Developement of a plastic theory of wood shear walls and diaphragms

• Applicant: Professor Dr.-Ing. Martin H. Kessel
• Subject Area: Structural Engineering, Building Informatics and Construction Operation
• Term: from 2006 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5438814

In the first research phase, an analytical calculation method was developed on the basis of the deformation procedure that allows loads acting on wood panel systems to be calculated on the proviso that both the ribs and the panel boarding are rigid. Comparative FE calculations revealed, however, that the load conditions for the ribs, the connection system and the boarding cannot be correctly described in all cases when the ribs are assumed to be rigid.This analytical procedure was extended to the "plastic connection method" in the second research phase, in which hinges were additionally used in the continuous rigid ribs to be able to better assess the stiffness conditions. With these changes the procedure can generally be applied to any problem in wood panel construction. The extended procedure has special significance, for instance, for ceiling panels with free panel edges that are installed in residential buildings. The modified procedure has been verified with FE simulations.The second research phase also focused on the development of the physically non-linear beam connection model for wood panels, which allows the stiffness of the ribs, the type of rib interconnection, the rib support conditions, and the type of load application to be taken into account. The emphasis was on the calculation of the loads acting on the ribs and the connection system, without considering deformations.The third research phase now is to primarily concentrate on the deformation behaviour of structures consisting of wood diaphragms and shear walls, using the beam connection model for wood panels in experimental and numerical analyses, which allows the plastic limit state to be calculated iteratively.

• DFG Programme: Research Grants