STRUCTURE magazine•March 2005 40 great achievementsSTRUCTURE Hardy Cross By Richard G. Weingardt A ManAheadofHisTime most significant ofthesemethods,the for continuous beamsandframes. The the waystresses couldbecalculated coming intovogue–that greatly simplified structures using reinforced-concrete were complicated andhighlyindeterminate analysis–atatimewhen of structural andpracticalmethods They containednew books andpaperswere widelytranslated. theoretician.structural His engineering for hisinnovations asaneducatorand half ofthe20thcentury, worldrenowned engineeringinthemid-to-later- structural figuresthe mostimportant inAmerican they wantedhisfullattention. learned whichwashisbestsidewhen students–and hiscolleagues–quickly Because hewasdeafinoneear, eager dig untiltheproblem isclearlydefined.” constantly ask,“Why, why, why, and Hardy alwayschallengedhispupilsto developed a“great love forengineering.” the engineeringgiantCH2M-Hill, likes ofHolly Cornell,co-founderof and hisactions. greatness by Cross’s high-spiritedwords budding engineerswere inspired to from theBible andtheclassics.Many often sprinklinginhislectures quotes and engineeringideasinhisteachings, an engineer, whomeshedhumanities one ofakind–aphilosopheraswell as fitting thatmoldoranyother. He was educated Cross, however, wasfar from full ofcalculations.” The classically protector inhisfront pocketandasatchel stumbling across campuswithapen- by definitionatechnocrat,somebody take forgrantedthatanengineeris Hardy oftenstated,“People [mistakenly] societal progress. merits ofengineeringinforwarding a stirringkeynoteaddress exaltingthe in Manchester, England, Cross delivered ceremonies, atthegroup’s convention in 1958.During theGold Medal Institute’s celebrations 50thanniversary when was73years old,duringthe He received thecelebratedBritish award who alwaysthoughtoutsidethebox. engineeringsuperstar and structural Engineers, wasafar-seeinginnovator of theBritish Institution ofStructural awarded thehighlycoveted Gold Medal Cross waswithoutquestiononeof It wasunderhistutelagethatthe During thelatterhalfofhiscareer, Professor Cross, thefirstAmerican magazine

Copyright is illustratedin and simpleexampleoftheMethod bute fixed-end moments.(Abasic approximations torapidlydistri- in 1930,madeuseofconverging Cross Method–first introduced Moment-Distribution orHardy very short time,you couldactuallyanalyze short very He developed aprocedure by which, ina no computersofthekindwe have today. mathematical equations.Andthere were up withseveral thousandsimultaneous high-rise building,you wouldend to designahighwaybridgeor “In Hardy Cross’s day, ifyou wanted University Professor Zia Razzaq, with awe. Hardy Cross wasalwaysinvoked difficult structures, thenameof about methodsfordesigning talked ofthe20thcentury part whenever engineers inthelatter addressed complicatedproblems; revolutionized how theprofession long before thecomputerage.It andcivilengineering, structural complex problems inthefieldsof innumerable equationstosolve mathematical taskofcalculating did wassimplifythemonumental Figure 1–Abasicapplicationofthe “Hardy Cross Moment-Distribution” Method. According toOld Dominion Essentially, whatCross’s methods Figure 1 .) of theCross materialsattheUniversity ofIllinois.) Hardy Cross (William J.Hall istheowner and“keeper” have becomereality whentheydid. would have remained dreams andnot methods, manyengineeringprojects all thestresses init.” Without Cross’s complexstructure andcalculate a very

