my current calculation consists of a Tank which operates on +100C and -20C. it settles down by 150mm during operation. my load cases are as follows:

1- W+T1+P1
2- W+T2+P1
3- W+T1+D1+P1 (D1: settlement+tank bulge+radial expansion)
4- W+T2+D1+P1
5- W+P1 (sus)
6- L3-L5 (exp)
7- L4-L5 (exp)
8- L6+L7 (exp) (COMBINATION METHOD: abs)

if I add case 8, the displacement of the nozzle will be 300mm downward which increases the risk of going bust. I would like to know if it is really necessary to combine two expansion cases with an induced displacement in a scalar method.

Regards