Hoover Dam Case Study: Schedule Recuperation

Hoover Dam Bypass Bridge over Colorado River linking Nevada and Arizona

Design: concrete-steel composite arch bridge

Total Length: 1,900 ft.

Height: 890 ft.

Longest Span: 1,080 ft.

Designer: HDR, Inc. Lyn International for the bridge and Severdrup Civil Inc, for the approaches

Completion Date: November 2010

When completed, this will be the first concrete-steel composite arch bridge built in the United States. The composite design, using concrete for the arch and columns with steel construction for the roadway deck, was selected for schedule and cost control.

The arches are made of 106 pieces, 53 per arch, cast in place 24 feet at a time.

More than 17,000 cars and trucks are expected to use the new bridge daily, a number expected to grow by 50 percent over the next 20 years.

Strong wind gusts across Black Canyon on September 15, 2006 appeared to be the cause for the collapse of the “high-line” crane system used to carry people and materials.

The crane collapse anticipated a two years delay on bridge completion, yet, according to experts, the time recovery is well on it’s way. The schedule recuperation is remarkable considering that the project lost the master crane.