Volvo High Reach Excavator Brings Down Metrodome
For a construction cost of just $55 million in 1982, the Hubert H. Humphrey Metrodome in Minneapolis certainly earned its place in sports history. The stadium is the only facility to have hosted a Super Bowl (1992), two World Series (1987, 1991), a Major League Baseball All-Star game (1985) and two Division I collegiate basketball Final Four playoffs (1992, 2001).
But earlier this year, it took just four months to bring the Metrodome to the ground and haul away the remains. A new and larger $975 million stadium is being built simultaneously with the demolition of the old one, on the same site. As demolition is completed on one section of the Metrodome, foundation work for the new facility can begin there.
Frattalone Companies, St. Paul, Minn., was chosen to bring down the Metrodome, and the company began actual demolition in minus 20 degree temperatures on January 18. Located in downtown Minneapolis, the Metrodome was a concrete structure with a fiberglass fabric roof that was self-supported by air pressure. Thirty-six steel cables, each 3.5 inches in diameter, anchored the fabric in place from the top. At the top of the roof, a massive concrete ring beam held the cables in place and encircled the entire structure. Inside, precast stadia supported three seating levels for 64,000 people.
The below-grade foundation of the facility was all concrete, explains Chris Niemand, Frattalone’s project manager for the demolition. Cast-in-place walls bore on concrete caissons that went to bedrock.
Frattalone first cleaned the building out, removing materials that could not be recycled or hauled to a landfill. It took about three weeks to remove a loading dock from the facility. While that was happening, crews prepared the ring beam for the removal process. Small explosive charges were used to sever each of the cables from their anchors, and the fabric roof fell to the ground. Similarly, explosives were used to implode the massive ring beam and bring it down. An implosion of the entire structure was considered, but the Minnesota Sports Facilities Authority ruled it out because of the impact it could have on the surrounding community, including a hospital.
For this demolition project, others to follow, and for general excavation work, Frattalone bought a Volvo EC480 high reach excavator and a selection of demolition attachments. “The Volvo high reach has been utilized in multiple different fashions since we started the demolition,” says Niemand. “We brought it in immediately once the building was turned over to us to help prepare for the mass demolition process. We were able to utilize the Volvo high reach itself for reaching up and pulling all the chairs and debris down to the field level. It was a concrete stadium so it would not have been easy to get anything up there to clean off the concrete.”
Tony Frattalone, president of the company that was founded by his father, Frank Frattalone, says he bought the Volvo EC480D for three reasons. First, it is a versatile machine. In a matter of one hour, workers can exchange the high reach demolition boom for a digging boom and stick to prepare the machine for excavation work. “That gave us different options and we could maintain a profitable piece of equipment that doesn’t have any downtime,” Frattalone said.
The second reason is that one manufacturer, Volvo Construction Equipment, builds the entire machine – including the high reach boom – and makes parts for it. “Having a one-stop shop for me was important,” says Frattalone. “The other manufacturers did not allow that, so that was a very strong factor for me in buying the Volvo. Thirdly, the pricing on it was very fair. Compared to competitors’ pricing of their machines, the Volvo was a sound choice for the Frattalone Companies.”
Frattalone Companies was established in 1970 by Frank Frattalone, Tony’s father. Tony manages field operations and the equipment, while Nick, a brother, handles office and business affairs. Some 60 percent of the company’s business comes from grading and excavation work; 25 percent is demolition; 10 percent is sewer and water utility work; and the rest is miscellaneous environmental work. The company also owns Dawnway Landfill in Inver Grove Heights, Minn., which accepts non-hazardous debris from construction, demolition and remodeling projects.
When the seats were removed, Frattalone could move the Volvo high reach excavator around on the playing field to remove the club-level suites in the stadium. “Once again the mobile high reach was positioned inside the building, reaching up and pulling the suites and building materials downward,” Niemand said. “We could have done this in a variety of other ways, but there would have been fall hazards and leading edges to work with. The high reach let us reach up there and pull that material down without putting anyone in harm’s way.”
Once the roof deflated and came down, Frattalone moved into the mass demolition. “So far we’ve been going around the building and removing different structural components built with both precast and cast-in-place concrete,” says Niemand. “The components that we have focused on with the high reach are about 75 feet off the ground. Its main focus has been up on the cast-in-place concrete bent structures that supported the precast stadia and ring beam. We use a Kinshofer multi-processor to cut away the precast stadia that spanned the concrete bents, nipping them down and bringing them down to grade. The precast that we have been working on is mostly about 4 to 5 inches thick. The cast-in-place concrete bents that we have been working on are about 2-foot and 3-foot-thick columns. Some get larger than that, upwards of 2 by 4 feet. So far we have had no issues. Everything has come down just as planned.
