FEM

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FEM
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FEM
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Fig. 2.1 Model of the analysis.
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0
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V?j1,fa????????????????????
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Newton-Raphson?
NLFEM
( fj1 )
Newton-Raphson?
Modal FEM0
( fj1fa )
Newton-Raphson?
Modal FEMa
??NLFEM???Modal FEMa
Modal FEMb
fj1fb
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?????(??????, fj1 )
?????(??????, fj1jj )
?????(??????, f yij1 )
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?????????(ex.??????????????)
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Table 2.1 Specification of the beam.
Table 2.2 Specification of the external force.
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fajj (j2,3,,8)FRFs , displacements and
strains
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Fig. 2.1
FRFs obtained by FEM, single-mode(fj1,
j0) and two-mode(fj1jjj2,3,,8)
analyses.
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Fig. 2.2
Displacements and normal strains obtained by FEM,
single-mode(fj1, j0) and
two-mode(fj1jjj2,3,,8) analyses at
75Hz.
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fayi (i1,2,,8) FRFs , displacements and
strains
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Fig. 2.3
FRFs obtained by FEM, single-mode(fj1,
i0) and two-mode(fyij1i1,2,,8)
analyses.
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Fig. 2.4
Displacements and normal strains obtained by FEM,
single-mode(fj1, i0) and
two-mode(fyij1i1,2,,8) analyses at
75Hz.
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but
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Fig. 3.1
Modes and normal strains obtained by FEM at 45 ,
55 , 65 , 75 Hz.
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Vq qHz????NLFEM???
y q??????????
j q ??????????
f yqjq and yqj1
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f yqjq and yqj1difference of
FRF , sqrt(k/m)
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Fig. 3.2
Differences between NLFEM and Modal FEM, and
sqrt(k/m) / w1 by using fyqjq and
yqj1 (q45,46,,70) .
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Fig. 3.3
FRFs obtained by FEM, single-mode(fj1) and
two-mode(fy5j1 and yw1/2pj1 )
analyses.
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1??????
Normal Mode????
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Fig. 4.1
Comparison between the backbone curve obtained by
the present method and that by Yamaki and Mori.
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Fig. 4.2
Comparison between the normal mode and the time
history obtained by the numerical integration.
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Table 4.1 Specifications of the plates.
Table 4.2 Specifications of the external forces.
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Fig. 4.3 Finite element model of a rectangular
plate.
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Fig. 4.4
Comparison between the backbone curve obtained by
the present method and the frequency ratios in
other papers.
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FEM???
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