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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<strong>The</strong> Beam <strong>Element</strong> in Large Displacements<br />
We need to express <strong>the</strong> components V k<br />
ti , ZV k<br />
si <strong>of</strong> <strong>the</strong> vectors Vk t , V k s in<br />
terms <strong>of</strong> <strong>the</strong> nodal rotational degrees <strong>of</strong> freedom per node k:<br />
θ T k = [ θ k x θ k y θ k z<br />
This in linear analysis would be written as:<br />
V k t = θ k × t V k t<br />
V k s = θ k × t V k s<br />
but in <strong>the</strong> case <strong>of</strong> large displacements a second order Taylor approximation<br />
needs to be used:<br />
V k t = θ k × t V k t + 1 2 θ k × (θ k × t V k t )<br />
V k s = θ k × t V k s + 1 2 θ k × (θ k × t V k s)<br />
]<br />
Institute <strong>of</strong> Structural Engineering <strong>Method</strong> <strong>of</strong> <strong>Finite</strong> <strong>Element</strong>s II 40