Component | Element type | Constitutive model | Constitutive model (MPa) | Shell thickness (mm) |
---|---|---|---|---|
Cortical bone | Triangular shell | Elastic–Plastic | \(E\)= 12,000 \(G\)= 1250 \(\sigma\) yield = 189.8 \(v\)= 0.3 | C1-C3 = 0.51 C4 = 0.55 C5 = 0.62 C6 = 0.66 C7 = 0.70 T1 = 0.30 |
Cancellous bone | Tetrahedral | Elastic–Plastic | \(E\)= 442 \(G\)= 51 \(v\)= 0.3 | N/A |
Bony endplate | Triangular shell | Elastic–Plastic | \(E\)= 5600 \(G\)= 300 \(\sigma\) yield = 36.7 \(v\) = 0.3 | 0.5 |
Nucleus pulpous | Hexahedral | Incompressible fluid | \(k\)= 1720 | N/A |
Annulus fibrosus matrix | Hexahedral | Mooney-Rivin | \(A\)= 0.18 (constants) \(B\) = 0.045 (constants) | N/A |
Annulus fibrosus fibers | Quadrilateral membrane | Orthotropic nonlinear elastic | \(E\) c = 0.01–7.1 \(v\) ab = 0.3 | 0.25 |
ligaments | Quadrilateral membrane | Orthotropic nonlinear elastic | \(E\) c = 0.4–23.3 \(v\) ab = 0.3 \(v\) ca = \(v\) cb = 0.49 | ALL = 1.5 PLL = 1.7 LF = 1.3 FCL = 1.1 ISL C2-C5 = 1.4 ISL C6-T1 = 1.0 |