Soil-Structure Interaction

[raffah]

Hello everyone,

I´m a fresh user of ansys, and im needing a little help modeling my problem.

I´m analyzing the arching effect that occurs in buried structures, namely, box culverts. This effect causes the load over the structure to be larger than the heigth of soil above her (for flexible structures).

In my model i simulate the backfill process using kill/alive elements command. The elements i'm using for diferent components are:

PLANE82 for soil, PLANE183 for concrete, CONTA172 and TARGE169 for soil-structure interaction (SSI).

Since the box culverts are the junction of two separated pieces, in the connection between them i'm also using CONTA172 and TARGE169 to simulate the connection, only with differents keyoptions and real constants.

Here i get the following error:
"real constant 1 has been referenced by at least elemens types 5 and 3, one of which is contact element type"

Don't know what i'm doing wrong. I join an attachment with part of the code i'm creating so somenone can help me.

Also, are the interface elements (INTER193 and INTER203) suitable for simulating SSI?

What would be the best key options to aply to CONTA172 for the SSI?

The PIPE elements i'm using are for plotting results only.


Thanks in advance,

Best regards,

raffah

http://files.engineering.com/getfil...&file=ATRAVESSAMENTO_INFERIOR_BOX_CULVERT.txt

 

[PriamEngineering]

Nice neat input deck!!!

Contacts and targets have to share the same real constants for each contact pair... yours are all different. Try issuing the Cncheck command to see where the problem lie.

your deck should look something like this....
asel,,,
nsla,s,1
esln
type,contact
real,1
esurf

asel,s,,,
nsla,s,1
esln
type,target
real,1
esurf

http://www.priamengineering.co.uk