问题三:三角平台受谐波载荷作用,求结构响应
谐波载荷为作用在平台上面一点的集中力,幅值为10n,频率范围5hz~70hz
基本过程:
1、建模 2. 求模态解
3、用模态叠加法作谐分析
4. 观察结果
prep7 !建模
et,1,beam189
et,2,shell93
r,1,0.01
mp,ex,1,210e9
mp,prxy,1,0.3
mp,dens,1,7850
sectype, 1, beam, rect, seca, 0
secoffset, cent
secdata,0.005,0.008,0,0,0,0,0,0,0,0
k, ,0.5,k, ,0.5,,,
k, ,1,
k, ,1,1,
k, ,0.5,1,,
k, ,0.5,1,k, ,0.5,
a,4,5,6
lstr, 1, 5
lstr, 3, 4
lstr, 2, 6
lsel,s,line,,4,6
latt,1,1,1, ,7, ,1
lsel, ,all
lesize,all, ,10, ,1
lmesh,4,6
type, 2
mshape,0,2d
mshkey,1
amesh,1
finish
sol !为了使用模态叠加法谐分析
antype,2
modopt,lanb,20 !先取结构前20阶模态。
mxpand,20, ,0
modopt,lanb,20,0,0, ,off
ksel,s,kp,,1,3
dk,all, ,0,all
solve
finish
/post1 !最好事先看一下模态结果
set,list !以了解模态频率范围
finish
sol !模态叠加法谐响应分析
antype,3
hropt,msup
hrout,on
hropt,msup,20, ,
hrout,on,off,0
f,177,fy,-10, !施加10n的力在节点177的负y方向
harfrq,5,70, !载荷的强制频率范围
nsubst,200,kbc,1
alphad,5,
solve
finish
post26 !察看位移响应
file,,rfrq
numvar,20
nsol,2,139,u,y,plvar,2
finish
问题四:三角平台受一**谱激励,求应力分布和支反力
基本过程:
1、建模 2、求模态解
3、求谱解
4、扩展模态
5、模态合并
6、观察结果
prep7 !建模
et,1,beam189
et,2,shell93
r,1,0.01
mp,ex,1,210e9
mp,prxy,1,0.3
mp,dens,1,7850
sectype, 1, beam, rect, seca, 0
secoffset, cent
secdata,0.005,0.008,0,0,0,0,0,0,0,0
k, ,0.5,k, ,0.5,,,
k, ,1,
k, ,1,1,
k, ,0.5,1,,
k, ,0.5,1,k, ,0.5,
a,4,5,6
lstr, 1, 5
lstr, 3, 4
lstr, 2, 6
lsel,s,line,,4,6
latt,1,1,1, ,7, ,1
lsel, ,all
lesize,all, ,10, ,1
lmesh,4,6
type, 2
mshape,0,2d
mshkey,1
amesh,1
finish
sol !取前十阶模态
antype,2
modopt,lanb,10
ksel,s,kp,,1,3
dk,all, ,0,all
solve
finish
sol !谱分析
antype,8
spopt,sprs,10,1
svtyp,3
sed,0,1,0, !给出激励方向
freq,0.25,1.34,6.73,14.6,28.9,0,0,0,0 !激励谱
sv,0,0.00073,0.00016,0.00034,0.00034,0.00052,
solve
finish
sol !扩展模态
antype,2
expass,1
mxpand,10,0,0,1,0.001,
solve
finish
sol !模态合并
antype,8
srss,0.001,disp
solve
post1 !观察结果
set,list
input,,mcom
prrsol,f
finish
问题五:三角平台受时程载荷作用,求应力分布和变形过程。
基本过程:
1、建模 2. 施加随时间变化载荷,定义载荷步
3、求解 4. 在post1和post26中观察结果
prep7建模
et,1,beam189
et,2,shell93
r,1,0.01
mp,ex,1,210e9
mp,prxy,1,0.3
mp,dens,1,7850
sectype, 1, beam, rect, seca, 0
secoffset, cent
secdata,0.005,0.008,0,0,0,0,0,0,0,0
k, ,0.5,k, ,0.5,,,
k, ,1,
k, ,1,1,
k, ,0.5,1,,
k, ,0.5,1,k, ,0.5,
a,4,5,6
lstr, 1, 5
lstr, 3, 4
lstr, 2, 6
lsel,s,line,,4,6
latt,1,1,1, ,7, ,1
lsel, ,all
lesize,all, ,10, ,1
lmesh,4,6
type, 2
mshape,0,2d
mshkey,1
amesh,1
finish
sol antype,4
trnopt,full !完全法瞬态分析
ksel,s,kp,,1,3
dk,all, ,0,all
outres,all,1
alphad,5阻尼
time,2 !定义载荷曲线
autots,1
nsubst,50, ,1
kbc,0
sfa,all,1,pres,500
lswrite,1,
time,3
lswrite,2,
time,4
sfa,all,1,pres,150
kbc,1
lswrite,3,
time,5
sfa,all,1,pres,
lswrite,4,
lssolve,1,4,1, !求解
finish
post26观察变形随时间的变化
nsol,2,177,u,y,uyy
plvar,2
finish
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