An Educated Decision
A four-section separate placing boom pours all of the structural concrete on the tower using 93 feet of horizontal reach.
Proving that concrete pumpers still need to be ready to educate the market, Champion Concrete Pumping Inc. convinced a skeptical general contractor to let them use a separate placing boom and pump combination on the second tallest structure in Coeur d'Alene, ID.
Parkside is a recently topped-out, 20-story condominium tower with views of Lake Coeur d'Alene located next to a park of the same name. Champion, with offices in Coeur d'Alene and Moscow, ID, Spokane, WA and Missoula, MT, has served the area since 1986. General contractor Robert B. Goebel Inc., one of Spokane's largest contracting firms and a longtime user of Champion's services, had to be shown the benefits of putting a separate placing boom on the project.
"The square footage required about 300 yards of concrete per floor," said Roy Thompson, Champion co-owner, "Our separate placing boom presented a very practical and efficient method of distributing the ready-mix."
Terry Goebel, co-owner and CEO of the general contractor, didn't disagree, but "I have a little Missouri in me, so I needed to be shown." Champion used photos and a video of a structure that had been pumped in Coeur d'Alene with the company's separate placing boom to help Goebel make an educated decision. Since Parkside topped out, Champion has gained a convert.
"It was extremely efficient and didn't get in the way, and it was always there when you needed it," Goebel said.
Illustrating the Benefits
|The 20-story Parkside condo tower went up quickly after the general contractor was convinced to use the separate placing boom method.|
Champion owns two Schwing KVM 32 XL truck-mounted concrete pumps with detachable placing booms in addition to a range of Schwing boom pumps from 17 to 47 meters and a fleet of Schwing trailer pumps. Champion flew both of its booms and mounted them on the mast at Parkside on separate occasions before the first yard of concrete was pumped, to familiarize its crews and to make sure everything would go smoothly if a backup was needed.
The pumper's willingness to illustrate the benefits of the separate placing boom paid off in winning over the general contractor.
"What I thought would be a big deal turned out to be a non-event," Goebel remarked. "I was a Doubting Thomas, and now I'm amazed at how quickly the boom could be detached, flown and hooked up." The Goebel crew got so comfortable with the method, they began raising the mast and extending the pipeline between pours.
"The willingness of Champion's people to demonstrate this method to us is why they pump 90 percent of our work," stated Goebel.
Pete Reed, president of finishing contractors Reed Concrete Co. Inc. in Coeur d'Alene, mirrored Goebel's comments on the use of the separate placing boom.
"It was the first time we had experienced a boom on the deck so we were curious, and we ended up tickled to death," Reed said. "We weren't dragging hose and got by with a smaller crew." Even with less labor, Reed estimated that the finishers were off the 12,000-square-foot decks earlier than normal.
"We would start at 6 a.m., leave by two o'clock and by four o'clock they would be pouring the columns and core walls." Reed Concrete performs flatwork, tilt-up and large commercial work in the Coeur d'Alene area.
Starting at the Bottom
Before the separate placing boom debuted on the project, Champion pumped the foundation walls and below-grade parking structure using 39- and 47-meter Schwing boom pumps. At the ground floor, the 47 took over using its Overhead Roll and Fold boom to pump out the first two floors using its combination of 139 feet seven inches horizontal and 151 feet three inches vertical reach.
"That 47 can get me over 150 feet vertical reach when I need it. We love the tight footprint of the Super X outriggers combined with extra two meters of reach of the 47SX. The 4 1/2-inch pipeline doesn't give us any problem at all, and we really love the extra reach," Thompson said.
One mast was positioned strategically on the structure and allowed the entire deck to be placed from one location with the separate placing boom. The KVM 32-meter boom reaches to 93 feet horizontally.
After the test mounting of both their booms, flying and securing the boom to the mast was routine for Champion's crew. The boom mounts with four pins to mast or truck, and the hydraulic powerpack travels with the assembly.
The boom and powerpack weigh 13,700 pounds, which was within the capacity of the tower crane on the project. Champion's 32XL detach is a one-piece boom. Split booms are available for those situations where crane capacity is limited. The split boom allows it to be picked up in two sections each weighing 7,250 pounds.
"George Wilke is a man with 20 years experience that I put on all of our separate placing boom projects," Thompson said. "George and all my operators are ACPA-certified."
The mast was inserted into openings in the decks using two floor frames, pins and wedges. The openings needed for the mast are the smallest in the industry at 37 inches square. The opening requires a plus or minus 3/8-inch tolerance to accept the floor frame.
As the building rose, the tower crane lifted the mast and the floor frames and repositioned for the next deck pour. Pipeline sections were added to continue to feed the boom from the truck-mounted pump at ground level. Both of Champion's truck-mounted pumps with detachable booms are equipped with Generation Two 2023-5 pumpkits with Multi Port Shifting and axial bearing Rock Valves for high pressure pumping. By timing the shifting of the Rock Valve precisely with the movement of the material cylinders, MPS assures smooth flow of the concrete to the boom. Another benefit of this system is quieter operation which can be an asset in the tranquil setting of Coeur d'Alene.
Ease of Operation
Concrete design for the project was a seven-sack mix with flyash, 3/4-inch aggregate and super plasticizer, according to Craig Matteson, quality control manager for supplier Central Pre-Mix with locations around the Northwest. He said the concrete reached 3,000 psi in three days to meet stressing requirements, 5,000 psi in 28 days, and 6,800 psi was the average 28-day strength.
"The pump easily maintained the yardage all the way up to the twentieth floor," Thompson said. Typically a 300-cubic-yard floor was poured in four to five hours on the Parkside Tower. This level of production and the ease of reattaching the boom to the pump allowed Champion to use the 32-meter for pours on other projects in the afternoon. Cleanout of the pipeline and boom was accomplished with a diversion valve at ground level that routed residual concrete from the vertical line into a waiting ready-mix truck.
After the successful completion of the Tower last fall, the boom was detached for the last time and reunited with the pump. Goebel elected to handle the disassembly of the pipeline and mast.
"They became so comfortable with the ease of moving the mast, and it was cheaper for their crew to do it than for us to come back. It was sitting there ready for us to pick up," Thompson recalled.
Champion moved on to other projects until the call came from Goebel asking if Champion had a trailer pump available that could be flown onto the roof of Parkside. Champion is a dealer for the line of Schwing trailer pumps.
"They had some concrete requirements inside the core which was already covered," explained Thompson, "so we brought one of our Schwing 750-18 trailer pumps to the site, and they positioned it on the roof. From there they craned up the concrete and we pumped it from there."
All in a day's work for a concrete pumper that recognizes customer service is the key to success. Besides providing concrete pumping to its markets, Champion also performs slabjacking, shotcreting and conveyed material delivery. The partners in the business, Roy Thompson and Dave Bertsch, are current or past ACPA board members, showing they serve not just their contractor customers but also the members of the American Concrete Pumping Association.