 1966 and 1967 by Harmon Construction of Oklahoma City, Okla., for $2.96 million. (The demolition cost just more that $1 million.)
Chandler Demolition Company was established in 1946 as Chandler Wrecking Company.
It changed its name in 1989 “in response to changing times and industry trends,” according to the company’s Web site (www.chandlerdemolition.com).
Since 1994, the company’s work has included asbestos abatement.
The family business is now in the hands of the fourth generation of Chandlers. CEG
Today's top stories