The Finite Element Method for the Analysis of Non-Linear and ...
The Finite Element Method for the Analysis of Non-Linear and ...
The Finite Element Method for the Analysis of Non-Linear and ...
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Viscoplasticity<br />
<strong>The</strong> elastic response <strong>of</strong> viscoplastic materials can be represented in one-dimension<br />
by Hookean spring elements. Rate-dependence can be represented by nonlinear<br />
dashpot elements.<br />
Plasticity can be accounted <strong>for</strong> by<br />
adding sliding frictional elements. In <strong>the</strong><br />
figure E is <strong>the</strong> modulus <strong>of</strong> elasticity, λ is<br />
<strong>the</strong> viscosity parameter <strong>and</strong> N is a<br />
power-law type parameter that<br />
represents non-linear dashpot<br />
σ = λ dɛ 1/N<br />
. <strong>The</strong> sliding element can<br />
dt<br />
have a yield stress (σy) that is strain<br />
rate dependent, or even constant, as<br />
shown in Figure (c).<br />
Institute <strong>of</strong> Structural Engineering <strong>Method</strong> <strong>of</strong> <strong>Finite</strong> <strong>Element</strong>s II 31