Engineering’s Vallejo helped mentor many international students

Luis Vallejo, a 37-year professor of civil and environmental engineering known for bringing students to Pitt’s Swanson School of Engineering from his native Colombia, mentoring students from all over the world and helping them gain a career, died March 18, 2022.

“He changed my life,” said Sebastian Lobo-Guerrero, who was a student at the end of his bachelor’s degree program at the Universidad de los Andes in Bogotá when Vallejo was invited to teach there. Vallejo chose Lobo-Guerrero to participate in a National Science Foundation grant back at Pitt.

“I had no clue about where Pittsburgh was in the world,” Lobo-Guerrero recalled. But two weeks later — after Vallejo convinced Lobo-Guerrero’s professors that he could finish his bachelor’s degree 2,500 miles away — Lobo-Guerrero was here: “He gave me all those chances and I ended up doing both my master’s and Ph.D. under him. We ended up publishing 18 to 20 papers together. He had adopted me to his family.”

Vallejo eventually helped Lobo-Guerrero join the engineering company where he has worked for the past 16 years, which led to the presidency of the city’s geotechnical engineering society.

“He really helped a lot of people from Colombia to find a way into Pitt,” Lobo-Guerrero said. “He influenced an entire generation of geotechnical engineers in Pittsburgh today. Everyone is always appreciative, not only for his technical content, but for the personal connection. That’s what made him so unique.”

Through the years, Lobo-Guerrero recalled, “He was always asking about every student that he had. He helped me a lot to recruit people for the company that I work for. It just shows the kind of person he was. … If anything I have to remember from his life, it was the service he was doing to others. We literally traveled the world when I was at Pitt — he was always encouraging students to get involved” with conferences and other scientific meetings.

“When you come to this country as an outsider,” he continued, “you are very happy about the opportunity you have … but you don’t always understand about the culture. Before diversity and inclusion was a thing, he was already a king of that,” helping students from Nigeria, Malaysia, Japan and elsewhere to acculturate.

Vallejo earned his civil engineering degrees from Washington State University (BS, 1982), Michigan State University (MS, 1984) and the University of Wisconsin (Ph.D., 1977). Joining the University faculty in 1983 as assistant professor, he retired as emeritus professor in 2018.

He was a nationally recognized expert in geotechnical engineering with expertise in slope stability and the application of fracture mechanics and fractal theory in soil mechanics. He published numerous journal papers, several books, 34 technical publications in book format and 123 refereed conference proceedings.  He taught more than half a dozen different courses here, mentored 12 PhD and 30 master’s students, and was a member of the editorial board of the international journals “Engineering Geology” and “Geomechanics and Engineering” and associate editor of the American Society of Civil Engineers’ “Journal of Geotechnical and Geo-environmental Engineering.”

He received the Morada al Sur award from the State of Nariño, Colombia, for contributions to education and technology; the award for superior performance from the Office of Surface Mining, U.S. Department of the Interior; and the Lilly Endowment teaching fellowship for excellence in teaching.

He served on the University Senate at Pitt, the annual promotion and tenure review committee in the Swanson School and as undergraduate coordinator in his department

N. Catherine Bazán-Arias, another one of Vallejo’s students, called Vallejo one of “the gurus of geotechnical engineering during my years at Pitt,” who “taught me the importance of looking beyond what is visible to understand the dynamics behind soil-structure interaction (where) so many critical parameters lie hidden from sight.”

After finishing her undergraduate degree in structural engineering here in 1992, Bazán-Arias was convinced by Vallejo and a few of his colleagues to remain here for graduate school. She was from Mexico, and it was important that she and Vallejo shared a language and “cultural resonance,” she said: “Being a Latina in engineering was relatively unique in the United States and also in geotechnical engineering. His technical expertise and his willingness to share his knowledge … finally provided me the path to focus my structural background.”

He also helped her learn to deal with setbacks, such as a graduate test in which a machine malfunctioned. “I learned that day that panicking is not a really good option and a mentor who can coach a mentee through the experience is the best. To provide me the confidence and the calmness to address complexities in a highly complex field is what I remember most.”

Radisav Vidic, Vallejo’s department chair, recalled his colleague as someone “who cared about students a lot. He was very willing to go out of his way accommodating students.”

He was also, Vidic said, “a top notch expert. He made significant contributions to this profession … He was a real gentleman and a thoughtful person who considered the well-being of the department, and he was dedicated to our students to help them master the topics he was passionate about.”

— Marty Levine