Genesis, Degeneracy and Progress of Clapeyron Theorem in Linear Elasticity

Document Type : Research Paper

Authors
1 Alma Mater and past professorship: University of Naples Federico II, Naples, Italy
2 Department of Structures for Engineering and Architecture, University of Naples Federico II, Via Claudio, 21 - 80125 Naples, Italy
Abstract
About two centuries have passed since Émile Clapeyron conceived a simple formula for expressing the energy stored in a linearly elastic structure which is standing during the dynamic process of loading from an initial to a final state of static equilibrium. Standing means displacement and deformation fields are small enough to allow for a geometric linearised theory to be applicable in structural formulations. Clapeyron’s theorem is often introduced in an over-restricted context. A formulation in which essential assumptions are explicitly stated and redundant elements are eliminated is the prerequisite for detecting range of validity and possible extensions. Physical evidence and notion of virtual work clarify the claim of thermodynamic paradox concerning a gap between mechanical work done by loading forces and storage of elastic energy in the structure. Beauty and power of Clapeyron’s theorem, as equality based on variational conditions of equilibrium and on linear elasticity, are thus recovered. The standard result is extended for application to structural models, including kinematic constraints, prestress, impressed distortion and is reshaped with a formulation of incremental elasticity based on the notion of elastic state and pertinent linearised approximation.
Keywords
Subjects

Publisher’s Note Shahid Chamran University of Ahvaz remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

[1] Lamé, G., Clapeyron, B., Mémoire sur l’équilibre intérieur des corps solides homogènes. (Suite). Journal für die reine und angewandte Mathematik, 7, 1831, 381–413. http://eudml.org/doc/146751.
[2] Lamé, G., Clapeyron, É., Mémoire sur l’équilibre intérieur des corps solides homogènes. Mém. Divers Savants, IV, 1833, 463–562.
[3] Lamé, G., Leçons sur la théorie mathématique de l’élasticité des corps solides. Bachelier, Paris, 1852.
[4] Clapeyron, É., Mémoire sur le travail des forces élastiques dans un corps solide élastique déformé par l’action de forces extérieures. Comptes Rendus Acad. Sci. Paris, XLVI, 1858, 208–212.
[5] Love, A.E.H., A Treatise on the Mathematical Theory of Elasticity. 4th ed., Cambridge University Press, 1927; Reprint, Dover Publications, New York, 1944.
[6] Sokolnikoff, I.S., Mathematical Theory of Elasticity. McGraw-Hill, New York, 1st ed. 1946, 2nd ed. 1956.
[7] Fosdick, R.L., Truskinowsky, L., About Clapeyron’s Theorem in Linear Elasticity. Journal of Elasticity, 72, 2003, 145–172.
[8] Man, C.-S., Fosdick, R.L. (eds.), The Rational Spirit in Modern Continuum Mechanics. Essays and Papers Dedicated to the Memory of Clifford Ambrose Truesdell III. Kluwer Academic Publishers, New York, 2005.
[9] Gurtin, M.E., Variational principles in the linear theory of viscoelasticity. Arch. Rat. Mech. Anal., 13, 1963, 179–191.
[10] Brun, L., Sur deux expressions, analogues à la formule de Clapeyron, donnant l’énergie libre et la puissance dissipée pour un corps viscoélastique. C.R. Acad. Sci. Paris, 261, 1965, 41–44.
[11] Mandel, J., Cours de Mécanique des milieux continus, t. II, Annexe XXI, Viscoélasticité, 799–802. Gauthier-Villars, Paris, 1966.
[12] Huet, C., Minimum theorems for viscoelasticity. Eur. J. Mech. A/Solids, 5(11), 1992, 653–684.
[13] Huet, C., Extended Clapeyron formulae for viscoelasticity problems in the time domain and application to the boundarycondition effect in random composite bodies. Int. J. Mech. Phys. Solids, 49, 2001, 675–706.
[14] Romano, G., Continuum Mechanics and Electrodynamics: Geometric Foundations. About 1800 pages (in completion), 2024, https://gioprof1941.web.app.
[15] Romano, G., Barretta, R., Diaco, M., The Geometry of Nonlinear Elasticity. Acta Mech., 225(11), 2014, 3199–3235.
[16] Euler, L., Institutiones calculi differentialis cum eius usu in analysi finitorum ac doctrina serierum, vol.1, ch.7, 1755. English transl.: Foundations of Differential Calculus. https://scholarlycommons.pacific.edu/euler-works/212.
[17] Romano, G., Barretta, R., Advancements in Continuum Mechanics and Electrodynamics by a spacetime geometric approach. Acta Mech., 235, 2024, 4357–4399.
[18] Romano, G., Barretta, R., Diaco, M., Genesis and Progress of Virtual Power Principle. Acta Mech., 233, 2022, 5431–5445.
[19] Romano, G., Barretta, R., Diaco, M., Spacetime evolutive equilibrium in Non-Linear Continuum Mechanics. Continuum Mech. Thermodyn., 30, 2023, 1859–1880.
[20] Kirchhoff, G.R., Über das Gleichgewicht und die Bewegung eines unendlich dünnen elastischen Stabes. J. reine angew. Math. (Crelle), 56, 1859, 285–313. De Gruyter-online, 2009, https://doi.org/10.1515/crll.1859.56.285.