Hallo sir,

i m beginner in caesar II software, i would like to know the thumb rule used in caesar II software.
in general consideration people follow some factor of safety.
for displacement --> in Y direction it should around 3 mm, please correct me if i m wrong . is there any consideration for X and Z direction.
for sustain --> stress,code ratio should be around 70 to 75%
and in expansion case it should around 75 to 80%.
Is there any thumb rule for loading in sustain & OPE. condition.

thanks in advance.
regards.

Design Codes such as B31.3 already build in factors of safety, so why add more ? There are no 'rules of thumb' like this that I am aware of. In any case it's likely that only one or two locations in a pipe network will approach the allowable stress limit.

Certainly there is no such limit on 'Y' or vertical displacement. It's good to limit mid-spans to some small figure to avoid pooling, but more like 15mm (assuming the reference was indeed to mid-spans).

X and Z (horizontal) displacements are often limited by pipe support requirements such as shoe length, or rack spacing.