SAN FRANCISCO, CA – T.Y. Lin International (TYLI), a globally recognized full-service infrastructure consulting firm, announces that the Mike O'Callaghan-Pat Tillman Memorial Bridge (also known as the Hoover Dam Bypass Bridge) is complete and officially opened to traffic. TYLI engineers led the design of this landmark span, which now complements one of the foremost engineering wonders of the world – Hoover Dam.
Started in 2004, the bridge is the western hemisphere's highest and longest single span concrete arch bridge, with a remarkable 1060-foot main span. It is also a vital part of a $240 million, four-lane bypass project that reroutes traffic for 3.5 miles from the former two-lane bottleneck on U.S. 93 across Hoover Dam.
"TYLI was privileged to develop this landmark bridge design in the shadow of Hoover Dam." said TYLI Chief Bridge Engineer, David Goodyear. "The twin-rib arch and composite deck design created by TYLI was a cost-effective and creative approach to meeting the environmental impact statement's commitment to complement views of and from Hoover Dam."
TYLI engineers developed rigorous standards for the design of the bridge, including the ability to withstand a 1,000-year earthquake and wind speeds that are 25% in excess of code requirements. Goodyear and his team also made sure that the deck arch of the bridge combined applications that optimized concrete and steel, with high performance concrete used for its stiffness and compressive qualities and steel for its tension and quick assembly during construction. The twin-rib concrete arch features the tallest precast segmental concrete columns in the world. The lightweight steel superstructure allowed for rapid, highline erection and lowered dead load demands on the arch for an efficient, economical design.