From a high rise building in France to a massive fuel bunker in Scotland, performing demolition work in Europe poses some interesting challenges. Attendees at the 2012 C&D Recycling Forum had the opportunity to hear how demolition contractors have approached these projects using unconventional methods.
Stefano Panseri, managing director, Despe Srl, Italy, showed how a new method for deconstruction of skyscrapers called the TopDownWay successfully brought down a skyscraper in Lyon, France.
Panseri described how the TopDownWay seals the structure to be demolished, keeping the stripped out material and demolition debris inside. The system is installed on the top three stories of the skyscraper and moves down, eventually taking down the entire structure.
“With this system, the machine works on three stories of the skyscraper at a time, performing a number of different operations simultaneously: the destruction of the facades and their coverings, the removal of the windows, the demolition of and the contaminant of the rubble,” Panseri described. “As the work proceeds, the platform descends to the next level by means of controlled-mode operations.”
Despe submitted a proposal to demolish the Tour Uap building in Lyon, France. The building, while small by U.S. standards, was extremely large by European standards including two-below-ground stories, a three-story parking garage, 17 office building stories and a technical story, Panseri said.
“If we were to be awarded the tender contract, we had to come up with an idea to demolish the building quicker whilst meeting all the contractor’s requirements,” Panseri said. The requirements included no dust, no noise, no vibration and no disturbance in the district. TopDownWay was the winning proposal. Panseri calls the method “a complete rethink of the philosophy of demolition.”
Panseri said the demolition occurred at a rate of two stories per week and achieved a recycling rate of 95 percent. “As witnessed by the operators and city council representatives, the Uap tower disappeared quietly in less than four months.”
David Sinclair of Safedem Limited, based in Dundee, U.K. is in the middle of one of the largest demolition jobs of his career: a 9.5-acre bunker in Rosyth, Scotland with 8-meter-thick-walls and a 7.5-meter-thick roof all made up of more than 1 million metric tons of reinforced concrete and 2,200 kilometers of reinforcing bar.
“We’ve done a lot of demolition jobs in the past,” said Sinclair, "but this was the mother of them all.”
The bunker was built in two phases. The first phase was completed in 1918. Then in the 1930s, another bunker was built on the outside of the original bunker to reinforce it so it would withstand an attack. The bunker was used to store fuel for ships
When demolition first began, Sinclair recalls, “We weren’t getting very far or going anywhere fast.”
Crews learned that they were able to make more headway if they drilled horizontally rather than vertically. They also used explosives. Using non-explosive props, Sinclair demonstrated to attendees how he created sausage-like explosives that have “nibbled away” at the structure. The explosive devices were created using dynamite and an amoblast, which is a combination of ammonium nitrate and fuel oil. He said crews have conducted about 430 explosions like that.
Safedem is in its fifth year of demolition at the site and has approximately two years to go before the demolition will be completed.
“Our saving grace has been the price of scrap,” Sinclair said.
The C&D Recycling Forum was Sept. 23-25 at the Hilton Long Beach & Executive Meeting Center, Long Beach, Calif.