{ "title": "A steel bar held at its ends and heated past yield (small strain)", "kind": "theory", "source": "Uniaxial J2 plasticity with linear hardening (Simo and Hughes, Computational Inelasticity, Springer 1998, §2.3) with the additive thermal strain: the bar's total axial strain is held at zero, so its mechanical strain is −α ΔT and σ = −(σ_y + E_t (α ΔT − σ_y/E)) once α ΔT exceeds σ_y/E", "quantities": [ { "id": "sigma", "quantity": "axial stress, ΔT = 300 (α ΔT = 3.6·10⁻³, 2.9 times the yield strain)", "measure": { "command": "solve.probe", "params": { "step": "Heat", "elements": [ 2 ] }, "pointer": "/elements/0/stress/0/0" }, "value": -254.65346534653466, "tolerance": { "relative": 1e-08 }, "reason": "a homogeneous uniaxial state the elements represent exactly" }, { "id": "plastic_strain", "quantity": "equivalent plastic strain", "measure": { "command": "solve.probe", "params": { "step": "Heat", "elements": [ 2 ] }, "pointer": "/elements/0/plastic_strain/0" }, "value": 0.0023267326732673297, "tolerance": { "relative": 1e-07 }, "reason": "(|σ| − σ_y)/H, as for the stress" } ] }