Spring with different stiffness in compession and tension

I am working on Direct Transient response analysis.

I am modeling the shock isolator as a bush. But the problem is the stiffness value in one direction , compression stiffness and tension stiffness are not same.

Can any one help in modeling such a bush.

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Tommy_21858

For this you need an PBUSHT card with TABLED1 for your damper direction. In the table you can define the stiffness depending on the elongation.

mpvnaresh

Hi ..Thanks for response.

I have only two stiffness values (K compression, K tension) I have no deflection vs Stiffness data.

Is there any way i can do this.

Tommy_21858

You can also create a curve / table (force vs deflection) with two values. For example:

 TABLED1        5  LINEAR  LINEAR +           -1.0  -100.0    -0.1  -100.0     0.0     0.0     0.1    100. $--1---][--2---][--3---][--4---][--5---][--6---][--7---][--8---][--9---] +            1.0    100.    ENDT

mpvnaresh

Thank you

mpvnaresh

I am using PBUSHT in DTRAN solution . This is not working for me.

can any body help in this ( Is PBUSHT compatible with DTRAN ? )

The data i have is attached . Please help me in modelling the same.

<?xml version="1.0" encoding="UTF-8"?>

Tommy_21858

In my opinion pbusht in DTRAN should work. But I haven't use it together until now. Maybe you can add your table entries or model?

Best regards