Large Boom Pump Makes Awesome Moves Under People Mover December 2000

Unique Design of Putzmeister 52Z-Meter Boom Is Key in Detroit Mat Pour

The right equipment, pumping company, contractor and ready-mix supplier made orchestrating the initial pours on the Hudson Premier parking garage a fast and efficient task. There were, of course, many obstacles to get this project off the ground in a timely and cost effective manner.

In a bid to continue restoration of the Detroit metropolitan area, a number of construction and renovation projects have been ongoing to re-energize the city, now called the Renaissance City. One such project was the creation of a new underground parking structure on the unoccupied site of the imploded Hudson Department Store warehouses.

This new structure will service nearby venues such as the new Ford Field Football stadium, Comerica Park, the Opera house and the renovated Fox Theater. The current site of the parking structure is especially unique, as it is being designed to handle the construction of an 18-story office building atop it some day.

When completed, the Hudson Premier parking garage will be a subterranean structure comprising four stories. Baker Concrete of Canton, Mich.; Pumpco, Inc. of Taylor, Mich.; and Koenig Fuel and Supply of Detroit, were contracted to pour and finish the parking structure's base slab. In total, the mat pour constituted an average thickness of 5 feet (1.5m) and over 20,000 cubic yards (15,200m3 ) of concrete in the eight major pours that will be needed to complete it.

Two minor pours added Two minor pours not included in the original eight were for slabs measuring 3,600 square feet (334m2) and requiring over 600 cubic yards (456m3 ) each. These were needed to support two individual tower cranes, which would be erected and used for final job completion.

However, before any work could be started, a few logistical questions had to be addressed. Since the construction site was located in a very busy part of downtown Detroit, many issues regarding traffic and site access were considered. Due to the many unique challenges that faced all of the sub-contractors, it was advantageous for all contractors to have extensive knowledge and experience in dealing with challenging site conditions.

John Fuller, project manager for Baker Concrete said, "The challenges the Hudson Premier project presented were not unusual for us, especially when you're a contractor working in a large metropolitan area such as Detroit."

Several pre-job meetings held One way to minimize the potential problems that most definitely would arise was to coordinate with everyone associated with the project right from the beginning. This was the only way to help ensure an organized approach when the call for action was sounded. According to Peter Fredericks, president of Koenig Fuel and Supply, "Several pre-job meetings were held to plan the flow of over 75 mixer trucks for the first major pour. These pre-job planning meetings allowed the pours to commence without logistical problems."

The initial pour encompassed over 4,000 cubic yards (3,040m3 ) of 5000-psi (345 bar) air entrained concrete and 675 cubic yards (513m3 ) of 5000-psi (345 bar) regular mix with super plasticizer. Adding to the equation was dispatching mixers from five different batch plants.

Another issue was that on one side of the job site lay the People Mover, an elevated monorail type system designed to move people efficiently around the streets of downtown Detroit. The People Mover borders Farmer Street on the east side of the site and had been damaged in the implosion of the Hudson warehouse structure. Because of this, legislation was drafted limiting how close equipment could come to the track system.

Permits also had to be secured to allow Pumpco, the pumping contractor, to position the pump within 15 feet of the People Mover, while maintaining a minimum of one foot of clearance between the boom and the monorail structure.

With low overhead clearances of around 22 feet, the People Mover provided a new challenge to the team when trying to reach the site with standard equipment. Since the People Mover ran the entire length of the Farmer Street side of the site, the only way to access the tower crane pad pours was to position a piece of equipment as close as possible to the track of the monorail.

52Z meets new challenge The Putzmeister 52Z straight truck-mounted concrete boom pump was brought in due to its versatile 5-section, Multi-Z boom configuration. This unique design and low unfolding height enabled the 52Z to reach under and unfold, clearing the People Mover and obtaining the reach required. In addition, it helped minimize the disruption of street closures and the need to reroute city traffic.

Jerry Donnelly, branch manager of Pumpco said, "Without the Putzmeister 52Z, there would have been no other way to access the one side of the site and complete all the pours."

With the 52Z set up under the People Mover on one street, the Putzmeister 52Z semi-trailer, 42X and 32M boom pumps surrounded the job site on the other three sides. Working together, these units proved to be the ideal combination for placing concrete quickly and efficiently.

The combination of the four Putzmeister boom pumps allowed the contractor to pump on average over 500 cubic yards (380m3 ) an hour for the first 4,000 cubic yard (3,040m3 ) pour. With this output and the special characteristics of the Putzmeister 52Z, they were able to minimize road closures to only one road and were able to feed the boom pumps without delays. Of course, all this was possible only through the synchronized efforts of those involved.

Two of eight major pours completed To date, two of the eight major pours have been completed on this multi-million-dollar project. All subsequent pours will be handled in the same fashion and will require the highly synchronized organization that the first few pours demanded.

Through planning and use of detailed routings, the combination of people and equipment allowed Pumpco and its partners to run an efficient pumping operation on-site and provide the contractor with the performance required … of course, with special thanks to the unique "five-section" 52Z boom pump.

General Contractor: Capitol Construction - Detroit Concrete Contractor: Baker Concrete - Canton, Mich. Concrete Pumping Contractor: Pumpco, Inc., - Taylor, Mich. Ready Mix Supplier: Koenig Fuel and Supply - Detroit Pumps: Putzmeister 52Z-Meter semi-trailer, 52Z-Meter straight truck, 42X-Meter, and 32M truck-mounted concrete boom pumps.

Note: Pictures supplied courtesy of Jerry Donnelly of Pumpco, Inc.