Placing Booms Star in Hollywood Condo Construction
With a high-rise resume of more than 56 buildings, Florida Concrete Unlimited (FCU), Miami, FL, has developed a proven method to pump, place and finish tall structures. Separate placing booms play a big part in the efficient distribution of concrete over large decks pumped 60 stories high. One of 13 current FCU placing boom projects is the Hyde Resort and Residences in Hollywood, Florida, where separate placing booms are located on two parts of the project and flown between four different mast locations.
“The separate placing boom is standard equipment on high rise construction in Florida,” explains Danny Eichloff, FCU placing boom manager. The company is finishing concrete work on the 42nd story of the Hyde Resort which will contain 407 condo units with ocean views. As would be expected along one of the world’s most beautiful beaches, space is at a premium on the job site. The Hyde Resort & Residences is being built next to an occupied building to the north, a fire station to the south, the A1A highway to the west and the beach on the east side. “We’re on an extremely tight site where we only have 10 feet to the property line on one side, and we’re right up against the property line on the other side,” Eichloff says.
Building within these constraints has been extremely challenging and the concrete work has had to be scheduled precisely to ensure there are no delays. The reliability of the Schwing placing booms and concrete pump is essential to keeping the job on schedule. The project employs two separate placing booms and four 39-foot masts that are secured in floor frames placed on the decks. The typical floors of the high-rise structure are approximately 14,000 square feet requiring two mast locations to reach all areas with a Schwing separate placing boom with 90-feet of horizontal reach. The adjacent parking structure is also being poured with a Schwing separate placing boom with 80-feet of horizontal reach flying by tower crane between two masts.
Supplying concrete to all of the mast locations is a Schwing SP 2000 stationary concrete pump. While FCU has larger Schwing pumps in their fleet, the SP 2000 was sized correctly for the job with its compact dimensions and 118 cubic yard per hour capacity. Eichloff says, “The SP 2000 was determined to be the right pump for the job and it worked remarkably well meeting our fifty to sixty yard per hour goal all the way to the top. We would normally see about 210 bar and never exceeded 220 bar even at the forty-second floor.” The pump uses a fuel-efficient 175 horsepower diesel to power the hydraulic pumps of the twin cylinder all-hydraulic concrete pump that can be switched from high pressure to high volume. The pump placed concrete more than 650-feet through any of four pipelines routed to the mast locations.
Typical pour schedules included one deck per day and verticals the next day. “We would pour half-the deck, fly the boom to the other mast and pour the other half,” explains Eichloff. “Our ready-mix supplier, Supermix, has been excellent with just-in-time delivery of materials,“ he says “Because space is tight, we are only able to have a few trucks staged at one time but we have managed to unload and washout a mixer in about 11 minutes.
The company relied on the tower crane to fly the boom back and forth to the other masts. FCU crews could quickly detach the boom, and remount it in less than an hour. “Because the shear walls are massive on this building, occasionally we would get a start on them by flying the boom back to the poured side to start the verticals.” The 28-inch masts are secured in the floor frames with wedge pins which allows crews to quickly raise the mast between pours.
With as many separate placing boom projects that FCU has successfully completed, each one is different. “We had some non-typical floors where spacing was 18-feet on the pool deck and 20-feet on the next floor,” says Eichloff. The distance between floors did not allow the mast and placing boom to be properly secured. The company reverted back to their Schwing S 61 SX truck-mounted pump with placing boom and used its 197-foot reach combined with three-inch system connected to the end of the boom to pour the two decks. The general contractor specified three-inch line to avoid disruption of the post tensioning.
The nine-level parking structure is enclosed in the building but also juts out from one side of the structure. The company utilizes two 24-inch masts and a Schwing separate placing boom to complete the portion outside the building’s footprint. The masts were installed at the third level after the company’s boom pumps completed the first two parking levels. The SP 2000 stationary pump feeds two lines connected to the masts, and crews are pouring decks and walls at the rate of 300 yards per day.
A factor contributing to the speed of construction is the decision by the General Contractor, John Moriarty & Associates Florida, to forego its typical method of building with a slab-mounted table system and instead used a column-hung table system. “It allows us to progress with the interior build-out a lot faster,” according to Senior Project Manager Jazer Challenger. Unlike traditional horizontal forming systems, the column-hung system’s equipment eliminates the need for re-shoring, which can significantly delay a project’s construction cycle by closing off floors to trades or storage due to load considerations. With the column-hung system, builders and subcontractors — including mechanical, electrical and plumbing workers — have almost immediate access to lower areas of the building while concrete slabs are being poured and forms are stripped on the floors above.
Building within the time and space constraints of the job has been extremely challenging, and the concrete work has had to be scheduled precisely to ensure there are no delays. “Choosing the right equipment is critical,” according to Eichloff, “We have a formula to build high rises on the beach with reliable equipment sized right for the job, Our high rise resume is proof that it works.”