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Just how does one make a large structure resistant to one of the most damaging forces of nature? That’s the central challenge at hand for general contractor Andersen Construction as it embarks on a $50 million expansion of Oregon State University’s Hatfield Marine Science Center in Newport.

A ground-breaking ceremony last week kicked off a project several years in the making. OSU is hoping the new world-class research facility will attract hundreds more full-time students to its growing campus on the Oregon coast. The structure also is planned as just the second vertical tsunami evacuation site in the United States.

Portland’s Yost Grube Hall Architecture, a firm currently working on a U.S. embassy in Mozambique and another in Turkmenistan, designed the new OSU facility. It will actually be a pair of steel-framed buildings linked with a seismic joint. The taller of the two will include the evacuation site, and be built to withstand a magnitude 9.0 earthquake and a resulting tsunami wave up to 31 feet in height.

Combined, the two buildings will be some 72,000 square feet. The rooftop evacuation site, 47 feet above ground, will have room for up to 900 people.

鈥淲hat we heard was that there needed to be a vertical evacuation feature, because not all people can walk the 12 to 20 minutes that will be required to get out of the area (in the event of a tsunami),鈥� said Steve Clark, OSU vice president for university relations and marketing. 鈥淪o we (planned) the building with the idea that this would serve not only as a resilient building and sustain the impact of the earthquake and the inundations of the waves that come into the bay, but also serve as a point of relief for evacuation for those who can’t get to Safe Haven Hill.鈥�

No existing facility is like the one now being built, KPFF Engineering structural principal Josh Richards said. The only other vertical tsunami evacuation facility in the United States was built in 2015 for the Ocosta School District in Westport, Washington, and it is distinctly different in design and capability.

鈥淭here are no current examples that the facility is explicitly modeled after,鈥� he said.

The latest expansion plans were revealed by OSU in November. Set for completion in fall 2019, it will feature a three-story academic and research wing, along with a two-story community space, an auditorium and laboratories. An emergency ramp will connect the ground level with the top of the auditorium and the academic wing’s roof. There, the evacuation site will provide space for people unable to reach Newport’s Safe Haven Hill a half-mile south of the science center.

Following widespread criticism in 2016 that the site was unsafe for its intended purpose, OSU President Ed Ray appointed a committee to come up with additional safety requirements for the new facility. As a result, the proposed building had to be able to survive a magnitude 9 earthquake and a tsunami expected to move at an estimated 30 mph.

But making this innovative building come alive is no ordinary design-and-build job.

鈥淥h, that’s for sure,鈥� Andersen Construction Superintendent Mark Reusser said.

His company is tasked with building the Hatfield expansion on a man-made sand spit that already holds the rest of the science center, as well as the National Oceanic and Atmospheric Administration’s Marine Operations Center – Pacific. This presents some serious geotechnical challenges because during an earthquake local soils are expected to liquefy and cause widespread surface instability.

The key to withstanding a magnitude 9 quake, Richards said, comes from honeycomb-style, deep-soil foundation columns reaching 100 feet or more below the sandy surface. Instead of traditional support columns, the overlapping grid-like foundation is mutually supportive when experiencing lateral stress, such as that caused by an earthquake or tsunami. Even as the soil liquefies, the entire building is designed to remain intact and upright.

In addition, deep soil mixing is also in play. Used in Japan since the 1950s and in California since the ’70s, this technique uses cement-like materials to fill or blend with native soil. It increases soil strength and compressibility, allowing for greater stability during a seismic event.

鈥淭here’s about a million pounds of cement that’s going to be mixed in the ground to complete the deep soil mixing for the foundation,鈥� Reusser said. 鈥淭hat sets that building up so that it won’t float away. It can’t wash away. You can’t wash the ground out from underneath it and it can’t settle too much.鈥�

The deep soil mix used for the Hatfield project consists of a cementitious grout mixed with existing soil through an auguring process, Richards said. This creates hardened soil columns, which in turn support concrete spread and mat footings as part of the deep soil grid.

鈥淭he perimeter deep soil mixed columns also protect from soil scour and loss of support that would occur around the building during the tsunami event,鈥� he said.

鈥淚t’s essentially a grid or a matrix type of structure that goes down that deep,鈥� added Jerry Waters, associate principal and senior project designer for Yost Grube Hall. 鈥淭hey (foundation supports) are all connected, and it’s a grid 鈥� you can kind of visualize a honeycomb system, so it will act as one big monolith.鈥�

After an earthquake’s tremors subside, a tsunami wave 30 feet or taller would be expected to strike the new facility. Both buildings will feature steel framing with concrete core walls and slabs built to resist lateral seismic and tsunami loads, Richards said. Designers used Federal Emergency Management Agency documents produced after the 2011 Fukushima nuclear disaster in Japan to create a pair of structures able to provide plenty of redundancy against collapse.

鈥淭he criteria used are the same as required for U.S. embassy or other federal facility designs,鈥� Richards said. 鈥淚t includes removing select columns and other large load-carrying elements in the structure, and requires adequate detailing and member design in order to maintain load path continuity for these conditions.鈥�

That will be critical for any quake survivors taking shelter atop the building.

鈥淚t has more robust than normal connections,鈥� Waters said. 鈥淏ut at same time the steel has a better capability of sort of some flexure compared to concrete.鈥�

Even with substantial modeling and testing, only a real earthquake will offer proof of survivability. But designers and engineers are confident in their work.

鈥淔irst, you have to withstand the potential seismic event, and then you have to be resilient enough to potentially withstand a tsunami,鈥� Waters said. 鈥淎nd, again, it’s somewhat unknown, but obviously there has been quite a bit of data used to simulate and estimate the magnitude of damage the building will receive.鈥�

The final result should showcase world-class engineering as well as maintain Oregon’s role as a premier destination for scientific research, Clark said.

鈥淲e wanted to demonstrate a commitment to Oregon’s coast and throughout the world, that, actually, this can be the location for important public features,鈥� he said. 鈥淎nd if they’re built correctly, and in the right location and in the right way, our coastlines aren’t closed for business.鈥