Stephen P. Timoshenko

Although a world-renowned authority on theoretical and applied mechanics by the time he immigrated to America in 1922, Stephen P. Timoshenko (Stepan Prokofyevich Timofeyevich) solidified his mark on the profession while employed in the United States. Because of his unprecedented work while at Westinghouse Laboratories in Pittsburgh and the universities of Michigan and Stanford, he has been immortalized as “America’s Father of Engineering Mechanics.”

His accomplishments as a teacher, writer, engineer, and intellectual greatly impacted engineering education in the United States and beyond for all time. His many seminal books and papers on the mechanics of materials, statics and dynamics, vibrations, structural theory, stability, elasticity, torsion and buckling, and plates and shells remain in wide use today. His range of engineering and scientific contacts around the world was awesome, and his widespread international influence during his active years in both the United States and Russia are known in the profession as “The Timoshenko Era.”

While a distinguished professor and scholar at both Michigan and Stanford, he assembled internationally respected faculties that served as magnets for engineering scholars from all over the world. The list of his former pupils and colleagues make up a “Who’s Who” in engineering mechanics. Students and peers invoked (and continue to invoke) his name with awe, and being in his presence was like being among a deity.

During his time at Stanford, James Gere (a Timoshenko protégé, colleague, and co-author of the widely-used Mechanics of Materials) said, “Timoshenko always admonished his Ph.D. students not to make their doctoral dissertations their last scientific effort but to be constantly alert to new developments.”

According to Gere: “Timoshenko’s personal contributions to mechanics include the development of the energy method for dealing with problems in structural stability, the theory of lateral vibrations of beams (also known as the Timoshenko-beam theory), the concept of the shear center of beams, the theory of warping and torsion of structural members, and many other topics from elasticity theory. Much of the work he pioneered is now classical subject matter that is taught as standard topics in engineering courses.”

Timoshenko was the author of thirteen “gold-standard” textbooks and many papers on engineering mechanics. His works ranged from writings for undergraduate courses to those for advanced graduate students and research workers. Used by hundreds of thousands of engineering students and engineers throughout the world, his books and papers are available in numerous languages. His textbooks alone have been published in as many as five editions and translated into as many as thirty-five languages.

His best-known textbook Strength of Materials was published in Russia in 1911 and translated into English in 1930, whereupon it achieved tremendous success in the English-speaking countries. His textbooks are:

In addition to these seminal publications, Timoshenko also wrote two other books, Engineering Education in Russia and As I Remember, an autobiography, first published in Russian in 1963 then translated into English in 1968. All his books were frequently reprinted and often times updated with his former students as co-authors.

Stephen Timoshenko was born on December 23, 1878, in the village of Shpotovka (near Kiev) on the steppes of Ukraine, which was part of Russia at the time. He came from a long line of Ukrainians. His ambitious father Prokop Timofeyevich (Timoshenko), who was thirty-one years old when Stephen arrived, was born in a small cottage owned by Stepan Kandyba, a well-to-do Ukrainian landowner. Kandyba was married to Prokop’s older sister and young Prokop was brought up as a Kandyba family member with all the privileges.

Prokop studied land surveying and eventually became a successful professional surveyor. Later, he also became a landowner of some means, so his sons—Stephen and his two younger brothers Serhij and Vladimir—grew up in upper-middle-class comfort. Although his father was a good provider, Stephen related that his father was “a fanatic for work.” Most of Stephen’s upbringing was left in the hands of his mother, who was of Polish descent (her maiden name was Saranavskaja and her father a military man). She encouraged her children to take full advantage of all of their educational opportunities, and to constantly strive for success.

In the concluding decade of the nineteenth century, Russia was relatively stable and everyday life in the Timoshenko family’s pleasant rural surroundings was more or less tranquil. The youthful days of Stephen and his brothers were happy and carefree with plenty of open space and farmland to roam. In 1891, the grand Trans-Siberian Railroad project (1891–1916), between Moscow in the west and Vladivostok in the east, began making its way across the country. Many young Russians, including thirteen-year-old Stephen, dreamed of how exciting it would be to be a railroad engineer.

Timoshenko received his secondary schooling in the nearby town of Romny, from 1889 to 1896. His outstanding subject was mathematics, which fit into his early ambition to study civil-railroad engineering. His language studies were less successful and, even though his Russian had a strong Ukrainian accent (a characteristic that would remain with him his entire life), he was well read in the Russian classics. One of Stephen’s schoolmates and closest friends while in Romny was Abram Ioffe, who would one day be a famous physicist.

