Multi-Degree-of-Freedom Hybrid Fire Testing in a Non-Linear Environment

Hybrid Fire Testing (HFT) is a performance-based approach for structures in fire based on substructuring method. A complete structure is divided in two substructures, one being in a fire test laboratory (physical substructure [PS]), and one being numerically simulated (numerical substructure [NS]). By reducing the number of elements to be tested, this method overcome the huge costs of large-scale tests. Some hybrid fire tests have been successfully performed in the last decades, showing that this technique is promising. However, as HFT is still in its infancy, these hybrid tests were limited to one-degree-of-freedom (DOF) tests. In parallel with the tests, the stability of the HFT process has been studied and algorithms have been developed. These algorithms have been validated numerically but few have been used in experimental tests.
This research aims first to propose a new framework based on linear control system theory and proportional integral controller to address identified stability issues and control the time properties in HFT. The final objective consists in performing multi-DOF tests based on this methodology.