Faculty, Structural Engineering
Shock wave dynamics, shock, polymers, high strain rate loading.
Shock Wave Dynamics
The area of shock dynamics, and in particular shock focusing, has been of high interest since the 1950's. Fast forward to 2016, and we realize that many questions related to shock dynamics remain unanswered. Eliasson’s research group's work on shock dynamics can be divided into two parts: (1) how to use multiple shock fronts to create more extreme conditions (at a specified target area) than if a single shock front was used, and (2) how to mitigate shock waves passively using cheap, reliable and environmentally friendly methods utilizing techniques learned from shock focusing studies.
Dynamic Response of Polymers to High Strain Rate Loading
Of particular interest is understanding properties of wave propagation in fluids in contact with solid structures. The response of the structure depends to a large degree on what type of fluid it is in contact with during the impact. For example, the response of dynamic events taking place in ideal laboratory conditions with room temperature and standard atmospheric pressure is very different from for example dynamic events taking place in environments with varying relative humidity at high or low temperatures.
Shocks & Impact on Complex Materials
Eliasson’s research extends to areas that concern different types of materials such as amorphous metals and biological materials. While seemingly diverse, these areas have much in common with the core expertise of her research group. Traumatic brain injuries (TBIs) and mild TBIs are common among soldiers returned from war, athletes in contact sports and people injured in falls or transportation accidents. The most alarming fact is that the long-term effects of repeated concussions remain unknown. Consequently, Eliasson and her colleagues proceeded to develop an experimental methodology where one has full control of the rapid applied mechanical loading, and can simultaneously study the mechanical and biological response of "brain-in-a-dish" models to quantify injury.
Eliasson’s project on amorphous metals has proven useful to study impact loading at low speeds, and shock loading at very high speeds (700—1500 m/s). This effort has helped her group to establish elastic limits and a Hugoniot curve for two types of iron-based amorphous metals - resulting in Hugoniot elastic limits never before seen for these types of materials.
Before joining UC San Diego in 2016, Eliasson was an associate professor in aerospace and mechanical engineering at the University of Southern California. Before joining USC in 2009, she was a postdoctoral scholar at the California Institute of Technology. She holds a Ph.D. in mechanics from the Royal Institute of Technology in Stockholm, Sweden. She has won the Hanna Reisler Mentorship Award in April 2015.