"The floating cabin design opens the sight lines and creates a flying sensation," Codiga says.

The orb-shaped capsules have 225-sq-ft floor plates capable of accommodating 40 people or a 12,000-lb load capacity. Riders enter and exit the High Roller from a three-level platform structure that also houses wheel drive and control systems. The air-conditioned cabins each feature two bench seats and eight flat-screen televisions, plus double doors and an iPod dock. A specially devised single mounting ring supports and rotates wheel cabins, keeping them parallel to the ground for a comfortable ride; previous observation wheels relied on two slewing bearings to maintain vertical orientation.

Going Vertical

Taking the High Roller vertical is a mammoth challenge. Two years in design, the project broke ground in early 2012 and is well ahead of SkyVue, a competing Las Vegas Strip observation wheel project. Construction on the $300-million SkyVue has been stalled for months due to funding issues. Even if built, SkyVue's planned 500-ft height would still be slightly lower than the High Roller.

American Bridge is using a 750-ton Liebherr 1750 crawler crane with 367 ft of boom and a 1-million-lb counterweight as its onsite workhorse, along with a secondary Manitowoc 2250 access crane. Las Vegas-based Dielco Crane Service is the crane supplier-operator.

"Due to site constraints, the hub, spindle and bearing unit was erected in three pieces using a 250-ft-tall custom falsework truss between the legs and three 50-ton chain hoists," says American Bridge project engineer Daniel Schwarz. "Segments were trolleyed into place and bolted together."

The wheel rim is being assembled in a similar fashion. Twenty-eight sections will be hoisted into place from the six o'clock position using 250-ft-long radial erection struts; the 60-ft-long, 45-ton tubular steel rim segments are hung vertically and then bolted to the advancing rim section with a collar splice.

"The wheel will be rotated during construction by a temporary drive system that utilizes jacks and a pulling frame," explains American Bridge project manager John Callaghan. "As each segment and cable spoke section is erected, the wheel will then be turned and another segment erected, and so on."

High Roller construction has entailed an international mobilization effort. Steel fabrication took place in Shanghai, China, and Muroran, Japan. Other wheel components hail from France, Italy and Germany.

American Bridge coordinated three-dozen heavy haul tractor-trailer deliveries to the jobsite from the Port of Long Beach, Calif. Overall, Linq will see 800 craftsmen on site during the peak of construction activity, including 100 tradesmen for the wheel.

Ultimately, the High Roller has the theoretical capacity for 10% of the current world population to enjoy a ride during its 50-year lifetime.