I define a positive temperture nonlinear profile and a negative temperture nonlinear profile on the same beam as follows, the absolute values of positive and negative temperature profile are the same:

LC | NO | TYPE | TITL | ||||

9 | TG | Positive | |||||

LET#T_C | +12.5 | +3.35 | 0 | ||||

LET#Z_C | 0 | 0.1[m] | 0.4[m] | ||||

LOOP#i | T_C | ||||||

BEAM | FROM | TO | TYPE | EZA | PA | REFT | |

‘GRP’ | 21 | T | #Z_C(#i) | #T_C(#i) | -Z | ||

‘GRP’ | 22 | T | #Z_C(#i) | #T_C(#i) | -Z | ||

‘GRP’ | 23 | T | #Z_C(#i) | #T_C(#i) | -Z | ||

ENDLOOP |

LC | NO | TYPE | TITL | ||||

9 | TG | Negative | |||||

LET#T_C | -12.5 | -3.35 | 0 | ||||

LET#Z_C | 0 | 0.1[m] | 0.4[m] | ||||

LOOP#i | T_C | ||||||

BEAM | FROM | TO | TYPE | EZA | PA | REFT | |

‘GRP’ | 21 | T | #Z_C(#i) | #T_C(#i) | -Z | ||

‘GRP’ | 22 | T | #Z_C(#i) | #T_C(#i) | -Z | ||

‘GRP’ | 23 | T | #Z_C(#i) | #T_C(#i) | -Z | ||

ENDLOOP |

This is the moment of positive temperature

This is the moment of negative temperature

I expect that the internal forces due to negative temperature are the opposite to those due to positive temperature, but the result are not as I expected.

I also did the analysis using **LUSAS**, the moment of negative temperature are the opposite to those due to positive temperature as shown below (LUSAS use N and m, so 436.4E3 on the beam means 436.4E3 N*m, which is equal to 436 KN*m in Sofistik)