The 550-ft-tall High Roller observation wheel—the largest in the world—anchors The LINQ retail area located on the Las Vegas Strip, serving as the development's main focal point.
The apparatus is very much like a bicycle wheel, according to Arup. It consists of a single 6.6-ft-wide tube-steel rim, hung from 128 locked coil cables. The 28 cabins each weigh 44,000 lb and sit around the outside of the rim, each held by a single slewing bearing. Grand Junction, Colo.-based Leitner-Poma of America Inc. was the design-build cabin contractor.
The hub and spindle at the center of the wheel are supported on four legs, which cant inward to land on a narrow footprint, smaller than the wheel itself. A single brace leg reaches east from the top of the legs. Each of the support legs and the brace leg lands on a monolithic concrete plinth and is filled with concrete for the bottom portion in order to provide resistance to accidents, attacks or other potentially disastrous occurrences. The plinths tie into pile caps with piles running down 60 ft to a layer of caliche.
American Bridge devised the erection methods to maximize the strength of the cranes. The lift was done in multiple stages. The first involved placing the hub-bearing-spindle end assembly onto a sled and towing it across a temporary truss. A portion of the spindle was also threaded into the hub in a two-crane maneuver.
The rim was installed using 50-metric-ton chainfalls hung from a specialized platform at the hub. The partial rim was rotated and held by a custom hydraulic rotating mechanism supplied by Enerpac, Manomee Falls, Wis. The incomplete wheel was supported by nine pairs of specially designed temporary struts. Cable tension was determined by measuring frequency when vibrated, according to Arup.
For the installation of the bearings, SKF and Arup simulated the steps in the installation in finite element analyses to confirm proper fit-up in the final condition. On site, American Bridge and SKF worked together as one team to implement this procedure.
Judges lauded the precise engineering work required, including maintaining bearing tolerances of just 100 microns.
Las Vegas High Roller
Las Vegas
Key Players
General Contractor American Bridge Co., Coraopolis, Pa.
Owner/Developer Caesars Entertainment, Las Vegas
Scheme Architect The Hettema Group, Pasadena, Calif.
Platform Architect Klai Juba Wald, Las Vegas
Structural/MEP Engineer Arup, San Francisco
Subcontractors Schwager Davis Inc., San Jose, Calif.; Leitner Poma of America, Grand Junction, Colo.; W.A. Richardson Builders, Las Vegas; Bombard, Las Vegas; SME, West Jordan, Utah; Heywood Engineering, Reno, Nev.
Post a comment to this article
Report Abusive Comment