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Kinematic hardening

Problem description: Consider the rod shown subjected to cyclic loading. Compute elastic-plastic response using linear kinematic hardening. See also examples V.3, V.5 and V.6.

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Mesh: Use the following element types:
ITE=6--see appendix A.1, four quadrilaterals
ITE=56--see appendix B.1, four hexahedra.
Material properties: $E=2\times 10^5$ MPa, $\nu=0.3$.
Prandtl-Reuss-von Mises model with linear kinematic hardening.
$\epsilon_p$:    0.000 0.015 0.040  
$\sigma_Y$:    350 650 1150 [MPa]
QY:    0 300 800 [MPa]
Support: Clamped at x=0. Statically determinate.
Loading: $\sigma_{xx}=\pm 400$ MPa, 3 cycles.
Solution: For detailed explanation see section V.3. The plastic modulus Ep is computed as

\begin{displaymath}E_p=\frac{650-350}{0.015}=\frac{1150-350}{0.04}=2\times10^4\,\mbox{[MPa]}
\end{displaymath}


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Reloading the bar to 350 MPa the hysteresis loop closes and the cycle will stabilize.

Loading $\Delta\sigma$ $\epsilon_p$ H $\sigma_{Yc}$ $\sigma_{Yt}$
0 0 0 350 -350 350
+400 50 $2.5\times10^{-3}$ 350 -300 400
-400 100 $7.5\times10^{-3}$ 350 -400 300
+400 100 $12.5\times10^{-3}$ 350 -300 400
-400 100 $17.5\times10^{-3}$ 350 -400 300
+400 100 $22.5\times10^{-3}$ 350 -300 400
-400 100 $27.5\times10^{-3}$ 350 -400 300


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Next: BEAM6P4 Up: Plasticity Previous: OUTPUT