PhD candidate: Adrien Corman
Funding : FRIA
Duration: 5 years (starting: September 2017)
Joints as key elements against the collapse of steel and composite structures under exceptional loadings.
The European norms for structural design provide rules which allow ensuring an appropriate resistance and an adequate serviceability performance to civil engineering structures under usual loading situations. Nevertheless, failures of « well designed » structures are however observed, failures generally due to « exceptional » loading conditions.
In order to limit the occurrence of such failures, modern design norms require from the civil engineer to ensure an « appropriate » robustness to any structure, but no practical application rules to achieve it are provided.
In steel and steel-concrete composite construction, this request for robustness mainly focuses on the joints between structural members, these joints generally being the « weak » elements of a structure. To meet this request, it is recommended to provide an appropriate capacity of deformation to the joints, i.e. a ductility, that would allow them to « survive to the shock » in the case of an exceptional event.
The « component method » is nowadays recognised by the European norms as the reference tool to design steel and steel-concrete composite joints; but it has to be observed that the proposed method does not allow to characterise a joint in terms of plastic ductility under large deformations.
The main objective of the thesis is to contribute to the extension of the component method to this field of large deformations and to propose an analytical approach, scientifically based, to predict the deformation capacity of structural joints.
To achieve this objective, the development of fundamental researches is required. Experimental, numerical and analytical approaches will be combined in order to master the physic of the phenomena governing the deformation capacity of joints and to propose mathematical equations in agreement with the observed phenomena.