Dynamic Stiffness based Computation of Response for Framed Machine Foundations
IR@SERC: CSIR-Structural Engineering Research Centre, Chennai
View Archive Info| Field | Value | |
| Title |
Dynamic Stiffness based Computation of Response for Framed Machine Foundations
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| Creator |
Lakshmanan, N.
Gopalakrishnan, N. Rama Rao, G.V. Sathish Kumar, K. |
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| Subject |
Machine foundations
Dynamic stiffness method Spectral finite element Wittrick-william's algorithm Strum number Major's method Dynamic constriant problem |
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| Description |
The paper deals with the applications of spectral finite element method to the dynamic
analysis of framed foundations supporting high speed machines. Comparative performance of approximate
dynamic stiffness methods formulated using static stiffness and lumped or consistent or average mass
matrices with the exact spectral finite element for a three dimensional Euler-Bernoulli beam element is
presented. The convergence of response computed using mode superposition method with the appropriate
dynamic stiffness method as the number of modes increase is illustrated. Frequency proportional discreti-
sation level required for mode superposition and approximate dynamic stiffness methods is outlined. It is
reiterated that
the results of exact dynamic stiffness me
thod are invariant wi
th reference to the
discretisation level. The Eigen-frequencies of the system are evaluated using William-Wittrick algorithm
and Sturm number generation in the
LDL
T
decomposition of the real part of the dynamic stiffness matrix,
as they cannot be explicitly evaluated. Major’s method for dynamic analysis of machine supporting
structures is modified and the plane frames are replaced with springs of exact dynamic stiffness and
dynamically flexible longitudinal frames. Results of the analysis are compared with exact values. The
possible simplifications that could be introduced for a typical machine induced excitation on a framed
structure are illustrated and the developed program is modified to account for dynamic constraint
equations with a master slave degree of freedom (DOF) option.
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| Date |
2009
2009 2009 |
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| Type |
Article
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| Identifier |
Journal of Geomechanics and Engineering, Vol.1, No.2, 2009, pp.121-142
http://hdl.handle.net/123456789/453 |
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| Language |
en
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| Rights |
It is tried to respect the rights of the copyright holders to the best of the knowledge. If it is brought to our notice that the rights are violated then the item would be withdrawn.
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| Publisher |
Taylor & Francis
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