Putzmeister Pumps Play Key Role in Hospital Project Involving Tilt-Up Panel Construction
Putzmeister Pumps Play Key Role in Hospital Project Involving Tilt-Up Panel ConstructionSTURTEVANT, Wis. (September 2004) – The largest construction project in the history of Nevada’s state capital, Carson City, incorporates some of the tallest concrete tilt-up panels in the nation.
The tilt-up construction method is being used along with an unusually high, cast-in-place shear wall.
These techniques are building the $132 million Carson-Tahoe Medical Center, which encompasses a 345,000-square-foot hospital that is 2.5 times the size of an existing hospital, two miles to the north.
Located 40 minutes from Lake Tahoe, Nev., and 30 minutes from Reno, Nev., the existing Carson City hospital serves a regional population of more than 260,000 and faces a growing number of challenges. Since 1998, the facility often has reached census alert – meaning all beds are occupied.
With a bed shortage not an uncommon occurrence, construction of the new medical facility began in November 2003. To construct the interior of the complex, a 63-foot, free-standing shear wall was cast in place. The wall is 2 feet thick.
Tilt-up panels then were installed. The panels measure up to 83 feet tall, 34 feet wide and vary from 10 to 14 inches in thickness. The national record for a tilt-up panel is 92 feet in height. The panels were set on concrete footings 3 feet, 6 inches thick, and 10 feet wide.
“The tilt-up panels are certainly the tallest in the Reno area and are believed to be the fifth highest in the U.S.,” said Jerry Kiger, general manager of Acme Concrete Pumping Inc., Reno. “As far as dollar volume, this is the biggest concrete placing job we’ve experienced in the area.”
Kiger’s company was chosen to place the concrete. He opted to use a Putzmeister 58-Meter concrete boom pump with .20H pump cell because of its long reach and high-volume capacity. The 58-Meter was the only boom pump that could provide the needed reach to pour the tall shear wall.
The reach capability of the 58-Meter also was needed to pour the tilt-up panels. The boom pump was positioned so it did not have to be moved when pumping the largest panels. It delivered an astounding 240 yards of concrete an hour, just shy of its maximum output of 260 yards.
“For quicker completion, our 58-Meter was the only answer because other pumps in our fleet just aren’t capable of pumping that volume,” Kiger said. “There’s no doubt in my mind that the success of the project is due in great part to the high output capability and boom reach versatility of the Putzmeister 58.”
Other concrete placing equipment used on the job included a Putzmeister Telebelt® TB 105 conveyor to conveniently place drain rock and a Putzmeister 32Z-Meter to pour footings and decks.
“Our Putzmeister 32Z-Meter was a godsend for doing the deck because it cut the pour time in half. Because of its Z-boom, we were able to maneuver the tip section farther inside the decks so we didn’t have to drag 400 feet of hose that would have been necessary with a roll-and-fold boom,” said Kiger.
In business since 1989, Acme Concrete Pumping offers an 11-unit fleet of concrete boom pumps and conveyors, all maintained immaculately and distinctly painted turquoise and white. The founder is construction-knowledgeable Lora Tedesco, who saw the need for concrete pumping services in the area 15 years ago. She attributes the company’s continued success to highly capable personnel along with high-performance equipment.
“We worked on this project the entire winter,” said Kiger, who’s been with the company eight years. “Extremely difficult and unusual weather conditions for the area, including snow, rain and wind, did not prevent us from operating equipment and keeping this job on schedule.”
It is estimated that the project will consume more than 25,000 yards of concrete. Capital City Concrete of Carson City supplied the concrete – predominantly a .75-inch, hard-rock mix design.
Tedesco Construction of Reno, which has been recognized with two Golden Trowel awards and a TCA Industrial Building” achievement award, was selected as the concrete contractor. The company formed the panels, floor, walls and footings and assisted in concrete placement and finishing.
In addition, Tedesco was responsible for standing the extremely tall panels, the largest of which weighed more than 300,000 lbs. Tedesco used a 300-ton Manitowoc crane, brought to the area from Los Angeles, to lift the heavy panels into place. Special components were required to stand such large panels. Dayton Superior Corporation, Santa Fe Springs, Calif., handled the task of engineering the specific inserts and bracing.
Ed Javanbakht, tilt-up engineering manager for Dayton Superior, said, “This project had the tallest single-piece concrete tilt-up panels west of the Rockies. Therefore, everything involved with the bracing and rigging required a specially engineered design.”
Although the special inserts involved making a fairly simple modification, the long, 47-foot braces represented a more involved engineering feat. Knee, lateral and in-braces were designed specifically to work together for maximum support when raising a panel.
An R82 factor was determined, resulting in the need for 16 anchors per panel. Each anchor was a T-81 heavy-duty, ground-release insert, more commonly known as an 8-ton swift lift anchor. They are designed to quickly hoist a one-piece concrete slab.
It is critical to raise a panel a minimum of 70 degrees within 40 seconds to avoid undue stress and potential damage.
“Once you start the lifting process, it has to be done swiftly and continuously,” Javanbakht said. “And that’s a difficult task when dealing with such tall panels. Some of the panels were also of the aluminum-channel, strong-back variety, which stiffened the panel for temporary strength when elevating.”
Tilt-up construction debuted in southern California about 50 years ago and experienced phenomenal growth from 1995 to 2000, when the US economy was booming. Today, use of this technology remains relatively steady. For 2003, new tilt-up construction totaled more than 200 million square feet of panel walls, enclosing approximately 500 million square feet of building space.
California, Texas and Florida lead the nation in use of tilt-up construction, while pockets of growth in its use can be found throughout the United States and in Canada.
“Tilt-up requires a leading contractor to make a commitment within a region before the technique becomes known and accepted. In Reno, Tedesco has done an outstanding job,” said Ed Sauter, director of the Tilt-Up Concrete Association.
Hunt Construction Group of Phoenix is the general contractor for the Carson City project. The organization completes about $1.8 billion of work annually with between $6 billion and $8 billion under contract at any time.
Hunt’s responsibility in this project includes one level below grade and three levels above grade for the 180-bed hospital, along with a specialty cancer center. It also includes site improvements and servicing a separate, 18,000-square-foot central plant and on-site parking for 590 vehicles.
The original Carson-Tahoe Hospital opened in 1949 with one doctor, three nurses, one x-ray machine and one laboratory technician, along with a cook and janitor. Today, the staff includes some 185 physicians with more than 35 areas of specialty ranging from oncology, cardiology and neurology to plastic and microsurgery. With the completion of the medical campus in December 2005, the number of staff is expected to total 1,200.
Architect: Moon-Maydras Inc., San Diego
General contractor: Hunt Construction Group, Phoenix
Pumping contractor: Acme Concrete Pumping Inc., Reno, Nev.
Place-and-finish contractor: Tedesco Corporation, Reno
Ready-mix supplier: Capital City Concrete, Carson City, Nev.
Bracing supplier: Dayton Superior Corporation, Santa Fe Springs, Calif.
Equipment: Putzmeister 58-Meter and 32Z-Meter concrete pumps and Telebelt® TB 105