Multi-degree-of-freedom Hybrid Fire Testing of a Column in a Non-linear Environment

Hybrid fire testing is a testing method for structures on fire based on a substructuring method. A complete structure is divided in two substructures, one in a fire test laboratory (physical substructure), and one numerically simulated (numerical substructure). In fire engineering, some hybrid fire tests have been successfully performed in the last decades, but as the method is still in its infancy, these hybrid tests were limited to one-degree-of-freedom tests. The paper presents the first successful multi-degree-of-freedom hybrid test performed in fire engineering. The physical substructure is a steel column with an axial displacement and rotations at the ends controlled by electric jacks. The numerical substructure is a non-linear 2D plane frame structure modelled in SAFIR®. The equations of the algorithm, the experimental setup, the testing process, and the results are presented.