Approach for Overcoming Numerical Inaccuracy Caused by Load Discontinuity
Publication: Journal of Engineering Mechanics
Volume 133, Issue 5
Abstract
It was found that the discontinuity at the end of an impulse will lead to numerical inaccuracy as this discontinuity will result in an extra impulse and thus an extra displacement in the time history analysis. In addition, this extra impulse is proportional to the discontinuity value at the end of the impulse and the size of integration time step. To overcome this difficulty, an effective approach is proposed to reduce the extra impulse and hence the extra displacement. In fact, the novel approach proposed in this paper is to perform a single small time step immediately upon the termination of applied impulse, whereas other time steps can be conducted by using the step size determined from accuracy consideration in period. The feasibility of this approach is analytically explored. Further, analytical results are confirmed by numerical examples. Numerical studies also show that this approach can be applied to other step-by-step integration methods. It seems that to slightly complicate the programming of dynamic analysis codes is the only disadvantage of this approach.
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Acknowledgments
The writer gratefully acknowledges the financial support for this study provided by the National Science Council, Taiwan, R.O.C., under Grant No. UNSPECIFIEDNSC-93-2211-E-027-012.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 133 • Issue 5 • May 2007
Pages: 555 - 565
Copyright
© 2007 ASCE.
History
Received: Sep 20, 2005
Accepted: Oct 3, 2006
Published online: May 1, 2007
Published in print: May 2007
Notes
Note. Associate Editor: Arif Masud
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