CFVR4602 - EAK 2000: Seismic Analysis (elastic spectrum) Y-axis
Seismic Analysis on a 1 DOF beam according to EAK 2000
This example compares spectrum accelerations given by CivilFEM to accelerations obtained when solving on a 1 DOF beam and to the correct EAK 2000 spectum accelerations.
The model is 1 element beam with only 1 DOF, which direction the CivilFEM spectrum is set (the rest of the DOF are constrained). A different mass is applied at the free end of the beam for the beam period to be equal to the 20 CivilFEM spectrum points. After solving, the mass acceleration is obtained and compared to the CivilFEM spectrum acceleration and to the correct value. Therefore, this example checks the following results:
- CivilFEM spectrum is defined correctly by comparing to the correct value
- CivilFEM spectrum is applied correctly and response acceleration is equal to spectrum acceleration
Element types used in the model: BEAM4, MASS21 Needed CivilFEM Modules: |
|
| Model Statistics | |
| Number of elements | 1 |
| Number of nodes | 2 |
| Number of civil materials | 1 |
| Number of cross sections | 1 |
| Number of shell vertices | 0 |
Log file: CFVR4602.DAT
FINISH ~CFCLEAR,,1 NomFile='CFVR4602' /TITLE, %NomFile%, EAK 2000: Seismic Analysis (elastic spectrum) Y-axis ! ---------------------------------------------------------------------- ! Model definition ! ---------------------------------------------------------------------- ! CivilFEM Setup: Code & Units ~UNITS,,LENG,CM ~UNITS,,TIME,S ~UNITS,,FORC,KP ~CODESEL,,,,,EAK2000 /PREP7 ! Preprocessor ! ---------------------------------------------------------------------- ! Materials: A-42 ~CFMP,1,LIB,STEEL,EA,A42 ! Modify density (Rho = 0) ~CFMP,1,USER ~CFMP,1,DatGen,RHO,,0 ! Element Types ET,1,BEAM4 ! Type 1: 3D Beam ET,2,MASS21 ! Type 2: Mass ! Sections ~SSECLIB,1,1,1,1 !IPE 80 ~BMSHPRO,1,BEAM,1,1,,,4,,0,, ! Nodes L = 10 ! L : Bar length N, 1 N,10,L ! Elements TYPE,1 MAT ,1 REAL,1 EN,1,1,10 EPLOT ! Parameters *GET,AR20,EX,1 ! Ex : Elastic Modulus ~CFGET,AR22,SECTION,1,MECHPROP,A,,2 ! Area : Bar area ~CFGET,AR23,SECTION,1,MECHPROP,IZZ,,2 ! Izz : Moment of inertia ~CFGET,AR24,SECTION,1,MECHPROP,IYY,,2 ! Iyy : Moment of inertia ! Seismic Spectrum ~DEFSPEC,ALL,I,A,ELASTIC,1,5,1.3,0.9 pi = 3.141592654 ! ---------------------------------------------------------------------- ! DATA CHECK ! ---------------------------------------------------------------------- ! Data comparision number NComp = 40 NComp_ch = 0 ! Marix dim. *DIM,LABEL,CHAR,Ncomp,1 *DIM,LABEL_CH,CHAR,Ncomp_ch,1 *DIM,VALUE,,Ncomp,3 *DIM,VALUE_CH,CHAR,Ncomp_ch,3 *DIM,TOLER,,Ncomp,2 *DO,ARG1,1,20 /PREP7 ~CFGET,AR26,SEISM,,SPEC,TH,,ARG1,1 ! Period ! Labels LABEL(ARG1,1) = 'Sa(%ARG1%)y' LABEL(20+ARG1,1) = 'Sa(%ARG1%)y' AR25=12*AR20*AR23/L**3 ! Bending rigidity around Z axis AR27=AR25*(AR26/(2*pi))**2 ! Mass applied at end R,2,0,AR27 TYPE,2 MAT, 1 REAL,2 EN,2,10 FINISH /SOLU ! Displacements D,1,,,,,,ALL D,10,,,,,UX, ,UZ,ROTX,ROTY,ROTZ ~MODLSOL,1 ~CMBMOD,NONE,HORIZONT,NONE,0,0.0001 ! Query results *GET,ARG5,NODE,10,U,Y ! Correct values VALUE(20-ARG1+1,1)=ARG5*AR25/AR27 ! Acceleration ! Obtained