I have the following load cases:
L1: W+T1+P1 (OPE)
L2: W+T1+P1+D1 (OPE)
L3: W+T2+P1 (OPE)
L4: W+T2+P1+D1 (OPE)
L5: W+P1 (SUS)
L6: W+D1
L7: W

Where T1 = -10 degr C, T2 = 30 degr C and ambient temp = 15 degr C.
D1 is a tank settlement of 150mm.

Now I have used the following combinations to get my expansion stress range (all combinations are combined using the ABS method):
L8: L3 - L1 (EXP)
L9: L4 - L2 (EXP)
L10: L6-L7 (to get the streses resulting from the tank settlement.

L11 = L8 + L10 (EXP) combined using ABS method, to get the total stress range of both temperature and tank displacement.

Is this correct? Am I using the correct combinations and the correct combination method (ABS)? Thanks in advance for your replies.