non linear restraint

Dear all,

I am a new Caesar user.
i have a simple model which using resting support +Y on it. when i change the support to Y, it has a different result in restraint summary.
During static analysis, which one is more valid, using support type Y or +Y ?
How about the using of Gap for stopper or guide ?
is there any theory regarding this matter ?
your help will be highly appreciated.
thank you.

The fact that you got different results between the system with the "+Y" versus the "Y" is not surprising. A "+Y" is a nonlinear support, it has no stiffness in the "up" direction, while it is rigid in the "down" direction. A "Y" on the other hand is rigid in both the "up" and "down" directions. As soon as you have non-linear supports in your system, the software must iterate for a solution. This does not occur if you system consists of only linear supports.

Neither, they both have their applications. You should use which ever one is or will be actually in the real system in the field.

Again, these have their applications. You should use what actually reflects the real system.

Only experience and company procedures / policies.