Torsional response of multi-storey buildings : contribution to the development of the 2nd generation of Eurocode 8

This master thesis aims to provide consistent work to help the development of the second generation of the Eurocode 8 focused on the torsional response of multi-storey buildings. This master thesis is the continuation of the master thesis of Maxence Carlier. The main objective is to extend his analysis focused on single-storey buildings to multi-storey buildings. Firstly, a literature review is conducted to present the concepts related to torsion and to become familiar with the Eurocode 8. Then the two conditions for the classification of torsionally flexible buildings are analysed. A comparison between the two procedures to compute the torsional radius, the 3D procedure and the simplified method, can be found in this master thesis. As expected, the simplified method is more conservative since it does not consider the horizontal structural elements. A discussion about the reference point of the torsional radius is detailed in this work as well. According to the literature and the results obtained from the numerical analysis, it would be preferred to compute it with respect to the centre of mass. Finally, a linear analysis is performed to analyse the effects of the classification as torsionally flexible on the design of a building. The impacts of the accidental eccentricity are also reviewed. Several numerical models were created and analysed with the software Scia Engineer to achieve these goals.