Review article

Using the example of a spatial rod system calculated in the LIRA-CAD PC, a comparative analysis of the stress-strain state for stationary and cyclic temperature effects is carried out. It has been established that the variable temperature regime leads to a significant redistribution of internal forces and deformations. In the most unfavorable cases, there is an increase in deflections and longitudinal forces in the columns by more than two times compared with stationary mode. It is shown that it is necessary to take into account the unsteadiness of the temperature effect in order to reliably assess the stability of the frames to progressive collapse.