{ "title": "Mooney–Rivlin block in uniaxial, equibiaxial and pure-shear tension", "kind": "theory", "source": "Treloar's homogeneous modes of rubber testing (L. R. G. Treloar, The Physics of Rubber Elasticity, 3rd ed., Oxford 1975, ch. 10) for the decoupled compressible energy W = C₁₀ (Ī₁ − 3) + C₀₁ (Ī₂ − 3) + κ/2 (J − 1)²: principal Cauchy stresses σᵢ = (λᵢ/J) ∂W/∂λᵢ with the free stretch found so the free faces carry no stress (bisection; E = 3, ν = 0.49, C₀₁ = 0.2, C₁₀ = μ/2 − C₀₁)", "quantities": [ { "id": "uniaxial", "quantity": "axial Cauchy stress, uniaxial stretch λ = 2", "measure": { "command": "solve.probe", "params": { "step": "Uniaxial", "at": [ [ 1, 1, 1 ] ] }, "pointer": "/nodes/0/stress/0" }, "value": 2.736633402084229, "tolerance": { "relative": 1e-06 }, "reason": "a homogeneous deformation the hybrid hex20 represents exactly: the tolerance admits the Newton tolerance and rounding" }, { "id": "uniaxial_lateral", "quantity": "lateral displacement at (1, 1, 1), uniaxial: l − 1", "measure": { "command": "solve.probe", "params": { "step": "Uniaxial", "at": [ [ 1, 1, 1 ] ] }, "pointer": "/nodes/0/displacement/1" }, "value": -0.28647206688129256, "tolerance": { "relative": 1e-06 }, "reason": "a homogeneous deformation the hybrid hex20 represents exactly: the tolerance admits the Newton tolerance and rounding" }, { "id": "equibiaxial", "quantity": "in-plane Cauchy stress, equibiaxial stretch λ = 1.5", "measure": { "command": "solve.probe", "params": { "step": "Equibiaxial", "at": [ [ 1, 1, 1 ] ] }, "pointer": "/nodes/0/stress/0" }, "value": 2.842734818108988, "tolerance": { "relative": 1e-06 }, "reason": "a homogeneous deformation the hybrid hex20 represents exactly: the tolerance admits the Newton tolerance and rounding" }, { "id": "shear_xx", "quantity": "Cauchy stress along the stretch, pure shear λ = 2", "measure": { "command": "solve.probe", "params": { "step": "Shear", "at": [ [ 1, 1, 1 ] ] }, "pointer": "/nodes/0/stress/0" }, "value": 3.526124960232999, "tolerance": { "relative": 1e-06 }, "reason": "a homogeneous deformation the hybrid hex20 represents exactly: the tolerance admits the Newton tolerance and rounding" }, { "id": "shear_yy", "quantity": "Cauchy stress across, in the held direction, pure shear λ = 2", "measure": { "command": "solve.probe", "params": { "step": "Shear", "at": [ [ 1, 1, 1 ] ] }, "pointer": "/nodes/0/stress/1" }, "value": 1.506681177907714, "tolerance": { "relative": 1e-06 }, "reason": "a homogeneous deformation the hybrid hex20 represents exactly: the tolerance admits the Newton tolerance and rounding" } ] }