Shuffle System Feeds Multiple Placing Boom Projects in Seattle
Servicing 11 different placing boom projects in one metropolitan area on various days and times means utilizing mobile pumps for best equipment utilization. Because resetting form systems on high-rise projects and preparing for large scale deck pours can take days, it doesn’t make sense to leave a concrete pump on site waiting for the next pour when it could be earning revenue on another job. Brundage-Bone Concrete Pumping, headquartered in Denver, has applied their considerable experience to the logistics of supplying 11 placing boom projects in Seattle with a steady flow of concrete by shuttling concrete pumps to the various sites.
One of those projects is Midtown21, a 21-story mixed use midrise in downtown Seattle. The project started in November 2015 with a 5,400 cubic yard mass foundation pour on the half-block site. “We had several long booms in place on a Saturday morning and finished in about eight hours,” according to Brett Young, Brundage-Bone’s General Manager for concrete pumping in Washington State. The next portion of the project was the six-level underground parking ramp that was also boom pumped to bring the project up to street level. After boom pumping the first floor, the pumper switched to a Schwing SPB 37 separate placing boom mounted on a Peri climbing form system.
Ready-mix access to the site, which is only slightly larger than the building’s footprint, means getting in and out fast as the location is within two blocks of an Interstate. Regular boom pumping from the street would cause too much congestion with the city’s retail core and largest concentration of four-star hotels within blocks of the site. At 300-feet, the building’s height would exceed a boom pump’s reach.
The placing boom, powerpack and head section are mounted on a Schwing zero elevation base that is clamped to the form system and centrally located on the site. With 120-feet of reach, the four-section boom reaches 99% of the 19,200 square foot floor plates. With the form mounting, the boom operator enjoys a vantage point from above the deck pours for precision placement. The Roll and Fold™ design keeps full articulation on the working side of the boom, which allows operators to maneuver the boom as necessary. The SPB 37’s hydraulic powerpack is a separate piece weighing 5900 pounds that allows a low 13,000-pound picking weight for the boom. With 550 degrees of rotation the boom gives operators maximum flexibility when maintaining multiple pours in a day. In mid February, the company was pumping level thirteen. The deck forming is always one level behind the concrete core as the building climbs one floor per week.
According to Young, “We pump the core and columns in one day and the deck on the second day.” The 650 yards of concrete required for the weekly pours are pumped by the company’s Schwing S 32 X truck-mounted concrete pump with placing boom. The pumps are equipped with the 2023-5 pumpkit offering 211 yards per hour maximum output. The pump can be switched to a high-pressure setting if the job requires it. This Schwing model also features the M Rock Valve with axial bearing that allows the valve to shift with less friction in high pressure pumping situations. Brundage-Bone project managers keep to a schedule of pours in order to dispatch six of the S 32 X concrete pumps on a regular basis to the various placing boom projects in the Seattle area. Some project pour schedules are established six months in advance.
“We have become very efficient at hooking up the pump to our slickline,” Young says, “We add a high pressure outlet with six-inch elbow that can rotate to either side and then add a six to five reducer. It takes one guy only a few minutes and we are hooked up and ready to pump.” The separate placing boom operator on the upper decks communicates by radio with the pump operator to keep the rate of pour on pace with the finishers. Clean out is on site in only ten minutes. “Access to the Rock Valve is very good and we don’t need much water which is always appreciated.”
Depending on the timing and the company’s work schedule, the boom pump may be dispatched to another job after pumping on the high-rise project. “We are able to utilize the 32-meter on commercial and residential jobs in the afternoon after pumping the Midtown project in the morning,” Young notes. Placing boom operators will often hitch a ride to the next job if the boom pump is going to hook up to another high-rise placing boom. One of Brundage-Bone’s current projects in the area is using three Schwing SPB 37 placing booms and seven mast locations. With 100,000 cubic yards of concrete to be poured, there are always pumping opportunities.
The shuttle system is designed for high equipment utilization; important for a company that has 500 pieces of equipment in 55 cities and 50 placing booms in the air at any one time. Choosing the right equipment is also important. “The 32-meter is ordered on 40-percent of our boom pump projects,” according to Brundage-Bone President and CEO Bruce Young, “So that was a natural choice for a pump that has to do double-duty. The Schwing unit has a powerful pumpkit which is important for our high-rise projects.”
Brundage-Bone’s success shows that their emphasis on high equipment utilization is working. But concrete pumping is not always predictable. “We had to perform some unexpected maintenance on the big stationary concrete pump on a large separate placing boom project,” Brett Young explains, “In order to stay on schedule we hooked one of our Schwing 32 boom pumps into the slickline and pumped 100-feet down, 700-feet horizontally and 100-feet up to our separate placing boom and it worked fine.”
Concrete work on the Midtown21 project is to be completed by mid-2016. Downtown Seattle’s construction boom continues with a record level of investment heading into 2016. There are currently 39 projects under construction totaling $3 billion in construction value. “The real takeoff for us is the commercial market,” says John Hudek, Brundage-Bone’s chief financial officer. “In Denver and Seattle, we see a lot of mixed-use—retail on the ground floor with apartments or condos above.” On the technical side, he adds, “We emphasize what we can do for our customers like having mobile pumps that move on and off high-rise projects so the equipment doesn’t get in the way when it is only needed a couple days of the week.”
Owner: Trammell Crow Company’s Seattle Business Unit and Metropolitan Life Insurance Company
Architect: LMN Architects, Seattle
General/Concrete Contractor: Balfour Beatty Construction US, Seattle
Concrete Pumping Contractor: Brundage-Bone – Seattle, Kent, WA
Equipment: Schwing SPB 37 separate placing boom with zero elevation X-Frame mounting, Schwing S 32 X truck-mounted concrete pump with placing boom