values ~CFGET,VALUE(20-ARG1+1,2),SEISM,,SPEC,SDH,,ARG1,1 ! Y components of elastic spectrum ~CFGET,VALUE(40-ARG1+1,2),SEISM,,SPEC,SDH,,ARG1,1 ! Y components of elastic spectrum ! CivilFEM gives the spectrum Normalized by gravity. ! To compare it must be changed to acceleration user units. VALUE(20-ARG1+1,2) = VALUE(20-ARG1+1,2)*981 VALUE(40-ARG1+1,2) = VALUE(40-ARG1+1,2)*981 /PREP7 EDELE,2 *ENDDO ! Correct values ! ---------------------------------------------------------------------- VALUE(40,1) = 38.2590 VALUE(39,1) = 76.5180 VALUE(38,1) = 114.7770 VALUE(37,1) = 153.0360 VALUE(36,1) = 191.2950 VALUE(35,1) = 229.5540 VALUE(34,1) = 267.8130 VALUE(33,1) = 306.0720 VALUE(32,1) = 344.3310 VALUE(31,1) = 382.5900 VALUE(30,1) = 382.5900 VALUE(29,1) = 359.6553 VALUE(28,1) = 336.6792 VALUE(27,1) = 313.6756 VALUE(26,1) = 290.7409 VALUE(25,1) = 267.8130 VALUE(24,1) = 244.8576 VALUE(23,1) = 221.9091 VALUE(22,1) = 198.9468 VALUE(21,1) = 175.9914 ! Warning and error tolerances ! ---------------------------------------------------------------------- *DO,II,1,NComp TOLER(II, 1)= 0.1 $ TOLER(II, 2)= 0.1 *ENDDO ! ---------------------------------------------------------------------- ! Results Comparison ! ---------------------------------------------------------------------- COMPARA.MAC |
Results
| Label | Target | CivilFEM | Ratio | Tolerance |
| Sa(1)y | 175.99 | 175.99 | 1.000 | 0.1 |
| Sa(2)y | 198.95 | 198.95 | 1.000 | 0.1 |
| Sa(3)y | 221.9 | 221.9 | 1.000 | 0.1 |
| Sa(4)y | 244.86 | 244.86 | 1.000 | 0.1 |
| Sa(5)y | 267.81 | 267.81 | 1.000 | 0.1 |
| Sa(6)y | 290.77 | 290.77 | 1.000 | 0.1 |
| Sa(7)y | 313.72 | 313.72 | 1.000 | 0.1 |
| Sa(8)y | 336.68 | 336.68 | 1.000 | 0.1 |
| Sa(9)y | 359.63 | 359.63 | 1.000 | 0.1 |
| Sa(10)y | 382.59 | 382.59 | 1.000 | 0.1 |
| Sa(11)y | 382.59 | 382.59 | 1.000 | 0.1 |
| Sa(12)y | 344.33 | 344.33 | 1.000 | 0.1 |
| Sa(13)y | 306.07 | 306.07 | 1.000 | 0.1 |
| Sa(14)y | 267.81 | 267.81 | 1.000 | 0.1 |
| Sa(15)y | 229.55 | 229.55 | 1.000 | 0.1 |
| Sa(16)y | 191.3 | 191.29 | 1.000 | 0.1 |
| Sa(17)y | 153.04 | 153.04 | 1.000 | 0.1 |
| Sa(18)y | 114.78 | 114.78 | 1.000 | 0.1 |
| Sa(19)y | 76.518 | 76.518 | 1.000 | 0.1 |
| Sa(20)y | 38.259 | 38.259 | 1.000 | 0.1 |
| Sa(1)y | 175.99 | 175.99 | 1.000 | 0.1 |
| Sa(2)y | 198.95 | 198.95 | 1.000 | 0.1 |
| Sa(3)y | 221.91 | 221.9 | 1.000 | 0.1 |
| Sa(4)y | 244.86 | 244.86 | 1.000 | 0.1 |
| Sa(5)y | 267.81 | 267.81 | 1.000 | 0.1 |
| Sa(6)y | 290.74 | 290.77 | 1.000 | 0.1 |
| Sa(7)y | 313.68 | 313.72 | 1.000 | 0.1 |
| Sa(8)y | 336.68 | 336.68 | 1.000 | 0.1 |
| Sa(9)y | 359.66 | 359.63 | 1.000 | 0.1 |
| Sa(10)y | 382.59 | 382.59 | 1.000 | 0.1 |
| Sa(11)y | 382.59 | 382.59 | 1.000 | 0.1 |
| Sa(12)y | 344.33 | 344.33 | 1.000 | 0.1 |
| Sa(13)y | 306.07 | 306.07 | 1.000 | 0.1 |
| Sa(14)y | 267.81 | 267.81 | 1.000 | 0.1 |
| Sa(15)y | 229.55 | 229.55 | 1.000 | 0.1 |
| Sa(16)y | 191.29 | 191.29 | 1.000 | 0.1 |
| Sa(17)y | 153.04 | 153.04 | 1.000 | 0.1 |
| Sa(18)y | 114.78 | 114.78 | 1.000 | 0.1 |
| Sa(19)y | 76.518 | 76.518 | 1.000 | 0.1 |
| Sa(20)y | 38.259 | 38.259 | 1.000 | 0.1 |
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