{"id":8712,"date":"2018-05-26T01:02:51","date_gmt":"2018-05-25T17:02:51","guid":{"rendered":"http:\/\/www.jdcui.com\/?p=8712"},"modified":"2026-02-16T22:43:39","modified_gmt":"2026-02-16T14:43:39","slug":"midas-genabaqusmidas2abaqus-midas-gen-verification-example-eigen-9-eigenvalue-and-static-analysis-of-a-5-level-pyramid-building-under-lateral-loads-midas-gen-%e9%aa%8c%e8%af%81%e5%ae%9e","status":"publish","type":"post","link":"http:\/\/www.jdcui.com\/?p=8712","title":{"rendered":"[Midas2Abaqus] Midas Gen Verification Example Eigen-9: Eigenvalue and static analysis of a 5- level pyramid building under lateral loads [ Midas Gen \u9a8c\u8bc1\u5b9e\u4f8b Eigen-9: 5\u5c42\u91d1\u5b57\u5854\u7ed3\u6784\u7684\u7279\u5f81\u503c\u5206\u6790\u53ca\u4fa7\u5411\u6c34\u5e73\u529b\u9759\u529b\u5206\u6790]"},"content":{"rendered":"

\u30101\u3011Problem Description ( Midas Gen Verification Example Eigen-9: Eigenvalue and static analysis of a 5- level pyramid building under lateral loads)<\/strong><\/p>\n

Perform the eigenvalue analysis of a pyramid building. Calculate the natural frequencies
\nand the displacements of each floor due to static lateral loads.<\/p>\n

\"\"<\/p>\n

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\u30102\u3011MODEL Properties<\/strong><\/p>\n

Dimension <\/strong><\/em><\/p>\n

Length 70 \u00d7 12 in Width 70 \u00d7 12 in Height 5 \u00d7 12.125 \u00d7 12 in
\nFloor mass M = 100 psf = 1.7972 \u00d7 10 -6 kips \u2219 sec 2 \/in
\nNodes 42 ~ 45 are the master nodes for the 4 th ~ 1 st levels in a decending order
\nrespectively.
\nGravitational acceleration g = 386.4 in\/ sec 2
\nMass and rotational mass moment of inertia at each floor.<\/p>\n

Floor Master node Mass, M X =M Y Rotational mass moment of inertia, I m
\n4 42 0.0507246 238.6087
\n3 43 0.2028986 3817.7391
\n2 44 0.4565217 19327.3044
\n1 45 0.8115942 61083.8261<\/p>\n

Element<\/strong> <\/em>
\nBeam element<\/p>\n

Material<\/strong> <\/em>
\nModulus of elasticity E = 29500 ksi
\nPoisson\u2019s ratio
\n\u03bd = 0.3<\/p>\n

Section Property <\/strong><\/em><\/p>\n

Horizontal beams Area A = 13.5 in 2
\nEffective Shear Area A sy = 6.5016 in 2
\nA sz = 6.1105 in 2
\nTorsional stiffness I xx = 1.22 in 4<\/p>\n

Moment of inertia I yy = 712.0 in 4 (Strong axis)
\nI zz = 22.5 in 4 (Weak axis)
\nDiagonals Area A = 11.7 in 2
\nEffective Shear Area A sy = 2.97 in 2
\nA sz = 7.532 in 2
\nTorsional stiffness I xx = 1.12 in 4
\nMoment of inertia I yy = 146.0 in 4 (Strong axis)
\nI zz = 49.1 in 4 (Weak axis)<\/p>\n

Boundary Condition<\/strong> <\/em><\/p>\n

Nodes 6 ~ 41 (at an increment of 5 ) ; Constrain all DOFs.
\nNodes 42 ~ 45 ; Constrain Dx, Dy and Rz of all nodes at each
\nlevel to these nodes. (Master nodes)<\/p>\n

\u30103\u3011Midas Gen Model<\/strong><\/p>\n

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\u30104\u3011Midas 2 Abaqus Model<\/strong><\/p>\n

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\u30105\u3011Abaqus Model<\/strong><\/p>\n

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\u30106\u3011Results<\/strong><\/p>\n

Static\u00a0 Load Case<\/strong><\/em><\/p>\n

\"\"<\/p>\n

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Eigen Analysis Load Case<\/strong><\/em><\/p>\n

\"\"<\/p>\n

mode 1<\/strong><\/p>\n

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mode 2<\/strong><\/p>\n

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mode 3<\/strong><\/p>\n

\"\"<\/p>\n

mode 5<\/strong><\/p>\n

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mode 6<\/strong><\/p>\n

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mode 8<\/strong><\/p>\n

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mode 9<\/strong><\/p>\n

\u30107\u3011Comparison of Results<\/strong><\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n
\u3000<\/strong><\/td>\nFEQUENCY(CYCLES\/TIME)<\/strong><\/td>\n\u3000<\/strong><\/td>\n<\/tr>\n
Node<\/strong><\/td>\nMidas GEN<\/strong><\/td>\nABAQUS<\/strong><\/td>\n<\/tr>\n
1<\/strong><\/td>\n8.27E+00<\/strong><\/td>\n8.3266<\/strong><\/td>\n<\/tr>\n
2<\/strong><\/td>\n8.27E+00<\/strong><\/td>\n8.3266<\/strong><\/td>\n<\/tr>\n
3<\/strong><\/td>\n1.59E+01<\/strong><\/td>\n16.078<\/strong><\/td>\n<\/tr>\n
4<\/strong><\/td>\n1.59E+01<\/strong><\/td>\n16.078<\/strong><\/td>\n<\/tr>\n
5<\/strong><\/td>\n1.64E+01<\/strong><\/td>\n16.39<\/strong><\/td>\n<\/tr>\n
6<\/strong><\/td>\n2.51E+01<\/strong><\/td>\n25.447<\/strong><\/td>\n<\/tr>\n
7<\/strong><\/td>\n2.51E+01<\/strong><\/td>\n25.447<\/strong><\/td>\n<\/tr>\n
8<\/strong><\/td>\n3.37E+01<\/strong><\/td>\n33.732<\/strong><\/td>\n<\/tr>\n
9<\/strong><\/td>\n4.19E+01<\/strong><\/td>\n42.509<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n\n\n\n\n\n\n\n\n\n
\u3000<\/strong><\/td>\nDisplacement X<\/strong><\/td>\n\u3000<\/strong><\/td>\n<\/tr>\n
Node<\/strong><\/td>\nMidas GEN<\/strong><\/td>\nABAQUS<\/strong><\/td>\n<\/tr>\n
1<\/strong><\/td>\n1.81E+00<\/strong><\/td>\n1.637<\/strong><\/td>\n<\/tr>\n
42<\/strong><\/td>\n1.39E+00<\/strong><\/td>\n1.30235<\/strong><\/td>\n<\/tr>\n
43<\/strong><\/td>\n1.03E+00<\/strong><\/td>\n0.998134<\/strong><\/td>\n<\/tr>\n
44<\/strong><\/td>\n7.10E-01<\/strong><\/td>\n0.697188<\/strong><\/td>\n<\/tr>\n
45<\/strong><\/td>\n3.82E-01<\/strong><\/td>\n0.374851<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n

PS. \u4e24\u8005\u6709\u5dee\u5f02\u7684\u5176\u4e2d\u4e00\u4e2a\u539f\u56e0\u662f\uff0cABAQUS\u7528\u7684\u662f\u6b27\u62c9\u4e24\u5355\u5143\uff0c\u6ca1\u6709\u8003\u8651\u526a\u5207\u6548\u5e94<\/span>\u3002<\/strong><\/em><\/p>\n

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