“Re-writing the Book on Placing Booms”
“Re-writing the Book on Placing Booms”Skyline at MacArthur Place pushes the envelope with outside tie-in technology
STURTEVANT, WI (February 1, 2008) – In the wave of high-rise development in Orange County (the O.C.), California, the sky is the limit. This is especially true for JLS Concrete Pumping (JLS) and Putzmeister America, Inc. at the Skyline at MacArthur Place (Skyline) high-rise project where the two companies continue to set benchmarks with their placing system outside tie-in climbing configuration and pin tower technology.
Skyline will comprise of two 25-story buildings, the North and South Towers, which will soar 300 feet high when complete in mid 2008, according to Cory Alder, president of The Nexus Companies, the developer and general contractor for Skyline. The two towers will include 349 ultra chic, spacious condominium homes including luxury penthouses on the top levels; homes boasting extraordinary views of the O.C. skyline and spacious one to two bedroom floor plans ranging from 1,018 to 2,800 square feet.
Pushing it to the limit
Since arriving on-site in fall 2006, Oak-View, California-based JLS, the concrete pump subcontractor on the project, has been able to push the envelope with their Putzmeister pin tower and outside tie-in placing system not just one, two or three times, but four.
“It really feels likes we’re re-writing the book on placing boom technologies with this project,” notes Dan Navarro of JLS. “It’s revitalizing to see how far we can go with our equipment and how far it will take us.”
Putzmeister equipment on this project includes two foundation-anchored, freestanding pin towers each attached to the building using an outside tie-in climbing configuration and topped with a 36/40Z-Meter placing boom. In addition, one 28Z-Meter truck-mounted concrete boom pump is used for both the North and South Towers.
JLS continues to push the envelope in industry firsts. They were the first on the West Coast to use the combination of a Putzmeister pin tower and an outside tie-in configuration. During the course of the Skyline project, they have used four Putzmeister universal tie frames positioned along the pin towers as the buildings have climbed higher and higher. This sets yet another record.
“To securely support the tower and placing boom, the universal tie frames are positioned at four different locations along the pin tower,” comments Navarro. “On both of the buildings, the first tie-in occurs at the seventh floor, the second at the 12th floor, the third at the 17th floor and the fourth at the 22nd floor.”
According to Navarro, the first three universal tie frames are eight feet away from the buildings.
“At the 18th floor, the distance from the pin tower to the structures increases because the buildings step back 10 feet,” comments Navarro. “This unique design feature of the buildings means that the tie frame on floor 22 is an impressive 18 feet from the structure, another extraordinary first.
“In addition, we’ve been able to reach a remarkable 300 feet high with our outside tie-in climbing configuration and pin tower technology - an unheard of feat, up until now, in the industry,” says Navarro.
According to Navarro, this is twice as high as JLS has ever been on a high-rise project with their outside tie-in technology.
It’s also the highest an outside tie-in has ever reached in Putzmeister America history, according to Bill Carbeau, Director – Special Applications Business for Putzmeister America.
JLS and Putzmeister America are working closely together to ensure the outside tie-in placing technology and pin tower combination hold up to the job’s demands.
“Putzmeister was always on call to help us if we had any questions during the planning phase as well as in the current execution phase of this project,” notes Navarro.
The Putzmeister America team providing support to JLS includes Carbeau and Walter Knigge, project engineer for Putzmeister America.
“We were pleased to work with JLS in helping to determine how the tower and universal tie frame would work on-site,” comments Carbeau. “They’ve been a long-time and faithful customer to us. It’s our goal to provide every customer with the technical expertise needed to establish the best placing system possible each step of the way. This includes a lot of front-end work even when the customer is only in the proposal stage for a project.”
“We brainstormed together with Putzmeister America on what the best setup, logistically, would be for all of our equipment on the site,” says Navarro. “There was no question that our universal tie frames, pin towers and placing boom were up to the challenge.”
Why the outside tie-in placing system method?
The motivation for using the outside tie-in placing technology versus an inside placing system on the project, was due to the strict timeline.
There was no ideal location for an inside placing system in either of the Skyline towers. Normally, elevator shafts of high-rise buildings are used to house an inside placing system; however the Skyline towers needed their elevator shafts in use as soon as possible, and as a result, they were ruled out for an inside placing system location.
In addition, using an inside placing system that is not in an elevator shaft would mean going back into the building to fill the area supporting the system with concrete after it’s removed and most of the concrete is placed. This could result in project delays for finish trades of the project.
“Putzmeister’s universal tie frame enables us to secure the tower outside the structure, therefore minimizing disruption to other trades inside the building,” notes Ted Rebelowski, Project Executive for Largo Concrete, Inc., the concrete contractor for Skyline.
Staying on Schedule
To place the total 55,000 cubic yards of concrete to the top of both Skyline towers, JLS has their 28Z-meter truck-mounted concrete boom pump at ground level where the concrete is pumped from the boom pump’s SBU hydraulic circuit on the head side. The slick line then travels up via the freestanding pin tower up to the placing boom on either Skyline tower.
To stay on track with the project’s timeline, Rebelowski says an average of 400 cubic yards of concrete on a 16,000 square-foot deck is placed with the placing boom on the Skyline project every four days for each tower. This has been the schedule for placement of concrete since day one.
To date, according to Navarro, JLS has placed about 53,000 cubic yards of concrete with their placing system and pump.
JLS will be on-site until all of the concrete is placed in early 2008. Construction of Skyline’s North and South Towers will be complete in September 2008.