After the 1925 earthquake devastated Santa Barbara and a portion of State Street, the survivors were left with the decision of how to rebuild and how to do it more safely.
One of the most well-known effects of the disaster was the decision to rebuild much of downtown with the city’s signature design style — Spanish Colonial Revival. The move helped create Santa Barbara’s image as the tourist destination it is today.
The city began requiring — and still requires — builders in certain parts of the city to adopt the Spanish style.
However, along with a new style, the survivors also had to learn how to make safer buildings.
According to Sage Shingle, a structural engineer for T&S Structural, the 1925 disaster was one of the first earthquakes to be studied by engineers who wanted to see why buildings failed.
“It was really the kick-starter. You know, there were obviously earthquakes before, but it was really the kick-start of, ‘We need to design for seismic forces,’” Shingle said.
Shingle shared his knowledge and experience during a meeting at the Architectural Foundation of Santa Barbara Gallery on Thursday, where he explained the causes of earthquakes, the aftermath of the 1925 earthquake, and how buildings have changed to withstand them.
Engineers at the time traveled to Santa Barbara to understand how the earthquake affected buildings. A report was made analyzing the buildings and how they were designed.
“Our inspection of damaged buildings leads us to the conclusion that much of the damage might have been avoided if better material and workmanship had entered into the construction of the buildings affected by the earthquake. Wherever good materials have been properly used, and the design has been an intelligent one, slight damage or none has resulted,” Shingle quoted from the report.
The report went on to note that buildings that used brick, tile or concrete did not hold up well.
Santa Barbara architect Jeff Shelton said the other issue with the structures was the weight. He explained that even buildings that had some steel reinforcement were not strong enough to fully withstand the force.
“If you look at the old photos, you have heavy buildings flopping around in an earthquake, and what you see, all the walls are down, they’re all piles of bricks. So that was a recipe for disaster anywhere in the zone four, which was the heaviest earthquake zone,” Shelton said.
The first mandatory building code was enacted 10 years after the 1925 earthquake and two years after the 1933 Long Beach earthquake, and was five pages long.
Other major changes involved rules for building schools and hospitals. Schools, for example, cannot be made without reinforced masonry.
Additionally, hospitals, police stations, fire departments and other emergency operations centers are required to be habitable after an earthquake, which means they have to be designed to be stronger and withstand natural disasters.
In 1925, many of the buildings damaged by the earthquake were completely torn down and rebuilt from scratch. Some were rebuilt with wood since it was better able to handle seismic forces.
Some buildings, such as the Santa Barbara Mission, were repaired and reinforced. The repairs to the Mission, however, began to fail by the 1950s. The building was then repaired again with concrete.
By the 1990s, the State of California passed a mandate that masonry buildings were required to be reinforced. It meant that some of Santa Barbara’s buildings had to be retrofitted to meet the state’s standards.
According to Shingle, among the biggest differences in designing buildings today are the materials used.
One example is the use of plywood, which uses nails to attach to the frame. Shingle explained that nails help absorb and disperse some of the earthquake’s energy by shaking, offering better protection for the building.
