单自由度弹簧质量系统振动

wrj001

*PARAMETER
B=10
NE=20
NEE=10
NL=NE+1
NE2=NE+2
NE3=NE+3
NA=(NE+1)*(NEE+1)
NW=NA-NE
NP1=NA+1
NP2=NA+2
NS1=NE*NEE+1
NS2=NE*NEE+2
*NODE,NSET=SH
1,0,0,0.0   
<NL>,10,0, 0.0
<NW>,0 ,5, 0.0   
<NA>,10,5,0.0
*NODE,NSET=SP
<NP1>,0,-5,0
<NP2>,10,-5,0
*NGEN,NSET=SOUTH
1, <NL>,1
*NGEN,NSET=NORTH
<NW>,<NA>, 1
*NFILL, NSET=PLATE
SOUTH, NORTH, <NEE>, <NL>
*ELEMENT, TYPE=S4
1,1,2,<NE3>,<NE2>
*ELGEN, ELSET=SHELL
1,<NE>,1,1,<NEE>,<NL>,<NE>
*Shell Section, elset=SHELL, MATERIAL=STEEL
<B>
*Material, name=STEEL
*Elastic
21000.,0.3
*density
1.85e-9
*SPRING, ELSET=SPG

1E-10
*ELEMENT,TYPE=SPRINGA,ELSET=SPG
<NS1>,1,<NP1>
<NS2>,<NL>,<NP2>
*Boundary
SH,1,1
SP,1,2
*STEP
*FREQUENCY, eigensolver=lanczos
20
*End Step