After earning a gold medal for superior scholarship at Romny and passing stringent college-entrance examinations, Timoshenko was accepted at the highly regarded Institute of Engineers of Ways of Communication (IEWC) at St. Petersburg. On his first trip to the coastal city in 1896, he was accompanied by his mother. His days and experiences in St. Petersburg began opening his eyes to the prospects of a world beyond his rural upbringing. While at IEWC, Stephen made a number of trips to western Europe, mostly during vacation periods, to observe activities and conditions there. These trips greatly stimulated his engineering mind and were the beginnings of the close associations he would forge with outstanding professionals in his field, particularly in Germany.

Timoshenko graduated from IEWC in 1901 and took a position there as a teacher. Simultaneously, he began serving his compulsory military service. Within a year, he was engaged in the institution’s mechanics laboratory, where his duties included assisting senior faculty members in their lectures on mathematics.

In 1902, following completion of his military service, twenty-four-year-old Timoshenko married Alexandra Archangelskaya, a medical school student. They would have three children—Gregory, Marina, and Anna. Gregory would become an electrical engineer (for years an imminent professor of electrical engineering at the University of Connecticut). Marina would marry a prominent Stanford Professor James Goodier (who was the co-author with Timoshenko of the textbook Theory of Elasticity). Anna would move to Germany and would provide a retreat there for her father in his twilight years.

In 1903, Timoshenko took a position as an instructor at the newly organized Polytechnic Institute of St. Petersburg (PISP). He worked under Viktor Kirpichyov, who introduced him to Lord Rayleigh’s Theory of Sound, the Castigliano Theorem and Rayleigh-Ritz Method. This exposure to creative scientific work was catalytic in inducing Timoshenko to become a teacher rather than a practicing engineer.

By 1904, thirty-six-year-old Nicholas II (1868-1918), who had become Tsar of Russia at age twenty-six when his father died unexpectedly at age forty-nine, had begun to exhibit a serious weakness for high-level governance and it was causing considerable unrest throughout the country. Because of this political turmoil and turbulence nationally, the 1904-1905 school year at PISP was quite unstable. The disastrous Russo-Japanese War (1904-1905), which saw the Tsar’s Army humiliated by the Japanese, increased student demonstrations and general unrest even further. At the end of the school term in 1905, the institute at St. Petersburg was abruptly closed and Timoshenko left unemployed.

He had been spending his summers in Europe, mostly in Germany, where he was becoming well acquainted with famous engineering scholars like August Foppl in Munich and Ludwig Prandtl (1875-1953) and Felis Klein at Gottingen. So when PISP shut down, Timoshenko temporarily moved to Germany to do advanced studies at the Munich Polytechnic Institute and the University of Gottingen (School of Philosophy), from which he graduated in 1905. Under the great Prandtl, who was head of applied mathematics at Gottingen and involved in epoch-making work on boundary layers in fluid flow and aerodynamics, Timoshenko developed a strong interest in resolving the analysis of buckling and torsion in structures. At the same time, he continued his work on elastic stability, also studying applied sciences, potential theory, and thermodynamics.

In the fall of 1906, Timoshenko became a professor at the Polytechnic Institute in Kiev (PIK) while working on his Ph.D., which he received in 1907. He was placed in charge of PIK’s strength of materials division. This return to his native Ukraine holding such a high position was a personal triumph for him, one that played an important part in his career and influenced his future personal life. In 1909, he was elected dean of the structural engineering department. During his time at PIK, he continued his pioneering scientific work on structural buckling and elastic stability, and published the first variant of his famous strength of materials textbook.

In 1911, the nationwide political turmoil in Russia was reaching the breaking point and student dissention on most campuses was festering out of control. Timoshenko was not unaffected. He and two other professors signed a protest against the minister of education. They were summarily fired from PIK and Timoshenko was once again without a job and steady income.

Ironically, he was awarded the 1911 Zhukovsky Prize from the Russian Academy of Science shortly after. With the prize came a medal, plaque, certificates, and a generous monetary award of 2,500 gold rubles. He and his wife used some of the money to take a vacation, which included an extended trip to England where he attended a mathematical congress at Cambridge. There, he met for the first time such leaders in his profession as Lord Rayleigh, August Love, Horace Lamb, and Levi Civita.

