Cianbro Construction prides itself on handling projects that are a bit out of the ordinary. In the past, the company has done everything from the construction of floating offshore wind turbines, to the installation of 230 miles of electrical transmission lines, to the replacement of thrusters on a massive oil drilling ship. So it should come as no surprise that, when the search was on for a contractor to erect an observation wheel near our nation’s capital, Cianbro was at the head of the list.
But the logistical challenges for the project — its construction at the end of a long and narrow pier, for example — taxed even Cianbro’s impressive specialized-equipment inventory. To get the access and reach they needed for several facets of the job, the company turned to Genie which had just introduced its SX-180 boom lift with 180 feet of vertical reach. Armed with that newfound capability, the project is proceeding on pace and, despite some early weather-related challenges, the attraction should be open in time for Memorial Day 2014.
Work on the Capital Wheel started with the installation of a 150-ton steel grid base structure. Fabricated by Cianbro at its Baltimore yard, the individual components for the base were sent by barge to the Potomac River site. While that ultimately proved to be the best method for transporting such material, there was a point when the decision to do so looked sketchy at best, says Dreher.
With construction of the base completed, the structure’s tower legs were erected, followed by installation of other ride components such as the axle, spokes, ring beams, and lights. That pre-determined construction sequence — and being located at the end of a 600-foot pier — essentially dictated the manner in which the balance of the project could proceed. While the actual height of the tower legs and components to be assembled there could, in a normal setting, be reached using one of Cianbro’s existing standard-sized booms, access was another matter entirely, says Dreher.
“If we were putting this up on land under normal circumstances, we’d have no issues accessing the axle and spoke connections with a standard 85 foot boom lift,” Dreher says. “But, because we are on a pier and had to first install the base steel structure, we were left with only two spots from which a boom could operate in order to have access to both sides of the wheel. And on one of those sides we are set back more than 85 feet and need to reach 90 feet into the air over the top and in between the tower legs — far more than a conventional piece of equipment could achieve.”
Cianbro’s timing could not have been better as Genie was just debuting its SX-180 boom lift, which it bills as the highest reaching self-propelled boom in its product lineup. Because of the then-limited availability of the tool, Cianbro contacted US Markets, Inc., an Elmhurst, Ill.-based equipment provider who is working closely with Genie to introduce the SX-180 into the marketplace. According to Chad Cochrane, US Markets’ general manager, they were able to deliver an SX-180 within Cianbro’s tight time frame.
The Genie SX-180 was quickly loaded and delivered to the National Harbor site. Cianbro’s Dreher says its impact on the job was felt immediately.
“The Genie boom, which we call ‘The Monster Lift,’ has nicely filled that gap between what our 135-foot lift can and can’t reach,” Dreher says. “It was instrumental in the assembly of the tower legs themselves, but one of the most crucial areas of the construction involves setting the wheel’s ‘spokes’ into the hub or axle. The SX-180 boom lift allows us to get up and over the tower legs and then reach in to the axle area to do each connection.”
That process is aided considerably through use of the unit’s 10 foot rotating jib. Dreher says the jib and work platform are ideally sized for their needs and the articulation feature has been invaluable for maneuvering into position.