Press Clippings
Western RE News
September, 1998

World's Largest Seismic Base-Isolated Hospital

The joint venture of McCarthy/Obayashi has finished, on schedule and within budget, construction of Arrowhead Regional Medical Center, the world's largest seismic base isolated hospital. The $270 million project is located in Colton.

Begun in January 1995 to replace the existing San Bernardino Medical Center, the nearly one million square-foot medical center includes a six-story, 367,722 square-foot patient tower; a 480,878 square-foot diagnostic and treatment center; a 102,203 square-foot mental health center; and a 21,845 square-foot central plant. Bobrow/Thomas and Associates of Los Angeles were the executive and design architects in association with Perkins & Will of Chicago.

“We have a structurally safe and sound building here that will serve the community and the county well for many years to come. From the beginning, the design and construction members worked as a team to meet the challenges created by the structure's unique design, complexity and magnitude. This teamwork helped to keep the project on schedule and within budget,” said Arrowhead Regional Medical Center Chief Executive Officer Charles R. Jervis.

The new medical center is the first facility to use a combination of hydraulic viscous dampers and elastomeric base isolators to absorb the energy generated during a seismic event and protect the building's structural integrity. This technology can best be explained by imagining a building in a bathtub: During an earthquake, all four sides of the bathtub can move, however the building, because of its mass, remains stationary.

Despite the technological complexity of constructing a building designed to withstand an earthquake of 8.3 magnitude and be self-sustaining for 72 hours, McCarthy Project Director Dean Piles said the project's greatest challenge was a logistical one due to its magnitude.

“The sheer size of the project was our biggest challenge,” Piles stated. “There are changes in every project, however, the size of this project meant that changes were multiplied. We met our original completion schedule objectives while still handling more than 7,000 questions that resulted in hundreds of small but critical changes to the project,” he explained.

During peak construction time, more than 650 field workers and 120 engineers, project managers, project superintendents and administrators were on site, as well as 70 design and engineering construction managers and inspectors. Material statistics further indicate the project's magnitude including utilization of 18,100 tons of structural steel 70,000 cubic yards of concrete and 5,000 tons of rebar.

Arrowhead Regional Medical Center is located just nine miles from the San Andreas Fault and two miles from the San Jacinto Fault. The 373-bed facility, to be operational this fall, will be a fully equipped trauma room, mental health and tertiary care center. It will be one of the largest trauma centers in Southern California. It also will serve as the major burn center between Phoenix and Bakersfield, Los Angeles and Irvine, California.

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