Can you help me?

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cyz1654
Posts: 29
Joined: Sun May 11, 2008 3:16 am
Location: Zhejiang

Can you help me?

Post by cyz1654 »

I use PressureDependMultiYield material and quad-up element ,and I want to know whether the soil liquefys or not .The equation is Pore pressure ratio = excess pore pressure /initial effective vertical stress.My problem is about the initial effective vertical stress.What I use is :
recorder Element –ele $eleNum -file $fName -dT $deltaT material $GaussNum backbone $p1 <$p2 …>
But when the $GaussNum is 1 2 3 4,the output are the same,why?

Please help me
avytin
Posts: 75
Joined: Fri Dec 08, 2006 5:41 pm
Location: MiT

Post by avytin »

Try this command to get results:
e.g.(gauss point 1, is you want output for elems 1-100)

recorder Element -file stress_1.txt -time -eleRange 1 100 material 1 stress
cyz1654
Posts: 29
Joined: Sun May 11, 2008 3:16 am
Location: Zhejiang

Post by cyz1654 »

[quote="avytin"]Try this command to get results:
e.g.(gauss point 1, is you want output for elems 1-100)

recorder Element -file stress_1.txt -time -eleRange 1 100 material 1 stress[/quote]


Thank you!But my question is when I use:
recorder Element -file stress_1 -time -ele 1 material 1 stress
recorder Element -file stress_2 -time -ele 1 material 2 stress
recorder Element -file stress_3 -time -ele 1 material 3 stress
recorder Element -file stress_4 -time -ele 1 material 4 stress

data in stress_1,stress_2,stress_3,stress_4 are the same,it is right?
avytin
Posts: 75
Joined: Fri Dec 08, 2006 5:41 pm
Location: MiT

Post by avytin »

I am using pressuredependmultiyield02 model and the results are different. I've worked with opensees 1.74, 1.75, 2.0.

Did you consider using psmy02 model? I think it takes a little bit better the stress level dependency of dilatancy.
cyz1654
Posts: 29
Joined: Sun May 11, 2008 3:16 am
Location: Zhejiang

Post by cyz1654 »

in the command manual,FourNodeQuadUP Element,the is a note:

The valid queries to a quadUP element when creating an ElementRecorder are 'force', 'stiffness', or 'material matNum matArg1 matArg2 ...', where matNum represents the material object at the corresponding integration point.

I try the command :recorder Element -file stress -ele 1 -time force

the data is :
5000 22.239 44.951 0.0002325 -35.973 57.9983 0.0002675 -22.9257 -35.141 -0.0002325 35.2863 -48.1883 -0.0002675

the first 5000 is time,could you konw what does the other data mean?
hsafti
Posts: 68
Joined: Thu Apr 22, 2010 5:38 am
Location: Braunschweig

Re: Can you help me?

Post by hsafti »

Dear cyz1654,

I wonder if you had luck with your questions. I wish to know what are the positions of Gauss points in a QuadUP element and if they coincide with the nodes how are the nodes ordered GP 1,2,3 and 4?

Thanks
Hisham ElSafti
Hisham El Safti
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