Timoshenko was greatly impressed with them and their work, and inspired by an impressive lecture given by a young intellectual from Gottingen, Theodore von Karman (1881-1963). They struck up a lifelong relationship. Throughout the proceedings, Timoshenko found himself hampered by his lack of fluency in English. He vowed to remedy the situation as soon as possible.

Returning to Russia in the fall of 1912, Timoshenko resumed part-time teaching assignments at several schools in St. Petersburg, including being a guest lecturer at his alma mater IEWC. Additionally, he did consulting work on the elastic stability of ship bulkheads for the Naval Ministry of St. Petersburg. During this time, he also continued to refine his theories on the buckling of structures, elasticity and beam deflections, and the analysis of structures on elastic foundations.

Timoshenko’s period of disgrace with the authorities officially ended in 1913 and he was made a professor at IEWC. Later, his assignment was extended to include teaching at the Electrical Engineering Institute of the Polytechnic Institute.

In the summer of 1914, after reorganizing the strength of materials department at IEWC, Timoshenko took his family on an extended vacation to Khapsalw on the Baltic. There he completed the proofreading of his first edition of Theory of Elasticity and refined his techniques for the analysis of the elastic stability of ship structures. During his vacation, World War I (1914-1918) began and, with it, the beginning of the end of the old world order as known by Timoshenko and other educated Russians of means.

Timoshenko returned to university life in St. Petersburg amid very unsettling times. His country did not fare well in the war, and the tsar became increasingly unpopular. Much of Nicholas’s unpopularity was due to the hypnotic fascination his wife Alexandra had for Grigori Rasputin (1871-1916), a self-proclaimed monk, holy man, and healer who had the tsarina convinced he and only he could cure her son Alexei who suffered from hemophilia, a hereditary disease from her side of the family that prevented blood from clotting properly. Hated by the nobility for his debauchery and abuse of power, and the influence he had on the policies of Nicholas, Rasputin was assassinated in 1916. By then he had considerably damaged the royal family’s reputation with the Russian people.

As Russia’s battle losses mounted during the early days of World War I and living conditions deteriorated, Nicholas abdicated his throne, ending his reign on March 15, 1917. Revolution and civil war then reached a fever pitch. The provisional government, formed after the tsar’s departure, was toppled by the Bolsheviks led by Lenin and Trotsky. Nicholas and Alexandra and their children were taken prisoners, and the final collapse of Russia’s ages-old political and social structure careened into its final days of disintegration.

These unsettling political, military, and societal events and times resulted in considerable difficulty for Timoshenko and his family and other anti-Bolsheviks. The worsening living conditions in Russia at the time were well portrayed in the movie Doctor Zhivago, based on the novel by Boris Pasternak.

In 1918, Timoshenko left St. Petersburg and returned to Kiev where he assisted Vladimir Vernadsky in establishing the Ukrainian Academy of Sciences—the oldest academy among the Soviet republics other than Russia. On July 16, the exiled tsar and his family were murdered by the Communists, under orders from Lenin.

During this time Timoshenko was in frequent contact with many of his former students and colleagues beyond Russia. All of them, despairing about the impossibility of order returning to Russia, urged him to flee the country. They told him of opportunities for an important professorship position in Yugoslavia. But he resisted leaving his country.

While he was serving with the Russian White Army in Kiev, the Red Army (the Bolsheviks) took over the city, soundly defeating the White Army. Timoshenko now had no choice—he had to leave, posthaste. Leaving all their possessions, he and his family took flight on the last refugee freight train out of Kiev. In their exodus, which was fraught with danger, they managed to stay just one step ahead of the Bolshevik cavalry, which was in hot pursuit. During these adventures, the Timoshenkos were helped on several occasions by former pupils and once were provided much-needed safe lodging by an admirer who had read one of his books. Years later, Timoshenko would tell his students at Stanford, “That was the most practical and useful result of all of my writings!”

The Timoshenkos eventually reached safety, winding through Warsaw, Poland, and Vienna, Austria, to get to Yugoslavia, which they reached on March 15, 1920. Once there, Timoshenko took a position as a professor at the newly established Zagreb Polytechnic Institute.

While at Zagreb, he delivered his lectures in Russian while using as many words in Croatian as he could. The students, though, were able to understand him well enough. With breaks in his teaching, he took brief trips to Western Europe and England, where he kept up his acquaintance with Love and met with other imminent scholars in his field, including R. V. Southwell and G. I. Taylor. He also continued his quest to improve his English. He and his English tutor translated some of his papers into English, sending them to Love, who had them published in England. Through this process the name of Timoshenko began to be known to English-speaking scholars of applied mechanics.

