Civil Engineering Assistant Professor Michelle Bernhardt-Barry still remembers her 8th birthday party. The cake featured construction equipment moving mounds of dirt, which she says should have been a clue to her parents about what was to come. Now, more than two decades later, Bernhardt-Barry has won one of the most prestigious awards given by the National Science Foundation to pursue her research into soil mechanics.

The Faculty Early Career Development Program is the most prestigious NSF award given to junior faculty members who show outstanding promise in both teaching and research, according to the organization. The award amount is approximately $500,000.

Bernhardt-Barry’s research focuses on improving the use of soil as a building material, which has applications locally, globally and someday, perhaps, beyond Earth.

"Nature does a lot of things really, really well."

'What makes buildings stand up'

Looking back, Bernhardt-Barry can see the clues she was destined for a career in engineering.

“I always had a knack for drawing houses, I was always building things, playing with Legos, the typical engineer story, I guess,” Bernhardt-Barry said. “I was also very interested in Roman architecture and was amazed by many of the ancient buildings across Europe.” As she started considering a career path, Bernhardt-Barry realized she was more interested in how such massive structures could be built to stand the test of time, versus how their architectural features were designed.

That led to her undergraduate studies in civil engineering at Texas A&M University, where she would later complete a master’s and doctoral degree.

Bernhardt-Barry started her undergraduate degree with a focus on structural engineering. “At first, I wanted to design skyscrapers,” Bernhardt-Barry said. “But I had a senior capstone project to design an 11-story building. After four stories, I was bored and couldn’t imagine designing a 100-story building. I realized I didn’t want to do that for a career. I was more interested in finding out what makes things stand up, and what happens below the ground surface, versus how they’re designed vertically.”

Bernhardt-Barry realized the short answer to that question is: soil, and that soil is “a fascinating and complex material.” The soil underneath a structure plays a critical role in the construction process, and recent advances in technology have opened new avenues of soil use.

Imitating nature

Bernhardt-Barry’s 2018 CAREER award research focuses on biomimicry, leveraging patterns found in nature to produce materials that are as strong as possible, while using as few resources as possible.

“Nature does a lot of things really, really well,” Bernhardt-Barry said. Shapes like honeycombs and nacre (also known as mother of pearl) can be orders of magnitude stronger and tougher than their constituent parts.

But gathering ideal soils for use in construction isn’t always practical, and replacing poor soil can be costly and time consuming. Thanks to recent technological advances, engineers can now create certain types of soil structures, and perhaps one day even make soil stronger using 3D printing.

Called “bio-inspired design,” Bernhardt-Barry said learning about mechanisms found in nature that enable loads to be carried efficiently and incorporating them into soils opens new possibilities for building roads, foundations and structures. Engineers can make better use of the native soil at a site by 3D printing soils into cellular patterns or shapes like the honeycomb. But first, those 3D-printed soils need to be understood.

The benefits of bio-inspired design have been studied for materials like metals and composites, but the body of research lacks such information about brittle, particulate materials such as soils, Bernhardt-Barry said.

And the results could be out of this world.

"I don’t know that anyone since ancient times has stopped to ask ‘can we do more with soil?’"

Implications around the world and beyond

Some of the implications of Bernhardt-Barry’s research are easy to see. Improving the nation’s infrastructure by building stronger, more efficient structures means less material and maintenance costs, saving money for businesses and governments.

“You hear it a lot – our infrastructure is crumbling,” Bernhardt-Barry said. “When you look at the materials used and how we build things, there’s always this question of ‘can we do better with what we’ve got?’

“I don’t know that anyone since ancient times has stopped to ask ‘can we do more with soil?’”

Some of the greatest potential benefits of Bernhardt-Barry’s research are in developing countries.

In many developing countries, the terrain lacks the components to make aggregates and concrete in large quantities, or it’s difficult to navigate construction equipment through undeveloped areas. If engineers could find a way to use existing soil as a building material in those areas, it could unlock new potential, Bernhardt-Barry said.

That need is often acutely felt after a natural disaster or a conflict, when huge stretches of roads and buildings are destroyed at once, she said. The ability to provide rapidly-constructed, sturdy housing, roads and hospitals in those areas would be a significant advantage to relief efforts and would speed the recovery process for those communities.

But the possibilities extend even farther.

As governments and businesses focus on space travel, the desire to build structures on the moon or Mars will bring considerable engineering challenges, not the least of which is how to construct a building in space without transporting tons of concrete, Bernhardt-Barry said.

Being able to use lunar or Martian soil as a building material would solve that problem, though Bernhardt-Barry cautions the research isn’t yet that advanced. However, she’s optimistic the answers lie within nature itself.

“This work is in the early stages, and it sounds a bit like science fiction, but through this type of research we see that nature has figured out ways to maximize strength with minimal material and energy,” Bernhardt-Barry said. “And there’s a lot more we can still learn from nature.”

Reaching out

Like all National Science Foundation CAREER awards, Bernhardt-Barry’s project includes funding for science education. Bernhardt-Barry’s outreach has two components: teaching students to work on trans-disciplinary teams and improving diversity in science.

“The ‘grand challenges’ presented by many of the national engineering academies require large, interdisciplinary teams to solve,” Bernhardt-Barry said.

That’s why her plan includes a course open to students in science, technology, engineering, the arts and math.

“The idea is to give them a design challenge and then let them create a framework and a shared language for how to approach and solve that problem,” Bernhardt-Barry said. “It’s designed to get them used to working in that type of transdisciplinary environment.”

The program will be a 10-day intersession course for undergraduates, and will be folded into an existing course on numerical modeling for the graduate-level curriculum. A similar type of module will also hopefully be implemented in a graduate course in the Fay Jones School of Architecture and Design, Bernhardt-Barry said.

Another aspect of Bernhardt-Barry’s outreach centers on increasing the diversity of engineering students. Even as the U.S. science and engineering workforce becomes more diverse, females and minorities continue to be underrepresented.

Bernhardt-Barry’s outreach for female students focuses on two programs: GirlTREC for 5th and 6th graders and Engineering Girls Camp for 7th and 8th graders, both hosted by the University of Arkansas College of Engineering.

Bernhardt-Barry also plans to develop a two-day short course aimed at providing targeted spatial skills for diverse students ranging from 6th grade to the undergraduate level. Research has shown spatial reasoning is a key predictor of success in STEM fields.

Bernhardt-Barry said she also plans to continue recruiting diverse undergraduate and graduate student researchers, in particular supporting one student from the Engineering Career Awareness Program annually. The Engineering Career Awareness program is an initiative of the College of Engineering aimed at recruiting, retaining and graduating underrepresented students for whom finances could be a barrier to success.

A career milestone

For Bernhardt-Barry, receiving one of the National Science Foundation’s most prestigious awards was a remarkable milestone in her career.

“It’s extremely exciting,” she said. “You work a long time for something like this, you spend so many hours on these proposals. To think one of your ideas has been evaluated by your peers and deemed worthy of this kind of funding, that’s a great feeling.”