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In 2015, after The New Yorker published a and the toll it could exact in the Pacific Northwest, seismic resilience became a hot topic in Portland.

鈥淚 was walking down the street, and two people were talking about earthquakes,鈥� said Reid Zimmerman, associate structural engineer at KPFF Consulting Engineers. 鈥淚n general, it was very positive. I definitely think that it was a plus. It seems as though owners of buildings are thinking about designing for seismic resilience.鈥�

The science behind such efforts has advanced over the past few decades. Now, the most cutting-edge technologies involve high-tech concrete and metal that can remember their shapes.

鈥淭he philosophy has been that (structures) should not collapse (in an earthquake), which is wonderful,鈥� said Saiid Saiidi, a professor of civil engineering at the University of Nevada-Reno. 鈥淏ut (structures) can be severely damaged. That is the accepted risk.鈥�

Saiidi has spent 15 years researching ways to minimize quake-related damage, primarily in bridges. One of his discoveries is a smart memory alloy that bends and sways with a quake, and then returns to its original shape once shaking stops. The new alloy is being used in a bridge in Seattle, and will ensure the structure is usable almost immediately after a quake, Saiidi said. The problem is that such modern technology is very expensive.

鈥淭he shape-memory alloy systems have been difficult to make economically,鈥� Zimmerman said. 鈥淚t’s a wonderful material. From performance standpoint, the material is exceptional.鈥�

Such materials are more commonly found in Japan, according to Zimmerman.

鈥淚n Japan, people will pay more to live in a building that is built to survive an earthquake,鈥� he said. 鈥淵ou don’t see that in the U.S.鈥�

In Portland, more than 90 percent of new construction uses conventional force-resisting systems that include concrete or plywood shear walls as well as steel brace frames. The idea is to dissipate forces.

Owners looking to better their buildings’ chances of surviving a quake with minimal damage typically use one of three methods.

Seismic base isolation is considered the gold standard. A building is set on a series of isolators, which move during a quake while the building stays in place. The Pioneer Courthouse in downtown Portland was retrofitted using this method.

鈥淵ou can get 100 percent reduction (in forces),鈥� Zimmerman said. 鈥淚t has limitations in terms of height. It’s also the most expensive method.鈥�

A more economical option is the use of fluid viscous dampers. During a quake, fluid is pushed through an opening, producing a damping pressure to dissipate forces. The system operates like a car’s shock absorbers. While the blow is softened, the building still feels the jolt. The Multnomah County Central Courthouse was retrofitted using this method.

鈥淲hen we design using fluid viscous dampers, the target is for how much shock we want to reduce,鈥� Zimmerman said. 鈥淲e can get a very dramatic reduction of say 40 to 50 percent.鈥�

However, money plays a big role in the amount of shock reduction. Systems that produce the largest reduction are too expensive for many buildings; more affordable ones tend to reduce shaking by approximately 30 percent.

Another system finding a growing audience is the rocking and re-centering system. Instead of resisting an earthquake’s forces, the walls lift up in a controlled manner to dissipate energy. Rocking systems are being employed for Oregon State University’s Peavy Hall and the Framework tower in Portland.

These modern systems will likely be considered for many future projects in Portland, which has nearly 1,500 unreinforced masonry buildings not retrofitted. Those buildings have walls and structural elements made of brick, cinder block, tiles, adobe or other masonry聽material without reinforcing materials like rebar.

鈥淩ight now each of the buildings is unique,鈥� said Carmen Merlo, director of the Portland Bureau of Emergency Management. 鈥淪ome are vacant, some require more strengthening than others. Each building owner is going to have a different experience.鈥�

The city is developing a mandatory retrofit policy that will be presented to the City Council in late summer or early fall. Under the proposed policy, owners would have up to 30 years to completely retrofit their at-risk buildings, providing that certain intermediary goals are met.

鈥淭he fact we are requiring the intermediate steps would mitigate the worst of effects,鈥� Merlo said. 鈥淲e are working to address worst life/safety risks first.鈥�

Most of these buildings were built long before Northwest seismic risks were identified.

鈥淣o one knew about the high earthquake dangers until the 1990s,鈥� said Walter McMonies, a Lane Powell attorney who owns two at-risk buildings in Portland. 鈥淯nfortunately it will cost an arm and a leg to fix it. Owners like myself will spend a lot of money on this.鈥�

Costs to retrofit buildings throughout Portland will surpass $1 billion, according to city estimates.

A retrofit of McMonies’ 46,000-square-foot, 36-unit Trinity Place Apartments will cost between $1.3 million and $1.5 million. The cost could have been far higher. The city’s estimate was $2.5 million, he said, but the building’s flooring didn’t need as much work as anticipated.

鈥淥ur floor diaphragm is double-reinforced,鈥� he said. 鈥淭he floor was very strong.鈥�

The biggest portion of the job was strengthening the walls. Center core drilling, the process McMonies settled on, often is used for historic structures. Holes are drilled from the tops of walls into the basement. The holes are then filled with reinforced rebar and concrete to prevent a collapse in an earthquake.

鈥淢aybe not so much for San Francisco, but it’s a cutting-edge process for Portland,鈥� he said.

The team also had to install steel braces to keep the walls in place. Then each unit had to have the walls’ attachment to the ceiling strengthened to keep the walls from peeling away when shaken. Also, flooring was attached to the walls.

鈥淲e went in every four feet and bolted floor joists to the walls,鈥� he said. 鈥淚f the joists pull away from the wall, you have a pancaking effect.鈥�

The total process has taken more than four years and will stretch into at least a fifth.

Despite scientific advances, no quick or cheap seismic solutions exist, Zimmerman said.

鈥淚 actually think the future of seismic design is focused on pairing the systems we know about,鈥� he said. 鈥淭he key is pairing the right system to the individual building.鈥