Hardy Cross (born in Nansemond County (Virginia), 1885-1959), was an American structural engineer and the creator of the structural calculation method known as Cross's method or moment distribution method, designed for the calculation of large reinforced concrete structures. This method was used frequently between 1935 and 1960, when it was replaced by other methods. Cross's method made possible the efficient and safe design of a large number of reinforced concrete buildings for an entire generation.

In addition, he is also the author of the Hardy Cross method for modeling complex water supply networks. Until recent decades, it was the most common method to solve a large number of problems.[1]​.

NOTE: the following text has been translated from the English article.

He earned a Bachelor of Science degree in civil engineering from the Massachusetts Institute of Technology in 1908, and then entered the bridge department of the Missouri Pacific Railroad in St. Louis, where he remained for a year. He then returned to Norfolk Academy in 1909. A year after graduation he studied at Harvard where he obtained the MCE degree in 1911. Hardy Cross developed the method of moment distribution while working at Harvard University. He then worked as an assistant professor of civil engineering at Brown University, where he taught for 7 years. After a brief return to general engineering practice, he accepted a position as professor of structural engineering at the University of Illinois at Urbana-Champaing in 1921. At the University of Illinois Hardy Cross developed his method of moment distribution and influenced many young civil engineers. His students in Illinois had a hard time arguing with him because he was difficult to listen to.

The structural analysis required for large constructions of reinforced concrete structures in 1950 was a formidable task. This is an attribute of the engineering profession, and for Hardy Cross, that there are so few faults here. When engineers have to calculate stresses and deflections in a statically indeterminate frame, they inevitably revert to what was known as the "Moment Distribution" or "Hardy Cross Method." In the moment distribution method, the moments at the fixed ends of the frames are gradually distributed to the adjacent members in a number of steps such that the system eventually reaches its natural equilibrium configuration. However, the method was still an approximation but could be solved to be very close to the real solution.