Benoit Paul Emile Clapeyron
(1799-1864)

Benoit Paul Emile Clapeyron was a famous French structural engineer and bridge designer; he taught engineering at the École des Ponts et Chaussées in Paris. It appears that Clapeyron’s theorem, which states that the work of the external loads acting on a linearly elastic body is equal to the strain energy, was first published in 1833.

From Mechanics of Materials, 4th Ed., by J.M. Gere and S.P. Timoshenko, PWS Publishing, 1997, pp. 835-42.