stodola vianello
DESCRIPTION
dTRANSCRIPT
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Datos:
g = 980 cm/seg2
Pesos
W1 = 135 ton
W2 = 131 ton
W3 = 127 ton
MASAS
m1 = 0.137755102 ton-seg2/cm
m2 = 0.133673469 ton-seg2/cm
m3 = 0.129591837 ton-seg2/cm
RIGIDEZ
k1 = 359 ton/cm
k2 = 296 ton/cm
k3 = 127 ton/cm
SOLUCIN
Se puede trabajar con los nmeros exactos o con proporciones
m1= 1.063 m2= 1.031 m3= 1
k1= 2.827 k2= 2.331 k3= 1
1ra ITERACION
{?} 1 2 3
{Fi} 1.063 2.062 3 m*1^2
{V} 6.125 5.062 3 m*1^2
{X} 2.167 2.172 3 m*1^2 /k
{X} 2.167 4.339 7.339 m*1^2 /k
2da ITERACION
{? cx} 1 2.002 3.387
{Fi} 1.063 2.064 3.387 m*1^2
{V} 6.514 5.451 3.387 m*1^2
{X} 2.304 2.338 3.387 m*1^2 /k
{X} 2.304 4.642 8.029 m*1^2 /k
3ra ITERACION
{? cx} 1 2.015 3.485
{Fi} 1.063 2.077 3.485 m*1^2
{V} 6.625 5.562 3.485 m*1^2
{X} 2.343 2.386 3.485 m*1^2 /k
{X} 2.343 4.729 8.214 m*1^2 /k
4ta ITERACION
{? cx} 1 2.018 3.506
{Fi} 1.063 2.081 3.506 m*1^2
{V} 6.65 5.587 3.506 m*1^2
{X} 2.352 2.397 3.506 m*1^2 /k
{X} 2.352 4.749 8.255 m*1^2 /k
{? cx} 1 2.019 3.51
1
1 = 2.019
3.51
(2.352+4.749+8.255) m*1^2/k = (1+2.019+3.51)
1 = 20.4126 rad/seg
Periodo Fundamental
T = 0.3078 seg
Determina la primera frecuencia, el periodo fundamental
y su modo de vibracin
MTODO ITERATIVO DE STODOLA VIANELLO
Ingresar peso o masa, no ambos
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Criterio para asumir frecuencias
1 = 2 = 3 = 4 =
1 3 5 7
Condicin del problema
2^2 = 5 2^2 = 2080 2 = 45.607017 rad/seg
1^2 T2 = 0.137767952 seg
3^2 = 15 3^2 = 6240 2 = 78.99367063
1^2
2do MODO DE VIBRACIN
[ X ] 1 1.243 -0.918
[ F1 ] 287.04 346.449 -248.227
[ V ] 359 71.96 -274.489
[ X ] 1 0.243 -2.161
26.262 ton = 0
1
2 = 1.243
-0.918
3er MODO DE VIBRACIN
[ X ] 1 -0.696 -0.067
[ F1 ] 861.12 -581.967 -54.35
[ V ] 359 -502.12 79.847
[ X ] 1 -1.696 0.629
-134.197 ton no es suficiente
Tanteando 2 = 6280
[ X ] 1 -0.715 0.026
[ F1 ] 866.64 -601.687 21.226
[ V ] 359 -507.64 94.047
[ X ] 1 -1.715 0.741
-72.821 ton = 0
3^2 = 6280 3 = 79.24645102 rad/seg
T3 = 0.079286646 seg
1
3 = -0.715
0.026
R = F3 - V3 =
R = F3 - V3 =
^2 =6240rad/seg
^2 =6280rad/seg
R = F3 - V3 =
MTODO ITERATIVO DE HOLTZER
Para calcular las dems frecuencias y modos de
vibracin
^2 =2080rad/seg