Dr. Jean-Baptiste Charrié

Due to the increase in anthropogenic and natural risks affecting civil engineering
structures, progressive collapse analysis is of growing interest. In particular,
academic research emphasize the importance of studying the influence of dynamic
effects and forces redistribution within a structure after a localized loss of bearing
capacity. In an effort to optimize experimental resources, the pseudo-dynamic
method is hereby adapted to investigate progressive collapse. A physical subassembly,
subjected to local loss of bearing capacity, is tested quasi-statically.
Inertial and viscous contributions are numerically calculated, in order to iteratively
reconstruct its dynamic response. The sub-structuring technique enables to couple
the sub-assembly with a larger virtual structure, modeled using nonlinear multi-fiber
finite elements. The method is applied to full-scale (1:1) reinforced concrete beams
integrated in a 2D numerical frame. A new implicit–explicit coupling scheme is also
developed to ensure convergence of the virtual structure without compromising the
experimental measurements. The presented results highlight the relevance of the
method, with the observation of dynamic phenomena and the propagation of
damage throughout the entire structure.