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 Nm, which is equal to 436 KNm in Sofistik)
