A leader in the field of structural engineering whose studies were applied to the San Francisco Bay Bridge, the trans-Alaska Pipeline, the San Francisco Museum of Modern Art and numerous other projects, Popov authored engineering textbooks that became academic classics around the world. He was active in research and lecturing both nationally and internationally up until his death.

Many colleagues and former students, some of whom became renowned leaders in their own right, credit Popov with pioneering the study of inelastic behavior and seismic response of reinforced concrete and steel buildings and with providing invaluable encouragement early in their own engineering careers.

"He was a real giant among us," said professor emeritus Karl S. Pister, former dean of UC Berkeley's College of Engineering and former chancellor of UC Santa Cruz. "I met Egor when I was a graduate student in 1946. His courses and his counsel inspired me to go on for my PhD. When I returned to Cal as a young assistant professor, I co-taught courses with him, and he became my mentor. In short, I really owe my career as an academic to Egor."

Popov was born in Kiev, Russia, in 1913. He and his family escaped to Manchuria during the Bolshevik Revolution and eventually sailed to America. After earning his bachelor's degree with honors in UC Berkeley's civil engineering program in 1933, Popov completed a master's degree in the same field at MIT in 1934, and his doctorate in civil engineering and applied mechanics from Stanford University in 1946.

After joining the UC Berkeley faculty in 1946, Popov introduced graduate mechanics courses into the civil engineering curriculum and was largely responsible for creating a division of structural engineering and structural mechanics within the civil engineering department. He served as the division's first chair and directed the Structural Engineering Laboratories.

Although Popov retired in 1983, since 1996 he has held the title of "Professor in the Graduate School," an honorary title held by a select number of retired UC Berkeley faculty members still active in research on campus. This honor not only is a title, but includes research support.

Popov's research had strong theoretical and experimental underpinnings, yet was applied broadly in the professional practice of structural engineering. His early analysis of structural shells led to advances in the design and construction of water storage tanks and airplane hangars. His work helped the National Aeronautics and Space Administration solve buckling problems at its huge environmental chamber in Houston and was instrumental in establishing buckling criteria for the trans-Alaska pipeline.

Much of his subsequent research focused on the seismic response of both reinforced concrete and steel structures, which is critical for creating buildings suitable for seismically active regions as well as for the design of offshore oil platforms. Popov and his UC Berkeley colleagues had particular success in recent years with clarifying how to improve the seismic behavior of steel buildings using new ways of connecting beams and columns by welding, high-strength bolts, and diagonal bracing.

"If we removed Egor Popov's contributions from the seismic design of steel structures, we would lose most innovations of the last 30 years," said UC Berkeley civil engineering professor Filip Filippou, a former student of Popov's who joined the faculty in 1983. "He was a trailblazer, laying out the groundwork that others, many of them his students, followed. His devotion to teaching and to his students is unequalled. One had the sense of belonging to an international family with him, his students, colleagues, and friends."

Popov's many awards included election to the National Academy of Engineering in 1976, the campus's Distinguished Teaching Award in 1977, the ASCE Normal Medal in 1987, the Berkeley Citation in 1983, a Distinguished Engineering Alumnus Award from Berkeley in 1985, and the Earthquake Engineering Research Institute's Housner Medal in 1999. In 1977, Popov's colleagues, in cooperation with the National Science Foundation, organized a UC Berkeley conference in honor of his 30 years of teaching.

Popov authored and co-authored more than 300 technical papers and numerous textbooks, including the landmark textbook "Mechanics of Materials," first published in 1952, with a second edition in 1976. His most recent book was "Engineering Mechanics of Solids," published in 1990. Popov's books have been translated into numerous languages and are used at top engineering schools around the world.

Popov will be best remembered for "his tenacity, his brilliance, and his ability to motivate his students," according to Stephen Mahin, another former Popov student, who joined the UC Berkeley faculty in 1977. "It's by his example that all his students have carried on the research. He exemplifies the spirit of Berkeley - not only doing great work, but also delivering to the world great students who can continue the tradition of advancing the research."

Popov is survived by a brother, Nicholas Popov of Santa Rosa; a daughter, Katherine Crabtree of Medford, Ore.; a son, Alexander Popov of Carbondale, Ill.; and six grandchildren.