His career at Zagreb came to an end in 1922, when he received a “letter from America from a pupil of mine at the Petersburg Polytechnic, Viktor Zelow,” who was then working for the Vibration Specialty Company (VSC) in Philadelphia, Pennsylvania. VSC’s president (a Mr. Akimoff) was familiar with and highly impressed by Timoshenko’s work and quickly offered him a position with this company, which he took. The forty-three-year-old Timoshenko arrived in Philadelphia alone in June 22, 1922.

His first impression of America was not favorable; however, its opportunities were of interest to him. He sent for his wife and his youngest child, leaving the other two children in Germany. He wanted them to get a good education and he wasn’t impressed with American schools.

After a year with the VSC, Timoshenko joined the Research Laboratories of the Westinghouse Electric Corporation (WEC) in Pittsburgh. The intellectual atmosphere in East Pittsburgh during these years was strongly influenced by the breakthroughs in modern physics and the natural sciences. Many physicists and international figures in science came to lecture in Pittsburgh, which stimulated an interest in these matters. On his arrival at Pittsburgh, Timoshenko thus entered an intellectual environment that seems to have been made expressly for him and to which he made great contributions.

Richard Soderberg, a young emerging leader at WEC at the time, recalled, “He [Timoshenko] was in his forties, had a striking appearance, wore a beard and, to younger members of our group who came under his influence, he was a wise old man with a keen sense of humor.” When Soderberg and others at WEC had the opportunity to accompany Timoshenko to international conferences such as the Congress of Applied Mechanics in Zurich in 1926, Soderberg recalled, “We were privileged to sense the enormous range of his acquaintances in the scientific world, acquired from his years of travel and the wide distribution of his writings and theories.”

By 1927, Timoshenko had become well known in the United States and his widening influence in applied mechanics was being felt at all of the nation’s leading engineering colleges. He was invited to join the faculty as a professor of graduate mechanics at the University of Michigan. He accepted. Once there, he created the first bachelor’s and doctoral programs in engineering mechanics.

While at Michigan, Timoshenko realized his dream of joining applied and abstract sciences. One of his undertakings was a weekly seminar in which he brought together representatives from both camps. This led to a special Summer School of Applied Mechanics sponsored by the university. Distinguished teachers from universities in the United States and abroad attended, as did representatives from industry. Through these seminars pioneering leaders like Prandtl, von Karman, Southwell, Taylor, and H. M. Westergaard were brought together at Michigan.

It was during this period that he published some of his most famous textbooks and inaugurated a new era in applied mechanics in this country. He also continued to serve as a consultant for Westinghouse, staying friends with his contacts there. Even though travel during the Great Depression, which began with the U.S. stock market crash in 1929, was restricted, Timoshenko found ways to keep up his contacts both in his new country and across the Atlantic.

In the final years of the U.S. depression, Timoshenko took a professorship at Stanford University in 1936, a position he would hold until his “retirement” in 1944. Even though he was “retired,” he continued teaching and writing at Stanford for another decade or so.

Shortly after Timoshenko moved to California, Hitler invaded Poland and war in Europe was underway. Staying in contact with his brothers in Russia and all his European colleagues became difficult but not impossible. Once the United States became involved in World War II in 1941, however, government restrictions made travel much more complicated.

At Stanford, Timoshenko always showed up for class on the dot, no matter what. Gere recalled an incident where Timoshenko had been overseas and hadn’t been seen on campus for days, and on the day of class walked into the lecture hall just as the bell rang. He had arrived by taxi after riding nonstop on a train taken from where his ocean liner docked. He nonchalantly took off his coat and his fedora cap, which he always wore, and began lecturing to the amazement of everyone.

Said Gere, “His students were always fascinated by his classroom lectures, which were inspiring and long remembered. Because of his intimate knowledge of the history of mechanics and its past masters, he taught the classical subjects through the medium of their creators, thus bringing a human dimension to a topic that in lesser hands might have proved dull.”

Timoshenko often spent his non-wartime summers in Europe, where his favorite vacation spots were Switzerland, Germany, or England. On these sojourns he always met with colleagues at various universities. Whenever he took trips across the Atlantic he went by ship. He didn’t like airplanes, didn’t know how to drive, and didn’t like to use the telephone. With his aristocratic bearing and full head of silver-gray hair, the tall Timoshenko was an imposing figure on campus.

