An international focus on earthquake assessment and preparedness has resurfaced in the aftermath of Haiti’s recent disaster and two recent California quakes.
Dr. Robb Moss, a at Cal Poly assistant professor in soil mechanics and earthquake engineering, is part of Geo-engineering Extreme Events Reconnaissance (GEER), an association of seismologists and geologists devoted to gathering scientific data to improve methods to prevent greater damage and deaths from earthquakes.
“As engineers, we prepare for the next one,” Moss said. “We focus on what we can do better next time. If we know details, we can build on those to increase mitigation in the future.”
GEER asked Moss to join a reconnaissance team that would gather geotechnical data in Haiti.
“Some earthquakes are fun scientifically, but in the situation with Haiti, science becomes hard when you want to help,” Moss said.
Scientists forecast that there is more than a 99 percent chance that an earthquake of magnitude 6.7 or larger will hit California in the next 30 years. Dr. John Jasbinsek, a Cal Poly physics instructor, said San Luis Obispo sits just 150 km west of the San Andreas Fault, a system similar to the Enriquillo-Plantain Garden fault zone that runs just South of Port-au-Prince, Haiti.
“The Haiti earthquake was a left lateral strike slip fault, the same type of fault as the San Andreas fault but it moves to the right instead,” Jasbinsek said. “The way they move is similar, but the San Andreas Fault is bigger.”
With the death toll rising potentially to 200,000, Haiti’s capital city remains in ruins and in desperate need of aid and ranks close behind the 1976 Tangshan, China earthquake as one of the deadliest quakes ever recorded.
Fault system assessment can provide probabilities, but predicting earthquakes to the hour, day or month has rarely been successful. Scientists predicted that the Loma Prieta area would experience an earthquake due to a seismic gap in the San Andreas Fault. They had been mapping since 1968, but the predictions were not enough to prepare for a 6.9 magnitude quake that hit the San Francisco Bay Area on Oct. 17, 1989. Known as the World Series Earthquake, 63 people died after 10-15 seconds of trembling.
Michelle Smith, an earth science senior and earthquake enthusiast, is fascinated by the idea of inducing earthquakes. Like Moss, she is torn between the marvels of Earth’s systems and the damage they cause. She elaborated on the Haiti earthquake by discussing the major lack of earthquake codes.
“Getting under a doorway works for us, there … it doesn’t,” Smith said.
A mixture of poor infrastructure with a massive earthquake is the worst of two worlds. According to Moss, the damage in Haiti is almost worse than what would have happened in a developing country where there is limited infrastructure. The economy in Haiti had enough money to build, but the structures were built incorrectly. With an almost totally unreinforced masonry building style, the damage was unavoidable, he said.
“It’s all about building structures so that people can survive,” Moss said.
Closer to home, on Dec. 23, 2003, the San Simeon earthquake with a magnitude 6.5 hit the Central Coast, causing most of the damage in Paso Robles. Only two deaths occurred due to the collapse of a two-story unreinforced masonry building.
Twenty-year-old Jennifer Myrick was one of the victims of the San Simeon earthquake. After their daughter’s death, Vicky and Leroy Myrick spent nearly a year battling with the law to get warnings placed on similar buildings around the state. From their efforts came the Jennifer Lynn Myrick Memorial Law, in which owners of roughly 25,000 old brick buildings in heavy earthquake zones around most of California who fail to post a placard notifying the public of the building’s unsafe status would be fined.
According to Moss, there are many similar buildings with placards in downtown San Luis Obispo, which Moss considers to be the worst town in California for structures that need to be retrofitted.
Mark Ellery, part of the city’s Architectural Review Commission, said the final deadline for all buildings to make necessary retrofits is 2012.
“After the earthquake in Paso Robles in 2003, the city of San Luis Obispo recognized buildings as part of an importance factor where they priority listed each structure according to how much of a danger they present,” Ellery said. “The city has offered a lot of incentives including granting no fee permits to make tenant improvements on top of the retrofits.”
The Cal Poly campus was surveyed two years ago by an independent structural engineering firm along with members of the CSU Seismic Review Board. After inspecting for code compliance and compliance with established CSU standards, their results showed that Cal Poly’s environment meets code.
“We have a relatively new campus compared to some of the UCs,” Moss said. “It’s up to code and relatively modern.”
The Cal Poly Web site provides a campus emergency management plan for earthquakes. Safety guidelines include staying away from glass windows, shelves or heavy equipment and taking cover under a desk or chair. Evacuating only after the tremors have ceased is advised.
Dr. Gregory Bohr, a Cal Poly geography professor, emphasizes the importance of having bookshelves bolted to the walls and heavy objects not stored where they can fall on people.
“It’s not a bad idea to have emergency supplies (food, water, or first aid kit) available and refreshed from time to time,” Bohr said.
There are several modes of communication to get information out to students and faculty. E2 campus is a software program where, once you register your phone, notifications will be sent directly to you during an emergency. There are roughly 3,000-4,000 students registered for this system, about one-fifth of the student body.
An emergency notification broadcast system will be going in next month, in which speakers on campus phones will act as warning systems, said Mark Hunter, head of facilities at Cal Poly. There are also exterior speakers on campus buildings including the clock tower and the administration building. There are radio stations for emergency information distribution as well (920 AM, 1400 AM, and 98.1 FM).
“We have a pretty good system for getting the word out, and older and weaker buildings have been strengthened,” Hunter said.
The only problem with all this technology is that in the case of an earthquake, an announcement over an intercom or a text message will be too late.
“The thing about being prepared, you can flip the switch or send the mass text message, but that’s not going to happen until after the fact,” Moss said.
The newest technology for earthquake preparation, an Early Warning System (EWS), tells you how big and how fast an earthquake is. The technology is stationed at a fault that is prone to slip, essentially a hot spot for earthquakes. Once the earthquake hits, the light waves will travel faster than the sound waves, meaning news will get to us faster than the earthquake, but only by seconds or minutes. In this way, a PA system alerts when the earthquake will hit. Jasbinsek is excited about the prospective benefits of the Early Warning System.
“It would give people not only enough time to get to a safe place, but a brain or a heart surgeon could pull out of surgery, valves to water pipes could be turned off, aqueducts or heavy machinery could be shut down, among other things,” Jasbinsek said.
At the moment, Japan, Mexico and Italy all have functioning EWS. California is dabbling with the idea, but the systems have yet to be implemented.
Vic Crosariol, a graduate student at Cal Poly, has spent the past three years working on a research project involving subway systems responding to scale model testing. He is using a shake table, a piece of equipment that mimics earthquakes. Built 10 years ago with equipment loaned from UC Berkely, the shake table has seen many modifications.
“We are piggy-backing on previous work,” Crosariol said. “There’s not much research in this type of soil structure interaction, so we are trying to fill the gaps in research to make more accurate designs for the future. Seismic provisions are getting really good in the United States. We are making a lot of good strides preventing any real catastrophes. It’s not something you can stop. (Earthquakes) are going to happen, we are just trying to prevent further damage.”