Fire Scenario for a Composite Frame

The example below was taken from Upmeyer, Dissertation Universität Hannover 2001 and is based on a fire test conducted in Brauschweig in 1995.

Composite frame with dimensions, load and sections
Composite frame with dimensions, load and sections

The fire stress occurs according to the standard temperature-time curve. Flame is applied to the frame member from the bottom and to the frame strut from all sides.

Temperature profiles of the used sections at time t=90 min
Temperature profiles of the used sections at time t=90 min

Geometric and physical nonlinearities are included in the time-step calculation process. At the end of the calculation, the time-dependent deformations, internal forces and support reactions are available.

The time displacement curve depicted below matches the test results very well. Even the calculated failure time of 149 min differs only slightly from the test result (150 min).

Superelevated deformation figure of the frame shortly before failure (t=148 min)
Superelevated deformation figure of the frame shortly before failure (t=148 min)
Time-displacement curve uz in the horizontal frame member (location 1)
Time-displacement curve uz in the horizontal frame member (location 1)
Time-displacement curve ux in the frame strut (location 2)
Time-displacement curve ux in the frame strut (location 2)