• 대한기계학회논문집A
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• 제20권12호
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• pp.3792-3803
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• 1996

Since the skew beam element has two curvatures which are a curvature and a torsion, spatial behavior of curved beam which cannot be included in one plane can be anlayzed by emploting the skew beam element. The $C^{0}$-continuous skew beam element shows the stiffness locking phenomenon when full integration is employed. The locking phenomenpn is characterized by two typical phenomena ; one is the much smaller displacement thant the exact one and theother is the undelation phenomenon is stress distribution. In this paper, we examine how unmatched coefficient in the constrained energy brings about the locking by Reduced Minimization theory. We perform the numerical ones. These comparisons show that uniformly full integration(UFI), which employs full integration for the constrained energy, entails the locking phenomenon. But the use of uniformly reduced integration(URI) of selectively reduced integration(SRI), which employs reduced integration for constrained energy, does not produce the significant errors of displacements of the undulation phenomenon in stress distribution since they do not entails the locking, Additionally, the error due to the approximated parameters for describing the geometry of skew beam is examined.d.

• 대한기계학회논문집
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• 제19권8호
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• pp.1799-1809
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• 1995

The applicability of the field-consistency paradigm, which was originally employed for analysis of locking due to constrained energy having the second power of a strain, is extended to the constrained energy having a quadratic form of strain. For the extension, nearly-incompressible plane strain problem is considered by introducing the concept of reduced minimization. The field-consistent analysis of the plane strain problem leads to a clear and systematic understanding on the relation amongst constraints imposed on element, spurious constraint -free optimal points, and integration order used.