“Once the building structure comes down to grade, we’ll move the machine inside and work on the lower level tunnel,” says Niemand. “Once it has been exposed, the high reach can work at ground level to demolish those walls. They’re about 30 feet tall, and the operator can work back from a safe distance to take down the cast-in-place walls to the point that our smaller equipment and excavators and loaders can process and further remove that part of the building.
“It’s a very similar structure all the way around the building, so the process of getting the bents down and removing the precast has been very repetitive,” says Niemand. “Once we move inside and begin work on the lower level tunnels, working from the playing field, that tunnel goes about three-quarters of the way around the building. So that will require a very similar process with the cast-in-place concrete again. Plus, precast floors are intermixed at some of the levels.”
Niemand said the Volvo high reach excavator is not only safer than other demolition methods, it is more precise than a crane and wrecking ball. “You have a lot more control with the high reach tool, versus a wrecking ball,” he said. “The high reach is very precise; the operator can work directly on the components of the structure that he needs to work on.”
Moreover, the Volvo high reach excavator is a faster, more productive way to demolish the Metrodome. “Normally a crane and wrecking ball are very efficient at bringing down a large masonry type structure, but that is not the Metrodome where massive concrete structural members are the order of the day,” Niemand said. “In that environment, the ability of the Volvo high reach to shear off structural members and get them on the ground for further processing far exceeds the crane-and-ball rates of production.”
Tony Frattalone – who came up through the ranks of his company from being an equipment operator – appreciates the fuel economy of his Volvo EC480D high reach excavator, as well as the fuel economy of his other Volvo machines. “Fuel prices have gone up to where they’re nicking that four-dollar mark,” says Frattalone. “Our Volvo equipment is extremely easy on fuel. Their excavators, articulated trucks, and loaders — I have run them all — seem to do a really good job with production and fuel efficiency.”
Frattalone’s other Volvo equipment consists of two A40 articulated trucks, two L110 wheel loaders, two L90 wheel loaders, one L250 wheel loader, and two Volvo excavators – an EC240 and an EC360. “I think the front end loaders that Volvo makes are second to none – right at the top,” says Frattalone. “One of our L90 loaders has 18,000 hours on it, and it’s still working on its first engine. It’s a very impressive tool. The other L90 that we have behind it has around 15,000 hours. That’s in the same boat. The two L110 loaders are newer, and they have been extremely good to us.”
Frattalone says approximately 80 percent of the concrete, steel, and other materials from the Metrodome can be recycled. Some 80,000 tons of processed concrete will be brought to Frattalone facilities and recycled as road base or concrete aggregate. In addition, Niemand says 4,000 tons of recyclable steel will be salvaged and recycled.
Both Frattalone and Niemand emphasize the importance of safety at the Metrodome project. Upwards of 10 full-time safety personnel walk the entire project, including the new construction, to help ensure worker safety. “The safety plan around and for the Volvo high reach is something we put together immediately after taking delivery of the machine,” says Niemand. “We only use two operators for this machine. Those operators have learned the boundaries of where they can work and where they cannot work. And we have set up specific fall zones for where the debris will likely land for working on elevated components of the structure. Plus, nobody is to enter an exclusion zone around the Volvo high reach without getting clearance from the operator to proceed toward the machine. And we utilize a laborer on the ground as extra eyes and ears for the operator, because the operator is focused up above where he is working.”
Tony Frattalone says he and company personnel have a great working relationship with Nuss Truck and Equipment, the local dealer for Volvo Construction Equipment. “They have made great strides of progress since their inception,” says Frattalone. They’re very good at supplying us with parts that are needed and support out in the field, which makes it a lot easier to purchase Volvo equipment.”
At the Metrodome, Frattalone’s contract is with Ames Construction, Burnsville, Minn., which is a subcontractor to Mortenson Construction, the project’s prime contractor. Ames has a $36 million contract with Mortenson for the excavation and demolition involved at the project. The implosion contractor, a subcontractor to Frattalone, is Idaho-based Advanced Explosives Demolition.