Gere, who affectionately called him Timi, said that when he knew Timoshenko: “He was always pleasant, and he always looked old. And while he was well known in professional circles all over the world, the number of people admitted to his innermost sphere of affection was not large. His former students had a special position; so did a small group of his early acquaintances in the United States. But one had the impression that real intimacy was reserved for his own family.”

By the end of World War II, Timoshenko’s two younger brothers had moved to and were employed in prominent positions in the United States, and the three brothers and their families, long separated, were able to more easily gather for family functions. Their relocation to America and nearness was especially treasured by the aging Timoshenko once his devoted wife passed away.

In 1945, shortly after World War II, Timoshenko was driven by military personnel all over West Germany, where he examined what was left of German industries and research laboratories, reporting his findings to Washington.

In 1958, he returned to Russia and Ukraine, his first visit to his homeland since his exodus in the 1920s. He was royally received—in stark contrast to earlier years when he vainly tried to get in touch with his aged father before he passed away but was refused access by the Communists.

In 1964, the eighty-six-year-old Timoshenko moved to Wuppertal, Western Germany, where his daughter Anna Hetzelt and her family resided.

During his professional career, Timoshenko received many honors and awards. Included among them was Stanford naming a wing of one of its main buildings the Timoshenko Laboratory for Engineering Mechanics, in 1951. In 1957, the American Society of Mechanical Engineers (ASME) established the Stephen Timoshenko Medal, commemorating Timoshenko’s contributions to the field of mechanical engineering as a world-renowned author and educator. As the first recipient of the medal, he was cited “for his invaluable contributions, personal example and guidance in bringing about a new era in applied mechanics.”

Among the other medals he received were the 1963 James Ewing (Institution of Civil Engineers of Great Britain), 1958 Cresson and 1944 Levy (Franklin Institute), 1948 Trasenster (Association des Ingenieurs Sortis de l’Ecole de Liege), 1947 James Watts International (Institute of Mechanical Engineers of Great Britain), 1947 Grande Medaille (Association des Ingenieurs—Docteurs de France), 1939 Lamme (American Society for Engineering Education, ASEE), 1935 Worcester Reed Warner (ASME), and 1911 Jourawski (IEWC).

Timoshenko was the recipient of honorary doctorate degrees from the University of Michigan, Lehigh University, University of Turin, Zagreb University, University of Bologna, University of Glasgow, Munchen Technische Hochschule, and Zurich Technical Institute.

Academies and societies he was elected to included Academia Nazionale dei Lincei, Rome (1948); Royal Society, London (1944); U.S. National Academy of Science (1941); French Academy of Science (1939); American Philosophical Society (1939); Polish Academy of Technical Sciences (1935); Russian Academy of Science (1928); and the Ukrainian Academy of Science (1918).

Other professional organizations he was active in were ASME, ASEE, American Institute of Aeronautics and Astronautics, American Geophysical Union, American Association for the Advancement of Science, Society for Experimental Stress Analysis, Society of Automotive Engineers, Gesellschaft fur Angewandte Mathematik und Mechanik, Verein Deutscher Ingenieure, and Association des Ingenieurs-Docteurs de France. He was the founder of the Applied Mechanics Division of ASME and was influential in starting the group’s Journal of Applied Mechanics, one of the world’s leading mechanics journals.

On his sixtieth birthday, Timoshenko was honored with a special book—“Stephen Timoshenko: Sixtieth Anniversary Volume”—which contained twenty-eight of his most distinguished papers in applied mechanics. In 1953, most of his research papers, many of them rare, were reprinted in “The Collected Papers of Stephen P. Timoshenko,” a 642-page volume.

In his later years, Timoshenko donated all medals, awards, and certificates along with his personal library, which contained countless rare and historic books and papers, to Stanford. A special “Timoshenko Room,” located in the school’s engineering library, was created to house his collection. He assigned the royalties from all his textbooks to the university. The rest of his modest assets he willed to his three children.

Timoshenko died on May 29, 1972, at the age of ninety-three, in Germany, at the home of his daughter Anna. His ashes were interred at Palo Alto Mesa Cemetery, Palo Alto, California, next to the grave of his wife.

Gere said, “His end came somewhat suddenly, after a short illness from a kidney ailment. For most of his life, Timi enjoyed excellent health and seemed always to be in high spirits—and his refreshing interest in life continued unabated into his last days.”

With the great man’s passing, a historic era ended. His legacy is that many were and will continue to be influenced by his extensive teachings and writings.