Center for Innovation Webinar Touches on Importance of Seismic Design in West Coast Cities

By Catherine Sweeney 

In February of this year, a major earthquake devastated communities throughout Southern Turkey and Northern Syria. Now, those in the architecture, engineering and construction industry are looking at the catastrophic event for information about how to better prepare their communities in wake of potential disaster. 

To share ideas about seismic design, the Center for Innovation recently held a webinar, titled “Lessons from the 2023 Turkey Earthquake and what it Means for California.” The webinar consisted of a three-person panel including Jennifer Gross, associate principal at Degenkolb Engineers; Adam Hugo-Holman, principal at Degenkolb Engineers and Baris Lostuvali, project executive at The Boldt Company. During the webinar, the panel discussed various topics related to building performance, community resilience, critical infrastructure and more. While largely discussing the implications for the San Francisco Bay Area, the outcome shows greater implications for the larger West Coast region as well as the importance of seismic design in general. 

“Obviously, we are expecting our big one sometime on the horizon,” said Lostuvali. “And how do we get ready for that risk? And, and in response, what can we do as an AEC community to better get ready and prepare for it?”

With a magnitude of 7.8, the recent earthquake in Turkey, known as the Kahramanmaras Earthquake affected millions of people as well as the buildings they occupy. During the Turkey Earthquake, the death toll totaled more than 50,000. Cities also saw a combined damage of more than $34 billion worth of damage to various buildings throughout the region.

Home to several major fault lines, including the San Andreas and Hayward, the West Coast could face significant amounts of damage in the event of a large earthquake, said Hugo-Holman.  

“You are talking $60 billion worth of loss, deaths of 2,500 people and lots and lots of buildings are heavily damaged, and similarly, on the Hayward fault, both are real risks to our communities. Turkey, and in the United States, and California, especially, have a shared history of earthquake damage,” he said.

To help with these risks, the panelists suggested that the AEC community needs to work together to care for older buildings and design new buildings for safety and repairability. When taking into account building damage during the Kahramanmaras earthquake, the panel noticed that some buildings held up while others were a total loss. Of these, residential buildings seemed to fare worse, while government buildings, schools and other similar structures performed better. 

This is likely due to the types of construction in these buildings. For instance, soft story buildings – structures which have a weaker first floor – are unable to carry the weight of their upper stories. Another type of construction found faulty in these events are unreinforced masonry buildings. According to Degenkolb Engineers, even a minor earthquake can cause damage or collapse to an unreinforced masonry building with repairs being a long, costly process. 

Information from Degenkolb shows that during the 2001 Magnitude 6.8 Nisqually Earthquake in Washington, the most common forms of damage came from these types of buildings, including fallen bricks, cracked walls and more. Even during the 1989 Magnitude 7.1 Loma Prieta Earthquake in Northern California, when the earthquake was centered far away, these types of buildings still received some damage with about 16 percent being severe enough to require them to be vacated. 

“I think during the pandemic we sort of reevaluated what the word essential workers were and I think we need to think about what that means for our buildings as well. I think we need to reevaluate what is essential,” Hugo-Holman said. “We spent a lot of time and money and it’s been well spent on protecting our schools and hospitals. And in this earthquake in Turkey, we saw those buildings often performed very well, but they were often surrounded by a community that was completely devastated.”