Pierre Couplet

Pierre Couplet was the son of Claude-Antoine Couplet (1642–1722), the treasurer of the Académie Royale des Sciences in Paris. The young Couplet entered the Académie in 1696 as a pupil of his father. Afterwards, Couplet went to Lisbon, where he learned Portuguese, and then signed on for a two-and-a-half-year astronomy research expedition to Brazil. In 1699 he became a member of the reformed Académie and in 1700 took part in the campaign to measure geographical longitude led by Cassini II. Later, Couplet was promoted to Professeur Royal de Mathématiques des Pages de la Grand Écurie and in 1717 to treasurer of the Académie – posts that his father had held previously. He presented several essays on astronomy, earth pressure theory, masonry arch theory, mansard roofs, pipe hydraulics and mechanics of carriages and sledges to the Académie; most significant among these was his second essay on masonry arch theory, which began the tradition of analysing the collapse mechanisms of arches. In Heyman's historical reconstruction of the history of masonry arch theories from the viewpoint of the ultimate load method, Couplet's theory therefore plays a very important role [Heyman, 1982]. After Couplet's death, the Académie refrained from the Éloge customary for its members. His work on masonry arch theory was therefore gradually forgotten: "It is only unfortunate that the work was slowly forgotten, so that fifty years later Coulomb, in seeming ignorance of Couplet's contribution, had to rediscover much of the theory” [Heyman, 1976, pp. 35–36].

Main contributions to structural analysis:

• De la poussée des voûtes [1729/1731];
• Seconde partie de l'éxamen de la poussée des voûtes [1730/1732]

Source: Kurrer, Karl-Eugen The History of the Theory of Structures, Wilhelm Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH, Berlin (Deutschland), ISBN 3-433-01838-3, 2008; p. 723-724