Hardy Cross

Educator, analyst, engineer, philosopher

By Professor Emeritus William J. Hall

Hardy CrossHardy Cross was Professor of Structural Engineering in the Department of Civil Engineering at the University of Illinois from 1921 to 1937. During that period, his technical achievements significantly changed the field of structural analysis and the understanding of structural behavior.

Cross was born February 10, 1885, on the family plantation in Nansemond County, near the Great Dismal Swamp, Virginia. He attended Hampden-Sydney College where he received B.A. and B.S. degrees in 1902 and 1903 respectively, at age 17 and 18. After teaching for a while at the Norfolk Academy, he entered Massachusetts Institute of Technology and received a B.S. degree in Civil Engineering in two years. Following a short period of additional teaching at the Norfolk Academy and work with the Missouri and Pacific rail roads, Cross earned an M.S. degree at Harvard University in 1911. Next was a seven-year stint at Brown University, followed by some professional posts in New York and Boston. In 1921 Cross joined the faculty at the University of Illinois at Urbana-Champaign (UIUC). He left in 1937 to head up the Department of Civil Engineering at Yale University until his retirement in 1953, when he moved to Virginia Beach, Virginia.

Most of Cross' technical achievements occurred during his time at UIUC. Many of his efforts were directed toward the development of techniques for refining and simplifying the monumental mathematical work required at that time to analyze elements of statically indeterminate buildings and bridges. Examples include his paper on Column Analogy in 1930, which led to a useful structural analysis tool. Although an earlier version was published in ACI in 1929, his more refined 1932 paper in the Transactions of the American Society of Civil Engineering (ASCE), "Analysis of Continuous Frames by Distributing Fixed-End Moments," served to reshape formal structural analysis for the next 30 years until computers started to enter the scene; his paper of eight pages on moment distribution led to 144 pages of discussion (nearly a record). His 1936 paper titled "The Relation of Analysis to Structural Design" continues even today, some 70 years later, to set a standard of practice that has not been superseded in the interim. This paper also focused on the importance of understanding structural behavior as part of analysis and design, and continues to be referenced often. His other 1936 publication (UIUC Engineering College Experiment Station Bulletin No. 286) was titled "Analysis of Flow in Networks of Conduits or Conductors" and serves to illustrate his insight into the importance of network theory; its immediate application was in the hydraulics field. During his 16 years at the University of Illinois, Cross authored 43 journal articles and Engineering Experiment Station Bulletins, all of great significance to the civil engineering profession. Many led to major changes in professional practice analysis procedures almost immediately, a feat that occurs rarely.

Cross was a consultant on many large engineering projects, and of particular note he was a member of the committee of engineers that prepared the report on the failure of the Tacoma Narrows Bridge. He served on many technical committees of ASCE, the American Concrete Institute and the American Railway Engineering Association.

He received numerous awards, including an Honorary Master of Arts from Yale University, Honorary Doctorate in Engineering from Lehigh University, an Honorary Doctor of Science from Hampden-Sydney, the Norman Medal and Honorary Membership in ASCE, the Wason Medal and Honorary Membership (posthumously) from the American Concrete Institute, the Lamme Medal from the Society for the Promotion of Engineering Education (now ASEE), and the Gold Medal of the Benjamin Franklin Institute of Philadelphia. He was elected a national honor member of Chi Epsilon. Just before his death he received the Gold Medal of the Institution of Structural Engineers of Great Britain. At that time, only a total of five Gold Medals had been granted in the first 50 years of the Institute, and Cross was the first American to be so honored.

Cross was a great teacher whose courses attracted the most brilliant students, many of whom chose teaching careers largely because of his example and inspiration. He was exacting in his requirements and would not tolerate loose and unclear thinking. His concern about matters of education led him to publish several papers in this field, one titled "Educational Inflation" was presented at MIT in 1937, and dealt primarily with the civil engineering curriculum.

Cross married Edith Hopwood Fenner in 1921; she passed away in 1956. Hardy Cross died in 1959, and both he and Edith are buried in the Wright Family Plot in Ivy Hill Cemetery, Smithfield, Virginia.