Setting an Amazing Pace - Two 13-story Hudson River Buildings Top Out in Record Time February 1999
Putzmeister America introduced the Putzmeister 32Z-Meter, a completely redesigned truck-mounted 32-meter concrete pump, at World of Concrete '99. This new lightweight boom pump, with a 105-foot vertical reach, features an exclusive Multi-Z boom design and a larger, more robust pedestal. The patent-pending boom design delivers a faster and more efficient setup because the boom doesn't have to be completely unfolded to begin the pour. This advantage means operators are immediately ready to place concrete – even right next to the truck. The unit's Multi-Z boom also provides a low 25-ft. 3-in. (7.7 m) unfolding height, making it ideal for use under low height structures and in tight areas.
Many contractors would say that a three-month construction schedule to top out two 13-story, 15,000-square-foot apartment buildings is aggressive. But with a team of experienced concrete pumping veterans, 25 masons and laborers and two dependable concrete boom pumps, Forsa Construction finished the Hoboken, N.J. development, The Shipyard, in record time.
Like many contractors on the East Coast, Forsa took advantage of the unusually mild November and December weather to beat the Northeast storm season. Nonetheless, finishing this mixed-use development in time for the New Year was a bit amazing.
Steve Crevani, Jr., Forsa's general manager, admitted that since they specialize in high-rise buildings, they have a jump on most contractors for this kind of work. In addition, after they finish the pile caps and columns, they have a system that keeps them pouring a new floor every two days. "We're talking about huge buildings here," said Crevani. "One is 15,000 square feet and the other is 20,000 square feet." In addition, Forsa completed a three-story, 42,000 square foot parking garage situated between the high-rises, too.
The noteworthy aspect of this job was the speed in which they finished each floor, said Crevani. "Using two Putzmeister concrete boom pumps, we poured as much as 100 cubic yards of concrete an hour," he explained. "That's about 40 to 50 yards per hour faster than if we used a crane to deliver the concrete". For this job they used a Putzmeister 42-Meter and a brand new 36-Meter Putzmeister truck-mounted boom pump. "You can't match the speed of a pump."
To make the concrete set up faster, they also used a mix of super plasticizer and accelerator. In addition, they poured each floor in one shot. Depending on what height they're at, Crevani said it takes between 4 1/2 to 6 hours to finish a floor. "So, by 1:00 p.m., we were finished pouring over 500 yards of concrete," he added. "With each 20,000-square-foot floor, we needed more than 50 concrete trucks to feed the boom pumps."
Altogether, they poured a tremendous amount of concrete on this job. According to Crevani, they used approximately 20,500 cubic yards for the two high-rises and parking garage. "If we used cranes, this job would have required overtime - and with shorter winter daylight time, we never would have finished on schedule." In fact, pumper trucks are about all Forsa uses now. "We're on our third Putzmeister truck now. They're dependable, and maintenance and wear and tear are minimal."
When the job is complete later this year, he said tenants will enjoy a view of the Manhattan skyline across the Hudson river or strolling along the grassy, tree-lined rooftop park on the parking garage - and they'll be glad Forsa Construction beat Mother Nature at her own game last winter.