قالب:Elastic moduli

صيغ التحويل
Homogeneous isotropic linear elastic materials have their elastic properties uniquely determined by any two moduli among these; thus, given any two, any other of the elastic moduli can be calculated according to these formulas.
K= E= λ= G= ν= M= Notes
(K,E) K E 3K(3KE)9KE 3KE9KE 3KE6K 3K(3K+E)9KE
(K,λ) K 9K(Kλ)3Kλ λ 3(Kλ)2 λ3Kλ 3K2λ
(K,G) K 9KG3K+G K2G3 G 3K2G2(3K+G) K+4G3
(K,ν) K 3K(12ν) 3Kν1+ν 3K(12ν)2(1+ν) ν 3K(1ν)1+ν
(K,M) K 9K(MK)3K+M 3KM2 3(MK)4 3KM3K+M M
(E,λ) E+3λ+R6 E λ E3λ+R4 2λE+λ+R Eλ+R2 R=E2+9λ2+2Eλ
(E,G) EG3(3GE) E G(E2G)3GE G E2G1 G(4GE)3GE
(E,ν) E3(12ν) E Eν(1+ν)(12ν) E2(1+ν) ν E(1ν)(1+ν)(12ν)
(E,M) 3ME+S6 E ME+S4 3M+ES8 EM+S4M M

S=±E2+9M210EM

There are two valid solutions.
The plus sign leads to ν0.
The minus sign leads to ν0.

(λ,G) λ+2G3 G(3λ+2G)λ+G λ G λ2(λ+G) λ+2G
(λ,ν) λ(1+ν)3ν λ(1+ν)(12ν)ν λ λ(12ν)2ν ν λ(1ν)ν Cannot be used when ν=0λ=0
(λ,M) M+2λ3 (Mλ)(M+2λ)M+λ λ Mλ2 λM+λ M
(G,ν) 2G(1+ν)3(12ν) 2G(1+ν) 2Gν12ν G ν 2G(1ν)12ν
(G,M) M4G3 G(3M4G)MG M2G G M2G2M2G M
(ν,M) M(1+ν)3(1ν) M(1+ν)(12ν)1ν Mν1ν M(12ν)2(1ν) ν M

The stiffness matrix (9 by 9, or 6 by 6 in Voigt notation) in Hooke's law (in 3D) can be parametrized by only two components for homogeneous and isotropic materials. One may choose whichever pair one prefers among the elastic moduli given below. Some of the possible conversions are listed in the table.

المصادر

  • G. Mavko, T. Mukerji, J. Dvorkin. The Rock Physics Handbook. Cambridge University Press 2003 (paperback). ISBN 0-521-54344-4