Grad Student Recognized for Research’s Public Impact
Civil engineering doctoral candidate Riccardo Cappa has been named a 2015 UC Irvine Public Impact Distinguished Fellow by the university’s Graduate Division. Cappa, who studies earthquake-related hazards and disasters, is one of only three graduate students to receive the prestigious $10,000 award.
The Public Impact Fellowship supports doctoral students whose research has the potential to significantly improve or enrich local, national or global communities. In addition to the prospective impact of their work, the three recipients were selected on the basis of their presentations, interviews, academic records, letters of recommendation, and their ability to convey the research succinctly to a broad audience.
Cappa uses numerical simulations and centrifuge models to characterize the seismic response of water-diverting structures like levees and dams. In particular, he is studying levees on the Sacramento-San Joaquin River Delta. These structures, made of loose dredged sands, are built on a foundation of peat – organic matter that is highly compressible and easily erodible. After 150 years of land reclamation and farming, the inland of the majority of Delta islands and tracts currently lie up to five meters below sea level.
As a consequence, a single breach in these fragile levees would easily result in the flooding of an entire island, causing considerable economic damage. A severe earthquake striking the region could cause multiple simultaneous breaches, resulting in a catastrophic scenario.
The volume of water that would rush into the Delta islands could cause salt water from San Francisco Bay to draw back into the Delta, Cappa says, causing devastation. This mix of fresh and sea water would disrupt the region’s delicate ecological environment and derail the half-billion-dollar-per-year agricultural industry. But even more importantly, saltwater invading the Delta, which is home to the state’s water delivery system hub, would require a total shutdown for of the system for more than 18 months. Twenty-five million California residents would be affected, with regions like Southern California losing more than 30 percent of the water it receives daily from the Delta.
“If you have to explain this whole process to a legislator, it’s not easy,” says Cappa, who collaborates with graduate researchers at UCLA as well as here at UCI. “Our objective is to demonstrate the potential for a catastrophic scenario. If an earthquake strikes the region, many islands [in the Delta] will fail at the same time.”
Cappa utilizes a giant NASA-donated centrifuge with a 30-foot diameter, located in Davis, Calif., to simulate the response of model levees to earthquakes of different magnitudes. He studies both the seismic behavior of the peaty foundation soil, which can increase demands on the levee fills, and the performance of the levees themselves during an earthquake.
“I did this centrifuge experiment/simulation to prove the risk,” he says. “The current knowledge of the seismic response of these levee structures is very limited.”
“Centrifuge simulations of this kind are challenging given the unique material behavior and complex failure mechanisms implemented in the model and in the in-situ system itself,” says Cappa’s advisor, UCI civil and environmental engineer Anne Lemnitzer. “This project is highly extraordinary to have such a strong component of broader impacts along with the intellectual merit of this study.”
Lemnitzer is pleased with Cappa’s progress. “Riccardo mastered the challenges of complicated experimental research well and has proved himself an aspiring young researcher who will significantly contribute to the advancement of knowledge in our field.”
Cappa, who expects to complete his doctorate this year, has a bachelor’s degree in architectural and building engineering, and a master’s in structural engineering. He already has gained public recognition of his research, presenting it to the Association of State Dam Officials, the American Society of Civil Engineers and the California Geotechnical Engineering Association. He has several papers under review and published his work in last year’s Dam Safety National Conference publication.
An active member of the Earthquake Engineering Research Institute, the Geotechnical Graduate Student Society, the California Geotechnical Engineering Association and the American Society of Civil Engineers, Cappa says he is thrilled to be selected a Public Impact Distinguished Fellow. “This fellowship is an incredibly motivating acknowledgment for young students,” he said. “I am very proud and thankful for the valuable support UCI provides to Anteaters every year.”
Cappa was also chosen by UCI Graduate Dean Frances Leslie to attend a student workshop in Washington D.C., in April, organized by the American Association for the Advancement of Science. Participants in the Catalyzing Advocacy in Science and Engineering workshop will spend three days learning about Congress, the federal budget process and effective science communication, and will meet with members of Congress or congressional staff.
In addition, Cappa, last year’s Dr. Medhat Haroun Fellowship award winner, is one of two UCI students selected to present his research to UC President Janet Napolitano in Sacramento on April 28 at UC Graduate Research Advocacy Day.
“UCI is really helpful in that it not only provides financial support but also provides me with the opportunity to travel and disseminate my research findings,” he says gratefully.
“And hopefully we’ll make our case and I’ll be able to express [the problem] to legislators and raise awareness as well as the need for more funded projects like this. Californians live without even knowing that if an earthquake happens in the Delta region the consequences are devastating.”
The Public Impact Fellowship program also selected 11 graduate students for honorable mention awards of $1,000 each. Three engineering students were among the recipients. They are:
- Janahan Arulmoli, a biomedical engineering doctoral candidate, who studies biomaterial matrices for neural stem cell transplants as a way to treat central nervous system disorders;
- Jiawen Li, a biomedical engineering graduate student, who researches and builds miniature integrated intravascular ultrasound optical coherence tomography systems for identifying high-risk heart attack patients; and
- Sophia Lin, a chemical engineering and materials science doctoral candidate who studies silica structures for enhanced fluorescence detection with applications in point-of-care diagnostics.
-Anna Lynn Spitzer