© Born on February 10, 1885 in Nanse- projects on the east coast and served as engineering/construction failures, includ- great achievements mond County, Virginia, Hardy was assistant engineer to the well-established ing the Tacoma Narrows Bridge and the younger of two sons of Thomas H. Charles T. Main. Charity Hospital in New Orleans. In his Cross and Eleanor Wright, both from On September 5, 1921, 36-year-old later years, Professor Cross was a much prominent southern families. His father Hardy married Edythe Hopwood Fenner in demand speaker as well as engineering Thomas H., a student at the University from Providence, Rhode Island. They consultant. of Virginia when the Civil War broke would have no children, and she would Cross was the recipient of honorary out, dropped out of college and joined precede him in death by three years. degrees from Yale (1937), Lehigh (1937) the Confederate Army. He served in it for The year 1921 also marked Cross’s return and Hampden-Sydney (1934), and nu- its entirety, even though he was wounded to fulltime teaching when he took a posi- merous prestigious engineering honors during several bloody battles. tion as professor of including ASCE’s Norman Medal (1933) A dozen-and-a-half years after the at the University of Illinois. By then, he and the ACI’s Wason Medal (1936). war was over (and shortly before Hardy’s was well known for his insightful writings, As the first award-winner of the Am- older brother Thomas Peete was born including a voluminous report “River Flow erican Society of Engineering Education’s in 1879), Thomas H. was elected to Phenomena and Hydrology of the Yellow Lamme Medal in 1944, Hardy was cited the Virginia House of Delegates. He River, China” and a popular monograph for “his insistence on the great respon- and Eleanor then permanently re- sibilities of the individual teacher located to Norfolk, Virginia, to raise and for his scorn of the superficial their family, which would include in education–and for his pre- only two boys. eminence in building men who © Both of their sons–Thomas and Copyright are carrying forward his own high Hardy–were excellent students. standard for straight, hard thinking Hardy followed in his older in the teaching and practice of brother’s footsteps, graduating from engineering.” Norfolk Academy and then attending In his book Engineers and Ivory Hampden-Sydney College to become Towers, a collection of his talks, Cross a schoolteacher. He was just 17 when stated that what man wants and what he graduated as valedictorian from he needs are not always identical. Hampden-Sydney with a bachelor’s “Engineering does not tell men of arts degree in 1902. One year what they should want or why they later, he received a bachelor’s of want it. Rather it recognizes a need science degree. That same year, his and tries to meet it.” His advice to 62-year-old father, who had recently would-be professors was, “One who been appointed the local postmaster is to become a teacher of engineering after serving as a Deputy U.S. should be trained primarily to be an Marshall, died. engineer, and association with the Young Cross immediately took a profession outside the ivory towers of position with his local alma mater, learning is absolutely essential.” Norfolk Academy, teaching English Tattered dust cover of one of Cross’s well-read books attests Less than a year after his triumph and mathematicsSTRUCTURE so he could be near to his longtime popularity as an author. in England in 1958, Professor Cross his newly widowed mother to comfort received the Benjamin Franklin her – and help her run a boarding house. on the graphic analysis of arch structures, (scientific) Institute of Philadelphia’s cel- Three years later, Hardy magazinewas found at which was being used as a text at Harvard’s ebrated Gold Medal. It would prove to Massachusetts Institute of Technology graduate school of engineering. be a final tribute to a great career and a (MIT) studying . Within In 1937, Cross left the mid-west and great engineer, for soon after, on February two years, in 1908, he had earned an returned to the east coast, accepting his 12, 1959, the 74-year-old engineering MIT bachelor’s of science degree. final academic position as Chair of the educator extraordinaire quietly passed After working briefly as a bridge Department of Civil Engineering at Yale, away in Virginia Beach, Virginia. engineer for the Missouri-Pacific Railway a position he held until his retirement in As a lasting tribute to the American from1908 until 1909, Hardy migrated the early 1950s. icon–and in recognition of his wide- back to Norfolk to teach for one more Over his career, Cross was especially reaching influence–an in-depth “Hardy year. He returned to Boston and, in 1911, active in several professional groups: the Cross: Illustrious Citizen” exhibit was received a master’s of science degree in civil American Society of Civil Engineers established in 1997, at the Isle of Wright engineering from . (ASCE), American Concrete Institute County Museum in Virginia.▪ Taking an assistant professor’s position (ACI), American Academy of Arts and at shortly after, he Sciences, American Institute of Consult- Richard G. Weingardt, PE, CEO taught civil engineering at Brown for ing Engineers, American Railroad En- of Richard Weingardt Consultants, Inc., seven years. In 1918, he left the Un- gineering Association, Connecticut Society Denver, CO, is the author of eight books. iversity to get involved in the practice of of Civil Engineers, Royal Society of Arts His latest Engineering Legends, being structural and hydraulic engineering in and Western Society of Engineers. published by ASCE Press, is due out the Boston and New York areas. During He was also prominently involved in early 2005. Many of the book’s this period, he worked on a number of in the investigation of several historic featured engineering greats are U.S. structural engineers.

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